 How to Diagnose & Fix Loss of Heat on Oil or Gas Fired Hot Water Heating Boiler Systems
|
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
Heating boiler problem diagnosis and repair guide - no heat or loss of heat calls: Here we explain how to recognize & diagnose no-heat problems with residential heating boilers, including loss of heat, heating boiler noises, leaks, odors, or smoke, and high heating costs. This article explains the diagnosis and correction of no heat conditions for water or hydronic or hot water or radiator or baseboard hot water
heating systems. This website answers questions about all types of heating systems, advising on troubleshooting, inspection, diagnosis, and repairs.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
How to To Diagnose a "no heat" call: the Homeowner or Heating System Inspector Must Know the Equipment
We describe how to inspect, troubleshoot and repair heating and air conditioning systems to inform home owners, buyers, and home inspectors of common heating system defects.
The articles at this website describe how to recognize common heating system operating or safety defects, and how to save money on home heating costs.
If you don't know whether your heat is provided by a furnace (hot air) or boiler (hot water), or whether your fuel is oil, gas, or electric,
and whether your heat is hot water, steam, or warm air, see HEATING SYSTEM TYPES.
If your heat is produced by a warm air furnace and you have no heat, instead of the article found here you should see HEATING LOSS DIAGNOSIS-FURNACES.
Hot Water Heating System: Once you confirm that your heat is made by hot water (a heating boiler) you might want to review hot water or "hydronic" heating systems at BOILER COMPONENTS & PARTS and BOILER OPERATION DETAILS where we
describe the parts and operating sequence of hot water heating systems.
Note: some hybrid or mixed heating systems combine both hot water and hot air to heat a building, such as
water to air systems which use a heating boiler (oil, gas, or electric) to heat water which circulates through (and inside of) a heat exchanger
(that looks like a car radiator) - described at HEATING SYSTEM TYPES.
Types of Defects and Problems with Hot Water Heating Boilers - Hydronic Heating Systems, Loss of Heat, Noises, Leaks
What sort of defects should you look for when inspecting a heating system?
- Loss of heat in your building? - boiler or furnace won't operate, or system operates but heat is not produced in the living area - we outline a step by step diagnostic procedure for "no heat" conditions just below.
- Improper Heating System Function: noises, odors, soot, unreliability, inadequate heat distribution
- Unsafe conditions on the heating system
- Missing Heating System Components: safety controls, operating aids
- Unreliable heating systems or heating systems at or near the end of their useful life
- Improper Heating System Construction/Installation
- Heating System Damage: leaks, mechanical damage
- Clues of potential other heating system defects: leaks, corrosion, stains, abnormal temperature or pressure, high heating fuel bills
- No domestic hot water for washing and bathing? This is not usually a home heating system problem, but if your hot water is made by a tankless coil and a gas or oil fired heating boiler, the problem could be with the heating boiler itself. If your water heater is not working, find your water heater type at WATER HEATERS.
How to Diagnose Loss of Heat With Oil-Fired or Gas-Fired Hot Water or Warm Air Heating Systems
If the heating boiler oil burner is not turning on at all check the causes listed on this page. We'll take you through photo-illustrated step by step things to do when you have no heat and you need to determine what's wrong. First let's review these simple "no heat" concepts .
NO HEAT: BURNER OFF, SAFETY NOT TRIPPED: - Oil or gas burner has stopped, no safety switch is tripped
1. Is the thermostat calling for heat? check that the room thermostat setting is at least 5 degrees above the actual room temperature. See THERMOSTATS.
2. No electrical power: check that all of the switches that power on the oil or gas burner are in the "on" position. Check heating circuit fuses & circuit breakers, not just the wall switch. We discuss this in detail just below.
3. Is there fuel in the oil tank or LP gas tank? Check your oil tank or LP gas tank tank gauge.
Out of heating oil? If the marker in your oil tank gauge reads 1/8 full or less, or is at the bottom or out of sight you are probably out of oil. If your oil tank is buried, and if you do not have an indoor (remote) fuel level gauge, the oil level is checked in the tank by removing the tank filler pipe cap and using a long (clean) stick (or in emergency a clean string and weight) to measure the depth of heating oil in the tank.
Remember that a problem with the oil piping, oil filter, or fuel unit can also cause no oil to be delivered to the oil burner even if plenty of oil is in the tank. See OIL BURNER FUEL UNIT for some helpful diagnostics & also OIL & GAS PIPING.
Out of LP liquid propane gas? Check the gauge on your propane tank. If the reading is 10% or less you are out of fuel.
4. Electric motor problem at the burner or blower fan: Check that an electric motor (for the oil burner, gas burner, or blower assembly) reset switch may have tripped. See our notes above about electric motors, and see RESET SWITCH - ELECTRIC MOTOR.
5. Aquastat or cad cell control or relay trouble: if you hear or have ever heard buzzing from any heating system control that includes a relay switch, watch out for a control cover that is in contact with a relay switch in the unit. If the cover is lightly touching the relay switch the control may simply buzz when the relay is trying to move. But a too-tight control cover can also prevent a relay from operating, leading to loss of heat. Simply pulling off the cover to let the relay move freely can immediately discover and "fix" this problem. Details and illustrations are at HEATING SYSTEM NOISES.
NO HEAT: BURNER HAS TURNED OFF ON SAFETY: Oil or gas burner has stopped, the safety switch is "off" or "tripped"
If you are not sure how to find and check the safety control reset buttons on your heating system, we describe these controls in more detail just a bit further on in this article.
The burner on your heating boiler, furnace, or water heater has shut down, if a red "reset button" has popped up on the burner primary control or on an electric motor that operates the system. This condition is called "Safety Off".
Watch out: Before re-setting the safety switch or button, it's a good idea check the following five common causes of loss of heat leading to a Safety Off condition. Photos and details follow these short paragraphs.
How to press the heating system reset button: If you do not see anything wrong, you can try re-setting the heating system: press and hold the red reset button down for 3 seconds and release it. If the heating system has electricity it will try to re-start.
Watch out: If the system does not keep running smoothly don't keep pressing the reset button - that could flood the combustion chamber with unburned fuel, causing a dangerous puff-back. Just press the reset button once. If the heating system starts and runs ok, you still should request a service call, but you can have heat while you're waiting.
1. Heating fuel failures - out of oil in the oil tank, clogged oil filter, clogged oil nozzle, oil line has been bent, crimped, clogged, clogged oil pump strainer (fuel unit strainer), or inability of the fuel unit to pump oil (broken motor shaft, missing internal bypass plug on a two line oil tank system, an air leak in the oil inlet line, or a leaky foot valve in the oil tank causing loss of oil prime). if the oil tank is outdoors in freezing weather the oil in the tank or in an oil line may have become waxy or jelled.
2. Oil burner motor failure: the electric motor that runs the oil burner may itself have gone off on reset. Some causes of electric motor failure: one pipe oil system with the bypass plug installed in the fuel unit (oil pump) causing excessive pressure and stalling the motor; centrifugal motor switch sticking (try banging on the motor once); motor condenser burned out; motor stator or internal windings burned or shorted; motor bearing failure. Try re-starting the motor - see RESET SWITCH - ELECTRIC MOTOR
3. Oil burner ignition failure: the oil burner's ignition transformer terminals are loose; the electrodes on the burner nozzle are dirty or not set to the proper gap; the oil is contaminated and is hard to ignite; the ignition transformer has become weak or has burned out (look for tar oozing out of the ignition transformer container); the oil burner nozzle is clogged preventing oil from contacting the ignition spark arc; the ignition electrode(s) are grounded on the air tube of the burner;
4. Faulty heating system control operation: the safety sensor that checks that a good oil burner flame has been established is not working; a stack relay spring or cad cell eye may be dirty with soot; the stack temperature may be too low for the stack relay (boiler is under-fired); the oil burner has been cycling on and off to frequently (a problem with the thermostat).
5. Irregular stack temperatures: in the flue can cause oil burner draft and temperature or control problems. Downdrafts (missing chimney cap), insufficient draft due to chimney problems, or fluctuating oil burner flame may be at fault. Also see CHIMNEY INSPECTION DIAGNOSIS REPAIR.
-- some of this material is paraphrased from Audel.
Oil Burner Operating Problems: Oil or Gas Burner rough, noisy, smoky, smelly
The heating burner operates but not properly. See OIL BURNER NOISE SMOKE ODORS
Next let's check each cause of no heat in detail; if your system uses warm air heat instead of water or steam, review the check-items just below before going to HEATING LOSS DIAGNOSIS-FURNACES.
SAFETY WARNING: If a heating system oil burner has been deliberately "shut down" and you don't know when or by whom this step was taken, beware of turning the heating system back on without an inspection and safety check by an expert technician.
- Electrical power to the heating boiler or oil burner is OFF: check the circuit breaker or fuse supplying power to the unit; check the service switch at the furnace or air handler, and if the system is air conditioning or a heat pump, check the service switch outside at the compressor/condenser unit to be sure it is "on".
Make sure that electrical power is on for all of the heating system components. Check local
switches at the boiler, wall mounted boiler
switches at the stairwell down to the basement or utility room or in other areas, and check
the circuit breakers or fuses in the electrical panel.
Is the heating boiler turned on? Is there electric power to all of the heating system components such as an oil burner at the boiler and power to the circulator pumps? |
- Oil Burner safety reset switch is OFF or TRIPPED: the heating or air conditioning system may have been turned off on reset - see our "off on reset" and other advice at CAD CELL RELAY SWITCH (modern equipment).
LP and natural gas fired heating equipment and water heaters also have safety controls including temperature limit controls and gas spillage sensors (see list of reset switches below).
For gas heat, turn off electrical power to the gas fired heater using the service switch. Wait two minutes and turn the electricity back on. See ELECTRICAL POWER SWITCH FOR HEAT. This will reset most gas heating equipment.
For oil heat: are you sure there is no safety or reset button tripped?
Where are all the heating system reset buttons? If you are looking for the main reset button on heating equipment you'll want to see: AQUASTAT CONTROL Functions and CAD CELL RELAY SWITCH (hot water boilers and some water heaters), Stack Relay Switch on older oil fired boilers and furnaces, SPILL SWITCHES (gas fired equipment), and also Low Water Cutoff Controls on steam heating systems. At ELECTRIC MOTOR OVERLOAD RESET SWITCH we discuss the thermal overload switch and reset button that is found on many electric motors including those operating air conditioning fans, heating system oil burners, and furnace blowers and motors.
A Stack relay switch may be installed on the flue vent connector and may be in the "safety - off" position. To identify and reset this control see Stack Relay Switch. Stack relays are found on older oil fired furnaces and boilers. |
- Check the heating fuel supply again: if it is a gas furnace, is the gas turned on? If your gas is from bottled or LP gas, is the tank empty? If it is an oil fired heating furnace, check the gauge on the oil tank. Are you out of oil? See OIL TANK GAUGES.
If you're out of oil or gas call your oil or gas company and request an emergency delivery. For oil systems, usually the delivery person will also need to enter the building to bleed air
from the oil lines in order to get the oil burner operating again. For gas fired heating equipment the driver may want all gas appliances turned off in the building during delivery.
Still no heat? Once you have assured that you have heating fuel and that electrical power is turned on to the heating unit, if you still don't have heat check these controls:
- Thermostat is in the "off" position or is set to a temperature that does not call for heating (or cooling) See FAN AUTO ON Thermostat Switch for details about what turns the blower fan on and off.
- Flue gas spill switch: If your heating boiler is gas-fired (natural gas or "bottled" LP gas), a flue gas spillage switch may have shut the system down after sensing possibly dangerous flue gases (that can contain fatal carbon monoxide). See Spill Switches. This switch will not normally be found on oil fired heating equipment.
- Is there fuel for the boiler ?: check the oil tank gauge (see OIL TANK GAUGES for tips on how to find, read,and test the oil tank gauge. If the heating boiler is fired by natural or LP gas and not oil, check that no one has
shut the gas supply valves.
Oil burner motor coupling: another cause of an oil burner starting to run but never igniting at all may be a broken or slipping coupling (or a frozen coupling) between the oil burner motor and the fuel unit. In this case the burner starts in response to a call for heat, but there will be no ignition whatsoever because no oil is being delivered to the nozzle assembly.
Other reasons for no oil flow to the oil burner include: an oil safety valve that has been "closed" (someone turned it the wrong way), low oil or no oil in the heating oil tank (the tank may not be completely empty but oil may be below the oil pickup line if the oil lines are exiting at the top of the tank), a clogged oil filter or fuel unit strainer, a clogged oil burner nozzle, a air leak in the heating oil supply piping, or a crimp or clog or restriction in the oil piping. If you recently ran out of oil and then got a delivery, and if your system uses a single oil line between tank and burner, the line or fuel unit may be air bound and needs to be bled. [8]
- Is the thermostat calling for heat? and is the temperature at the thermostat lower than the thermostat setting?
- Does the oil burner start but then shut off? Is the system "off on reset"? if so the red "reset" button will have popped up on the oil burner
control (or possibly on an electric motor operating the oil burner) and the system has an operating problem and needs service. It may be possible to re-start
an oil burner that has turned itself off by pressing the red reset button ONCE.
If the heating boiler or furnace re-starts and runs acceptably, you can have heat while
waiting for the service technician but the system still needs inspection, service, and possibly other repairs before it can operate safely and reliably.
If you push the reset button and the burner does not start and keep running for five minutes or more, DO NOT try again as you may flood the system
with oil and make restarting difficult and dangerous.
- Is the oil burner motor off on reset? See MOTOR OVERLOAD RESET SWITCH
- Boilers-Hydronic Heat: Is hot water water circulating?
- Check the hot water circulator: Test to see if the circulator is operating Feeling the hot water distribution piping (Watch out it should be HOT!). Feeling the piping can indicate if circulator is running or not -- a quick change in temperature means the circulator works; slow change in temperature may occur if the circulator does not work but hot water is circulating by convection.
- Check for a bad zone valve or bad circulator pump relay. If the building has more than one heating zone it probably uses either multiple circulator pumps, each of which is operated by a circulator relay switch that is in turn operated by a wall thermostat, or it uses multiple zone valves, each of which is operated by a thermostat. A bad circulator motor or pump, a bad circulator relay (or even a circulator relay cover that is pressed against and jamming the relay switch), or a stuck zone valve (common on some models) will prevent heating water from circulating in that zone while other zones may work fine.
- Check hot water baseboards: if some baseboards are hot and others cold, are they all on the same heating zone? If not, are all of the thermostats turned up? If some heating baseboards are hot and others cold
and we're sure that they're on the same zone, then the system is probably air-blocked. A heating circulator pump is capable of pushing water around in the
loop of heating baseboard but is often not capable of overcoming a section of baseboard that contains a large bubble of air.
It's necessary to remove such
air blocks. If air blocking has been recurrent a previous owner may have installed air bleeders at strategic points. The bleeder can be opened slightly
and carefully, to permit air to escape. As soon as water starts coming out of an air bleeder valve it can be closed. Automatic air purge devices are available
and are usually installed right at the heating boiler but sometimes additional ones are needed at higher levels in the building.
- Check hot water radiators or convectors: if some radiators or wall convectors are hot and others are cold, and provided that the individual
feed valves located at each of these devices is open (turned counterclockwise) the radiator or convector may be air blocked. Usually an individual air
bleed valve is located on each of these devices.
- Check the Oil Heating Equipment Safety Controls and Switches - see FIRE SAFETY CONTROLS for photos and details
- On gas fired heaters check for flue gas spillage at the heater or for a bad flue gas spillage switch: If your furnace is gas-fired, a flue gas spillage switch may have shut the system down after sensing possibly dangerous flue gases (that can contain fatal carbon monoxide).
See Spill Switches for details.
- On oil fired boilers or furnaces check for a bad automatic draft damper switch. If the draft damper does not open in response to a thermostat's call for heat the heating appliance will not start.
How to Diagnose Soot or Noises during Heating System & Oil Burner Operation
For full details of this topic be sure to see OIL BURNER NOISE SMOKE ODORS.
- Noises during oil burner startup - a "bang" or puffback which blows soot into the room through the barometric damper or through other equipment openings: the oil pump may not be shutting down properly at the end of
an oil burn cycle, leaking incompletely burned oil into the combustion chamber. That oil ignites at startup causing a potentially dangerous puffback. Immediate service and repair are needed.
- Soot and black marks in the living area can sometimes indicate an unsafe or poorly-functioning heating system but these marks can also be normal in some buildings depending on other conditions. Details about soot tracking are at THERMAL TRACKING.
Watch out: Safety warning about soot: Sooting can occur with both gas fired and oil fired systems. Soot coming from a gas fired heater is probably indicating a very dangerous condition risking carbon monoxide poisoning. If a gas fired appliance is producing soot, it should be turned off and Immediate service is needed. See COMBUSTION AIR DEFECTS and also SOOT on OIL FIRED HEATING EQUIPMENT and GAS FIRED WATER HEATERS for safety warnings about soot at heating appliances.
- Noises during oil burner startup - a "rumbling" sound (which usually continues all during operation" or a "stumbling" sound in the combustion chamber probably indicates that the system needs inspection and cleaning very soon. Some noise is normal however, but the normal sounds tend to be more smooth and continuous.
- Noises during oil burner shut-down - a stumbling or rumbling after the oil burner motor has stopped, indicate that oil is continuing to leak into the combustion chamber and risks a dangerous puffback - see "Noises during oil burner startup" above. Immediate service is recommended.
- Noises of shrieks or grinding coming from the electric motor or oil pump on the oil burner mean that immediate service is needed - probably a bearing is failing.
- Startup problems: noises and clues of puff back: if you see flapping at the barometric damper or if you see or hear vibrations in the system, or if you see black soot on or near heating equipment the system may be unsafe and prompt service is needed
- Noises from radiators or heating baseboards: clanking pipes or sharp snapping noises may be heard as a normal consequence of expansion of metals during the heating cycle. These noises can often be eliminated or reduced
by careful routing of piping and by allowing room around heating pipes for expansion, but probably not eliminated in the case of hot water baseboards.
Bubbling or rumbling noises in hot water heating piping can be caused by air in the heating lines. If the amount of air becomes excessive the
system may be unable to circulate hot water and extra steps to bleed unwanted air will be required.
Hissing sounds such as air escaping from
radiators or other piping where air bleeder valves are installed are normal but should be brief and uncommon. If you constantly hear air
hissing from radiator bleed valves double check that you understand what kind of heat you have - hissing from bleeder valves on steam
heat radiators as heat is coming up in the building is normal.
How to Evaluate Heating Boiler Leaks & Corrosion
For full details of this topic be sure to see BOILER LEAKS CORROSION STAINS.
When observing evidence of leaks on a heating boiler, keep these points in mind:
- Even serious leaks may never show up as "wet" spots: A boiler may be leaking but you may see no actual water: during the heating season the boiler may always be hot, causing small leaks on the boiler or on heating piping to simply evaporate. But such leaks will usually be visually very evident: look for a build-up of corrosion, green or white or other colored mineral salts, or look for rust or water stains on the equipment.
- Internal heating boiler leaks: Some critical boiler leaks may be internal and not visible by simple inspection, such as a leak inside the boiler heat exchanger which may pass water into the combustion chamber. A service technician or a skilled home inspector should be able to spot evidence of these leaks.
- Surface rust, light, superficial rusting, is generally repairable. Clean the area and fix the leak when the boiler is next serviced and monitor for any future leaks.
- Exfoliation, or thick flaking rust on any boiler but particularly on a steel heating boiler is very serious, possibly not repairable, and risks loss of the boiler as well as sudden loss of heat in the building. Examples of this problem are at TANKLESS COILS
- Leaks related to temperature or pressure: Some leaks occur only at peak operating temperature-e-g at relief valve. On some heating boilers such as some cast-iron units, leaks may occur between boiler sections when the system is cold - on these models some technicians prefer to keep a little heat in the boiler year-round to avoid this problem. Leaks between boiler sections may be repairable but if left unattended can destroy the equipment.
A Catalog of Common Heating System Leak Points - Where to Watch for Heating System Leaks
- Tankless Coil mounting plate - see rust stains below and around plate - see TANKLESS COILS
- Pipe fittings anywhere in the system, including in water supply piping to a boiler, hot water distribution piping, or at face of coil plate - mineral salts and stains may show even a small leak though no water may be visible (it evaporates quickly on hot heating system components)
- Leaks around bolt openings - suspect hidden damage
- Leaks between sections of a cast iron boiler
- Leaks at the circulating pump mounting flanges
- Leaks at the boiler temperature/pressure relief valve. This leak may be very dangerous as corrosion from water passing through the valve may prevent its safe operation in an emergency. Prompt expert inspection and repair are needed. Watch for leaks below the valve's mouth or discharge pipe (a pipe should extend from the relief valve to a few inches from the floor) or watch for corrosion at the tip of the discharge pipe. Gently feel inside the tip of this pipe to see if it's wet. DO NOT TRY TO TEST or open or operate the relief valve itself.
Safety warning: a leaky relief valve indicates an potentially very dangerous condition; prompt service is needed.
- Leaks at air bleeder valves - at the boiler or remote where such bleeders are placed on heating piping or baseboards or radiators
- Leaks at radiator control valves or between radiator sections
- Leaks at heating baseboards, at poorly-soldered copper pipe fittings on finned copper baseboard heating systems
- Leaks due to frozen and burst piping or in extreme cases, frozen and burst heating boilers themselves. Freezing pipes produce very distinctive types of damage such as splits or separation at solder joints.
How to Recognize & Diagnose Inadequate Combustion Air for Oil-Fired Heating Systems
For full details of this topic, also see Inadequate Combustion Air
Lack of adequate combustion air can result in improper system operation, sooting, increased heating cost, damage to oil burner components (back pressure heat can destroy an ignition transformer), higher and more frequent heating service costs, loss of heat, noises, smoke, and potentially, the production of carbon monoxide or other flue or combustion gases which escape into the building - potentially dangerous
Safety warning: The sketch shown here, courtesy of Carson Dunlop, explains how dangerous furnace back-drafting can occur when there is insufficient combustion air. These conditions can not only release flue gases into the occupied space, but they are likely to cause the production of potentially fatal carbon monoxide.
We've seen heating equipment that seemed to work just fine during its adjustment because the service technician was working with the door to the furnace or boiler room open. But when she left the system and closed the furnace room door, suddenly there was insufficient combustion air.
Also see
Unsafe Air Conditioning or Heating Duct Openings which describes the risks of
reduced combustion air on hot air heating systems when certain return air duct defects are present, and also see
CARBON MONOXIDE - CO and CHIMNEY INSPECTION DIAGNOSIS REPAIR
A Guide to Heating Equipment Malfunctions & Their Implications
- Noises & soot buildup can lead to a potentially dangerous puffback which can damage the heating equipment and blow soot and smoke throughout the building.
- Leaks on hot water heating systems are never acceptable, anywhere. Leaking relief valves need immediate attention and repair (Leaking relief valve could be due to water-logged expansion tank, improper control settings (temperature too high), improper automatic water feeder operation (pressure too high), or defective valve (leaky). True, you only have to report the valve. Did you miss problems at the other components?) Corroded relief valves also need to be test by a service technician and repaired or replaced
- Relief Valves: Do not touch the heating boiler or water heater temperature or pressure relief valve - it may open and fail to shut down. A relief valve which does not work is dangerous since the system is missing an important safety device. Should an over pressure or over temperature condition develop for other reasons, the boiler could explode.
- Corrosion on heating system parts: Do not pick at corrosion as you may start a catastrophic, un-stoppable leak requiring total system shut-down. Leaks left un repaired can destroy heating equipment.
- Tankless coils for making hot water: If there is different water pressure/flow observed in the kitchen in which the hot water pressure is significantly less than cold, even before examining the building's mechanical systems you may speculate that a tankless coil installed may be installed. What other clues suggest that the local water supply may be hard in minerals and that there may be a risk of clogged piping? When the water supply is high in minerals, the hot water pipes or tankless coils clog up before cold water piping. Is a water softener installed? Is there known "hard" water--have mineral deposits clogged the coil? Are there "cleanout" plumbing fittings on the tankless coil piping? Does this suggest a history of clogging and acid-flush treatments? A clogged coil can be repaired or replaced. How severe was that rust you observed at the tankless coil mounting plate? Severe rust may mean that the boiler must be replaced.
Examples of Heating System Defects with Important Implications
- Lack of adequate combustion air can result in improper system operation, sooting, loss of heat, noises, smoke, and potentially, the production of carbon monoxide or other flue or combustion gases which escape into the building - potentially dangerous
- Leaky oil at an oil burner ignition transformer: watch for back pressure in combustion chamber--watch out for blocked heating flue or blocked chimney - these would be unsafe, or the heater may be unreliable. An unreliable heater can lead to
frozen burst pipes and costly building damage. A blocked chimney could lead to a potentially fatal carbon monoxide hazard.
- Unusual interior moisture conditions, noises, smoke, or odors during heating season--watch for blocked chimney or poor flue vent connections
- Equipment recalls: Specific heating system problem brands Repco, Blueray etc.
[Do not confuse Repco™ heating boilers, which had fire chamber and other failures, with other products (REPCO pumps, REPCO controls, REPCO water conditioners, or water treatment that carry the Repco name. Those products are distinct from REPCO heating boilers and are produced/distributed by the R.E. Prescott Company. Further, we are unaware of any remaining warranty or replacement support for failed or antiquated Repco heating boilers.]
- Blueray Heating Boilers/Furnaces Safety Recall by the US CPSC, with additional history, photos, and technical details; Blue Flame Blue Ray
- Carbon Monoxide Gas Toxicity, exposure limits, building inspection for CO hazards
- Fuel Oil & Oil Heating Magazine, 3621 Hill Rd., Parsippany, NJ 07054, 973-331-9545
- Goodman Furnace High Temperature Plastic Vent HTPV safety recall US CPSC notice
- Home Heating System Should Be Checked [for proper venting and for CO Carbon Monoxide Hazards - DJF]
- Inspection Procedures for Oil-Fired Heating Systems Detailed step by step approaches for inspecting complex systems]
- Lennox Pulse Furnace Safety Inspection/Warranty Program: Carbon Monoxide Warning
- Oil Tanks - The Oil Storage Tank Information Website: Buried or Above Ground Oil Tank Inspection, Testing, Cleanup, Abandonment of Oil Tanks
- Oil Tanks Above Ground, UL Standards, guidance for home owners, buyers, and inspectors
- Home Inspection Report Language Library: Gas Fuel Piping or Tank Faults Basic advice - home inspection report language suggestions
- Home Inspection Report Language Library: Buried Oil Tanks, Basic home buyer advice - home inspection report language suggestions
- Home Inspection Report Language Library: Defects in Oil Tank Installations, Tanks, and Heating Oil Piping
- Plastic Heating Vent Pipe & Other Heating Safety Recall Notices
- Weil McLain Model GV Gas Boiler/gas valve CPSC recall/repair
Frequently Asked Questions (FAQs) about how to diagnose & fix hot water heating boilers & systems
Question: our heating boiler won't heat our hot water
Hi. our problem is that while our central heating is fine,our oil boiler will not heat our hot water. A local plumber has replaced all relevent parts,apparently, but still no hot water until the water has been running from the tap for around 25 minutes. - KennyBrown999@hotmail.co.uk - 9/9/2011
Reply:
Kenny: sorry I couldn't even guess at what's wrong with so little information. "all relevant parts" - may not have really been "ALL" since you still have the problem. How is your hot water made - by tankless coil? If so the coil may be blocked with mineral deposits.
Question: oil fired heat not working
My oil heating is not working. the thermometer symbol is lit up on the boiler - Margaret 10.21.11
Reply:
Margaret, it sounds as if a diagnostic light is lit on the primary control of your heater - it's time to call a service technician. Unfortunately hou didn't give me any other info; though you might get some help by following the basics at the top of this article - making sure you have electrical power & fuel and that the thermostat is calling for heat.
Question: oil burner won't fire-up
I have an issue with my boiler with the burners not firing. When the water temperature gets down to 180 degrees it goes into heat mode as it should. The electronic damper opens and the pilot begins to click. I am getting spark at the pilot but no flame. If I turn the gas control valve to off and wait until I hear a "puff" sound, which is the pilot actually lighting, and quickly turn it to the on position it will fire and heat the water to 200 degrees then shut off as it should. I am thinking it is an adjustment to the gas flow on the gas valve or a faulty valve but I am not sure at this point. - kwoyach@frontier.com 11/12/11
Reply:
Kwoyach, I don't have a clear understanding of your heating system but indeed, "I am getting spark at the pilot but no flame." points to a problem with the gas valve or burners. I'd call a service tech for some diagnosis before replacing the gas valve. There could be a gas pressure or regulator problem or even a problem with a safety device or CO sensor.
Question: gas fired warm air furnace - gas boiler - huh?
I have a very strange issue with my brand new boiler/heating system and I'm pulling my hair out trying to solve it. I have a Forced air, gas boiler heating system. The boiler has one pipe that feeds 3 pumps; zone 2 heating, zone 1 heating, and Hot Water. I have never had a problem with Zone 2 or Hot water but Zone 1 is another story.
Every 2-3 weeks my 1st floor heating blows cold air from the vents. The problem is fixed when I bleed Zone 1. But it keeps happening. I have replaced the copper piping that leads to the blower and I have replaced the pump. An electrician has also assured me that it is not an electrical problem. But it happnened again this past week. Any suggestions as to what might be causing this? Any help is greatly appreciated. - Jason 11/15/11
Reply:
Jason, If I've got it right you are describing a mixed hydronic and water-to-air heating system with at least one zone that uses a heating convector and air blower to deliver warm air to part of the building. If the blower fan runs but the air is cold, then your convector is not heating up. When that zone is calling for heat, feel the pipes leading to and from the convector - I'll bet they're staying cold. That suggests that a zone valve is not opening to circulate hot water to that piping loop, or the piping or convector itself have become blocked. Keep us posted - what you learn will help other readers.
Reader follow-up:
OK....so I have now replaced the check valve that sits above the circulator pump. It worked last night and then the system was off until the morning. In the morning, system was blowing cold air again. I bled the system (which normally gets heat to work) and it did NOT work. I then banged on the check valve once with my wrench and it started to work. What is going on? Brand new system. I am losing my mind. Thanks - Jason
Reply:
Jason, flying somewhat blind with so little understanding of just exactly what you've got installed, but
- why are you repeatedly bleeding the system (presumably of air) ? Either you're missing a working automatic air purge vent or there is a system leak that's admitting air into the hydronic piping or boiler, right?
- check valves or flow control valves are normally there just as an anti-siphon device to keep hot water from circulating by convection when the circulator is not running. I don't see them clogging often but if there were an unusual amount of debris in the system that could be occurring.
But usually I don't expect a double fault - that is, typically just one of the explanations is likely to be the root cause.
Feel the piping leaving the boiler and enroute where you can access it; the point at which piping is cold is the beginning of a blockage, perhaps by air or even by a piping error (a solder blob?).
For a brand new heating system, I'm surprised that you're not able to get the installer back to diagnose and repair it. Is the work not guaranteed?
Question: when I bleed the heating radiator black water comes out
when i bleed the radiator. black water is coming out. the system has only recently been installed - William Hanna 11/27/11
Reply:
William, at RADIATORS (article links listed at Related Topics or top ) you will find details about using the air bleeder valves on radiators. In general, you should be bleeding AIR out of the radiator, not water. If you open the valve and allow air to escape, as SOON as you see water coming out of the valve you should close it.
It's common for the water in a hydronic (hot water) heating system to be black and ooky looking, and in hot water systems it is most likely not a concern.
Question: why does one of our rooms get no heat?
Hi, we have a forced hot water system. I'm wondering why,if all of our rooms are in the same zone, one room cannot seem to be heated? - JL 12/26/11
Reply:
JL
about having forced hot water heat and one zone and one room not heating, it's possible that the radiators or baseboards in that room are airbound (see AIRBOUND HEAT SYSTEM REPAIRS in the article links at page top or left)
Question: heating system makes noise at startup
system starts up makes grinding noise and shuts off - Jim 12/26/11
is it easy to change bearing - Jim
Reply:
Jim,
changing a motor bearing is usually not something that's easy to do without special tools - we have to press out the old and press in the new, as well as of course disassemble the motor. It depends of course on what motor and what system you're discussing. For example I would not try to change the bearing in an oil burner fuel unit (oil pump) - I'd replace the whole unit.
About your heat shutting off, if you're hearing grinding from the driving electric motor or fuel unit, I'd replace the part and thus get heat up and running again. If the noise is traced to improper burner operation you need a service call
Question: oil fired boiler turns on but no hot water leaves the boiler - and steam is coming out of the pressure-temperature relief valve
I have a warmflow bluebird oil fire boiler, where the boiler is firing but no hot water is exiting the boiler, and there is steam coming from the overflow pipe. Does this imply a problem with the internal pump ? - Jason 5/22/12
Reply: shut off the unsafe boiler immediately and call an expert
Jason
Watch out: I would SHUT OFF THE BOILER IMMEDIATELY
and call for a service technician. If the boiler is low on water it could be damaged or worse, unsafe.
Question: boiler will start and run but no heat enters the house
I have a burnham boiler with three zone valves (garage, house, hot water). There is fuel in the tank. The boiler will start and run fine however it does not distribute any heat throughout any of the zones. It shuts off when it reaches its temperature. I have had this happen once before and it lasted for a couple days and then started working again. What could be causing this? What should I do? I live in Alaska, please help - Heather 9/28/12
Reply:
Check for a circulator that is not running or zone valves not opening.
Question: one pipe steam system not working
I have a Burnham boiler (actually two) with a single pipe steam system. We shut the gas off to the boilers during the summer and restart them each fall. The startup sequence is
1. turn on thermostat and turn temp up (they are upstairs)
2. turn on gas valve on gas line.
3. turn on safety shutoff switch on boiler.
4. turn pilot gas valve from off to pilot, depress, and light pilot. Wait for pilot to heat millivolt sender.
5. Turn pilot valve to ON.
Furnace will usually fire up. This time, the pilot will light and stay lit, but no action from the boiler. I have checked the voltage at the thermostat and it is .25 V.
Closing that circuit does not fire the boiler. There is water in the boiler. It looks like there are two pressure safety switches and the low water cutoff. How do I check them? what else should I look at?
Richard - 10/9/12
Reply:
Richard, steam heating system diagnostics are over at STEAM HEATING SYSTEMS
Question: smoke pours out when our oil fired boiler starts up
I HAVE A HOME HEAT BY A OIL SISTEM BOILER ,AND IS MAKING A LOT SMOCK WHEN IT GOES ON W. - Anon 10/28/12
Reply: shut off the boiler - beware of a puffback explosion
Anon
Watch out: If your heater smokes at startup it is not operating properly and needs cleaning and service by a professional; I suspect a bad fuel unit shutdown - you are in danger of a puffback - so don't delay.
Question: when I tap on the transformer on our Beckett oil burner it will run - else not. Can it be fixed?
I HAVE TO TAP ON BECKETT TRANSFORMER FOR IT TO COME ON DOES IT NEED REPLACED OR CAN IT BE FIXED - Dave 10/29/12
Reply:
Dave:
look for a loose wire or a defective control or transformer;
If that doesn't do the trick it's time to replace the transformer.
[People who type in all types get their text made teensy.]
Question: My heater stopped working - I like this heating company ...
"Thanks for all the help! I'm staying at my sisters house watching the kids while she's away and the heater stopped working. I wanted to check here to see if I could figure out the problem on my own before having to call an hvac service in Modesto CA Thanks again, I'm gonna go see what I can do. "
we're here to help with basic advice but indeed a homeowner should not think they can actually service their own heating system beyond the basics, as training and equipment are needed for safe operation of the system. Stacey 10/30/12
Reply:
Stacey,
RE: your message
Your message was deleted because you included a URL to a service company - a conflict with our policy.
Question: I get hot water but no heat from our heating boiler
I have a burnham hot water boiler that I get both heat and hot water from, my problem is i'm getting hot water but no heat can you tell me what to do or try. So far I've tryed bleeding the boiler and some oof the baseboards. - Anon 11/16/12
Reply:
Anon, if the heating boiler is running enough to heat the tankless coil to give you domestic hot water but no heat comes out of heating baseboards or radiators, check that the thermostat is calling for heat, that the circulator pump runs, and if there are zone valves, that they are opening.
Question: I keep draining water from my steam boiler but the water level in the glass tube never drops - what's wrong?
i have opened up the water (with a sump pump in a 5 gallon bucket) for some time, yet my glass tube never goes down? any ideas? - Damian 11/16/12
Reply:
Damian,
Watch out: I am not sure what you're up to, but most likely the automatic water feeder is just adding more water to the boiler whenever you drain some out. Thank goodness. If you drain the water out of your steam boiler and the low water cutoff does not function to shut down the system the boiler is likely to be ruined, or worse. See STEAM HEATING SYSTEMS
Question: my water heater has a damper, it's open, but the heater won't come on
i have universal water heter that one has damper on it but damper open but heter did not fire get on - Anonymous 12/5/12
Reply:
Perhaps, Anon, you are referring to an electric or power damper in the flue vent connecot of your heater. For safety, on a call for heat the damper is supposed to open (to let combustion gases flow up the chimney) but if it doesn't the heater won't turn on. Of course there could be any of a number of other reasons for no heat. Check the items suggested in the article above.
Question:
the thermostat signals but the furnace will not turn on - Tom 12/10/2012
Reply:
Tom there could be any of many reasons that you don't get heat when the thermostat calls for it. Your best bet is to start at the top of this article and run through the checklist.
...
Ask a Question or Search InspectApedia
Questions & answers or comments about how to fix a heating boiler that is not working - how to diagnose the loss of heat in a building when the heat source is an oil or gas fired boiler
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
- Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
- Home Inspection Education Courses including home study & live classes at eleven colleges & universities.
- Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program.
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference Book, a reference & inspection report product for building owners & inspectors.
Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones.
Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
- The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
- The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
- Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
- National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
- The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
- Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
- The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
- Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
- "Residential Steam Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
- "Residential Hydronic (circulating hot water) Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
- "Warm Air Heating Systems". Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
- Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
- Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
- Installation Guide for Residential Hydronic Heating Systems
- Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
- The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
- R.E. Prescott Company, a producer of other REPCO™ residential and industrial products as well as a provider of design-build engineering services is at 10 Railroad Avenue, Exeter, NH 03833. Tel: 603-722-04321 or 888-786-7482. Trish O'Keefe from Prescott informed us (10/7/2009) that their company had nothing to do with the failed Repco heating boilers discussed at InspectAPedia.com. She wrote:
- Our company manufactures & distributes residential water treatment equipment, including our Repco line of conditioners. We have a plumbing & heating supply dept as well. We are mistaken for the Repco Boiler company on a regular basis, most frequently in Oct. and Nov.
- Any information you could give me on the other Repco company would be appreciated. We've assumed it is no longer in business, and we'd like to know that for sure. Many callers want to know where to get replacement parts and I would be glad to direct them if I knew...plus there's always a chance they might be interested in a Crown Boiler instead.
- Thanks to Bottini Fuel service manager Ron Thomas for discussing aquastat functions, low limit controls, oil burner short cycling causes, and boiler maintenance, reliability, and service contracts 4/13/2010. Bottini Fuel is a residential and commercial heating oil distributor and oil heat service company in Wappingers Falls, NY and with offices in other New York locations. Bottini Fuel, 2785 W Main St,
Wappingers Falls NY, 12590-1576
(845) 297-5580 more contact information for Bottini Fuel
- [8] Suntec Model A-7400 Fuel Unit Solenoid Dumping Pump,
Suntec Industries Inc., 60 Aberdeen Drive - PO Box 5000
Glasgow, KY 42142-5000 - USA
Tel : 270 651 7116 - Fax : 270 651 9276
e-Mail : info@suntecpumps.com and
Suntec Industries France,
1 Rue Lavoisier - B.P. 102
F-21603 LONGVIC Cedex - FRANCE
Tel : +33 (0)3 80 70 60 70 - Fax : +33 (0)3 80 70 61 11
e-Mail : information@suntec.fr, [copy on file as /heating/Oil pumps fuel units/Sunted_Solenoid_DumpingPPump.pdf] ,
Also /Suntech_Solonoid_Safety_Valves.pdf (brochure)
web search 4/19/12, original source: http://www.suntecpumps.com/Suntecus/PDFs/Form%202740%20
-%20Solenoid%20Dumping%20Pump.pdf
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
 The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
|
- Carson Dunlop, Associates, Toronto, have provided us with (and we recommend) Carson Dunlop Weldon & Associates' Technical Reference Guide to manufacturer's model and serial number information for heating and cooling equipment
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
- Links to our list of additional information on heating system inspection, repair, maintenance
- ...
