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AFUE DEFINITION, RATINGS
AGE of AIR CONDITIONERS & HEAT PUMPS
AGE of HEATERS, BOILERS, FURNACES
AIR CONDITIONING & HEAT PUMP SYSTEMS
AIR FILTERS for HVAC SYSTEMS
AIR HANDLER / BLOWER UNITS
AIRBOUND HEAT SYSTEM REPAIR by WATER FEED VALVE
ANODES & DIP TUBES on WATER HEATERS
ANTIFREEZE for BOILERS
ANTI SCALD VALVES
APPLIANCE EFFICIENCY RATINGS
ASBESTOS IDENTIFICATION IN buildings
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTERS, HEAT
BACKDRAFTING HEATING EQUIPMENT
BACKUP HEAT for HEAT PUMPS
BIOGAS PRODUCTION & USE
BLOWER DOORS & AIR INFILTRATION
BLOWER FAN CONTINUOUS OPERATION
BLOWER FAN OPERATION & TESTING
BLUE vs YELLOW COMBUSTION FLAMES
BOILER PRESSURE & TEMPERATURE SETTINGS
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
BUILDING SAFETY HAZARDS GUIDE
CAPACITORS for HARD STARTING MOTORS
CARBON DIOXIDE - CO2
CARBON MONOXIDE - CO
CHEMICAL TREATMENTS for BOILERS
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CHIMNEYS & Flues - Asbestos Transite Pipe
CHINESE DRYWALL HAZARDS
CIRCULATOR PUMPS & RELAYS
COOL OFF HEAT, Thermostat Switch
COMBUSTION AIR for TIGHT buildings
COMBUSTION GASES & PARTICLE HAZARDS
COMBUSTION PRODUCTS & IAQ
COMPLETE COMBUSTION, Stoichiometric
CREOSOTE FIRE HAZARDS
Curved Brick Chimneys - Sulphation
CONDENSING BOILERS/FURNACES DAMAGE
CONVECTOR HEATERS - HYDRONIC COILS
DEFINITION of Heating & Cooling Terms
DIAGNOSTIC GUIDES A/C / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DIRECTORY of OIL TANK EXPERTS
DRAFT HOODS - gas fired
DRAFT MEASUREMENT, CHIMNEYS & FLUES
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS
DUST, HVAC CONTAMINATION STUDY
DUST SAMPLING PROCEDURE
ELECTRIC HEAT, DIAGNOSIS, REPAIR
ELECTRIC MOTOR DIAGNOSTIC GUIDE
ELECTRIC MOTOR OVERLOAD RESET SWITCH
ELECTRICAL POWER SWITCH FOR HEAT
EVAPORATIVE COOLING SYSTEMS
FAN, AIR HANDLER BLOWER UNIT
FAN AUTO ON Thermostat Switch
FAN, COMPRESSOR/CONDENSER UNIT
FAN CONVECTOR HEATERS - HYDRONIC COILS
FAN LIMIT SWITCH
FILTERS, AIR for HVAC SYSTEMS
FILTERS, OIL on HEATING EQUIPMENT
FIRE SAFETY CONTROLS
FIREPLACES & HEARTHS
FLAME COLOR, BLUE vs YELLOW COMBUSTION
FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
FLUE SIZE SPECIFICATIONS
FLUE VENT CONNECTORS
FREEZE-PROOF A BUILDING
FUEL OIL TYPES & CHARACTERISTICS
FUEL UNIT, HEATING OIL PUMPS
GALVANIC SCALE & METAL CORROSION
GAS BURNER Flame & Noise Defects
GAS FIRED WATER HEATERS
GAS PIPING, VALVES, CONTROLS
GAUGES ON HEATING EQUIPMENT
GEOTHERMAL HEATING SYSTEMS
HEAT EXCHANGER LEAK TEST
HEAT LOSS in BUILDINGS
HEAT LOSS DETECTION TOOLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEAT LOSS R U & K VALUE CALCULATION
HEAT PUMPS, DIAGNOSIS, REPAIR
HEAT TAPES & CABLES on Roofs for Ice Dams
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS METHODS
HEATING LOSS DIAGNOSIS-BOILERS
HEATING LOSS DIAGNOSIS-FURNACES
HEATING OIL CLOUD WAX GEL POINT
HEATING OIL EXPOSURE HAZARDS, LIMITS
HEATING OIL - OLD, USEABLE?
HEATING OIL PIPING TROUBLES
HEATING OIL SHELF LIFE
HEATING OIL SLUDGE
HEATING OIL USAGE RATE
HEATING SMALL LOADS
HEATING SYSTEM INSPECT DIAGNOSE REPAIR
HEATING SYSTEM INSPECTION DETAILS
HEATING SYSTEM NOISES
HEATING SYSTEM TYPES
HIGH EFFICIENCY BOILERS/FURNACES
HOT WATER HEATERS
HOT WATER IMPROVEMENT
INSULATION INSPECTION & IMPROVEMENT
LOW VOLTAGE BUILDING WIRING
LOW VOLTAGE TRANSFORMER TEST
LP & Natural Gas Safety Hazards
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH
NATURAL GAS COMBUSTION PRODUCTS
NO HEAT - BOILER
NO HEAT - FURNACE
NOISE / SOUND DIAGNOSIS & CURE
NOISE AIR CONDITIONER / HEAT PUMP
NOISE, DUCT VIBRATION DAMPENERS
NOISE, HEATING SYSTEMS
NOISE, WATER HEATER
ODORS FROM HEATING SYSTEMS
OIL BURNER FUEL UNIT
OIL BURNER INSPECTION & REPAIR
OIL BURNER NOISE SMOKE ODORS
OIL BURNER NOZZLE & ELECTRODES
OIL BURNERS, RETENTION HEAD
OIL BURNER SOOT & PUFFBACKS
OIL FILTERS on HEATING EQUIPMENT
OIL FILTER MISSING
OIL FUEL TYPES & CHARACTERISTICS
OIL HEAT FIRE SAFETY CONTROLS
OIL LINE CLOGGING FIX
OIL LINE QUICK STOP VALVES
OIL LINE SAFETY VALVES
OIL FILL PIPE LEAKS
OIL PUMP FUEL UNIT
OIL SPILL CLEANUP / PREVENTION
PLASTIC HEATER VENT
PULSE COMBUSTION HEATERS
PRESSURE REDUCING VALVES
PRESSURE REGULATOR, WATER
PUFFBACKS, OIL BURNER
PUMPS, PONY PUMPS
RADIANT HEAT Floor Mistakes to Avoid
RADIANT HEAT TEMPERATURES
RADIANT SLAB FLOORING CHOICES
RADIANT SLAB TUBING & FLUID CHOICES
REFRIGERANTS & PIPING
RELIEF VALVE LEAKS
RELIEF VALVES - TP Valves on Boilers
RELIEF VALVES - STEAM TP VALVES
RELIEF VALVES - Water Heaters
RELIEF VALVES - Water Tanks
Reset Switch - Heater Primary Control
Reset Switch Broken - Quick Repair
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY HAZARDS & INSPECTIONS
SAFETY HAZARDS GUIDE
SAFETY, HEATING INSPECTION
SAFETY RECALLS CHIMNEYS VENTS HEATERS
SOLAR HEATING SYSTEM DESIGNS
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS
STACK RELAY SWITCHES
STAIN DIAGNOSIS on BUILDING INTERIORS
STEAM HEATING SYSTEMS
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
THERMAL TRACKING & HEAT LOSS
THERMOSTATS, HEATING / COOLING
TRANSITE PIPE CHIMNEYS & FLUES
VIDEO GUIDES: Heating System Videos
VIDEO GUIDES - InspectAPedia.com
WATER HEATER SAFETY
WATER HEATERS for HOME HEATING USE?
WATER HEATER NOISES
WATER HEATER SCALE - De-Liming Procedure
WATER HEATER SCALE PREVENTION
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
Residential heating boiler inspection, installation, diagnosis, &repairs: we describe how to inspect & troubleshoot all types of residential heating systems and we describe just about every common heating system defect or operating problem. The articles listed on the left side of this heating boiler home page describe the components of a home heating system, how to find the rated heating capacity of an heating system by examining various data tags and components, how to recognize common heating system operating or safety defects, and how to save money on home heating costs. We include product safety recall and other heating system hazards. The limitations of visual inspection of heating systems are described.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved.
If you have no heat, see HEATING LOSS DIAGNOSIS-BOILERS.. You can also continue your heating furnace diagnostic procedures with the articles at Related Topics headed under BOILER CONTROLS & SWITCHES. If your heating system is fired by an oil burner, you can go directly to those diagnostics at OIL BURNER INSPECTION & REPAIR. Gas burners are discussed at GAS BURNER Flame & Noise Defects.
The article below explains hot water heating boilers (hydronic systems). If your building is heated by steam, see STEAM HEATING SYSTEMS. If you don't know what kind of heat your building uses, we explain how to figure out the answer in more detail at HEATING SYSTEM TYPES.
Warm Air Heating Systems - Furnaces: If the heat in your building is provided by warm air that flows out of ceiling, wall, or floor air supply registers into the occupied space, or if your heating system uses a water-to-air heating system then the air which warms the living space is probably being delivered through large or small diameter ducts, registers, air filters, and a furnace blower, and the air is being heated by a gas, oil, or electric furnace, or perhaps by a heat pump or a geothermal system. See FURNACE CONTROLS & SWITCHES.
Hot Water or Steam Heating Systems - Boilers: If the heat in your building is provided by warm or hot metal radiators, heating baseboards containing finned copper tubing, or wall convectors that look like a radiator but contain finned copper tubing, or if heat is provided by flexible rubber, plastic, or metal tubing run in building floors or ceilings, then the warm or hot water circulating in those devices is probably being delivered by piping circulating water heated by a heating boiler, or possibly by a steam boiler or a heat pump or geo-thermal system. See BOILERS, HEATING and RADIANT HEAT Floor Mistakes to Avoid.
What's the difference between a heating boiler and a furnace?
In general, a "heating boiler" heats the building using hot water. A "furnace" heats a building using hot air or "warm air". Don't confuse the two since their means of making and distributing heat, their controls, and their equipment are mostly different. For a detailed guide to inspecting and maintaining warm air heating systems or furnaces, see FURNACES, HEATING.
What's the difference between a hydronic (hot water) boiler and a steam boiler?
A "steam boiler" delivers heat to the occupied space in the form of steam: the boiler literally "boils" water and sends steam rising up through steam riser pipes and through steam radiators in the occupied space. If your heating radiators have valves which hiss and let air escape as heat is coming on your heat is probably being delivered in pipes which circulate steam from the steam boiler up through radiators in the occupied space. For a detailed guide to inspecting and maintaining steam heat systems see STEAM HEATING SYSTEMS.
How is heating boiler efficiency or economy measured? What does boiler AFUE mean?
Each model of heating boiler is assigned an AFUE number. AFUE is an abbreviation for Annual Fuel Utilization Efficiency. In short, the AFUE tells you, for each dollar you spend on energy for heating by gas, oil, or another fuel, just how much of your dollar shows up inside the occupied space of your building as heat.
Details are at AFUE DEFINITION, RATINGS
What are we looking at when we're talking about oil-fired hot water heat? It's helpful to form a simple working definition that helps understand the system. An oil-fired forced hot water or "hydronic" heating system is a collection of components which heats a building by heating and then circulating hot water through heat-radiating devices located in the occupied space.
A "heating boiler" is a steel, copper, or cast iron "box" of hot water, connected to a loop of pipe (and radiators or baseboards) which runs around through the living area. The same physical water stays in the boiler and is circulated by a pump so that heat is delivered to the living area. Burning oil makes hot gases which are used to heat the water before being exhausted outside. Pumps move fluids through the system. Safety controls of various types are installed at various points protect against a number of potential hazards.
How does a Heating Boiler Work?
We discuss how heating boilers work in step-by-step detail at BOILER OPERATION DETAILS
This approach broadens the scope of the heating system inspection and it may aid in heating system defect recognition or problem diagnosis, for example by observing that a heating boiler is located in a small, air-tight room (possible combustion air problems), or that the furnace is quite close to the oil storage tank.
Below we give the basics of heating system inspection using the physical location "map" of components to assure completeness. See full details of heating system inspection procedures provided at HEATING SYSTEM INSPECT DIAGNOSE REPAIR
Continue with Hydronic Heating Diagnosis & Repair
If you have no heat, see HEATING LOSS DIAGNOSIS-BOILERS
If your heating system is fired by an oil burner, you can go directly to those diagnostics at OIL BURNER INSPECTION & REPAIR.
Gas burners are discussed at GAS BURNER Flame & Noise Defects.
Frequently Asked Questions (FAQs) about hot water heating system inspection, installation, troubleshooting, repairs
Question: does my Burnham residential boiler require annual service?
Does my Burnham residential boiler need annual service. It worked fine last season. - Dick 9/19/11
Yes, Dick, there is no Santa Claus; your heating boiler needs annual service not only to assure safe, reliable operation, but because without an annual cleaning, particularly for oil fired heating boilers, my experience is that the cost of operating the equipment will be significantly greater - the improvement in operating efficiency of an oil fired heating boiler following annual cleaning and adjustment can be significant - I've seen a 33% reduction in operating cost following cleaning and adjusting a dirty oil fired boiler or furnace.
Question: Boiler trips circuit breaker - intermittent failure of boiler to turn on
I have a 3 year old Peerless WV-DV boiler, 1 zone (thermostat), 2 circulator pumps, no valves, serviced annually. This year when turning thermostat up the boiler refused to come on. The 20 amp circuit breaker had tripped. It wouldn't reset, kept tripping immediately. I turned the power switch off at the boiler, reset the breaker, turned the power back on at boiler, turned thermostat up and boiler came on normally. I then, over the course of an hour, turned thermostat up and down, each time boiler shut off and came back on normally. Then is got warm here for a few days, didn't use. When it got cold again, same problem, I had to turn off power at boiler, reset breaker, turn power back on at boiler, then boiler works. I also replaced the breaker in case that was a problem. So what is the issue here? Any help would be appreciated. - Scott Moberg 10/14/11
Question: hot water recirculating loop is not maintaining temperature
having a problem with a hot water recirculating loop from boiler to storage tank with tempering valve to building. not able to maintain proper temp. any ideas? - Vivek 10.26/11
Question: how do I figure out the age of my heating boiler or furnace?
Would like to know the age of a National U.S. Radiator boiler, Boiler # 109-5. It is a five section boiler, with Crane forged into the sections. Only can see the two end section numbers, F10900201 and F10900301. Just curious, thanks for any help. - Gary Forbes 11/5/11
Gary, see AGE of HEATERS, BOILERS, FURNACES (article links listed at Related Topics ) for tables, charts, and links to books that give means to decode the age of heating and cooling equipment using the model and serial number.
Question: no heat on upper floor, no air bleeder valves
its just the upper floor and i don't have bleeder valves at the base board the expansion tank at the boiler is hard to tell how full it is - Luke 11/10/11
Luke, at AIRBOUND HEAT SYSTEM REPAIR by WATER FEED VALVE we describe a variety of ways to get air out of an air-bound hot water heating system.
Question: books on troubleshooting residential heating boilers
are there any books on troubleshooting residential boilers & how to wire them - Kevin 1/12/12
Kevin, at References, related articles we list a variety of books on heating system installation & troubleshooting; when I was servicing heating systems, in addition to attending trade school for absolutely-required practical knowledge and theory, I found too that quite a few manufacturers gave away free booklets and pamphlets with excellent detail about their equipment. And don't forget to check the installation and service manual for the specific equipment you are examining.
Question: How do you add antifreeze to a boiler? What kind of antifreeze do we use in a boiler? How much do you add?
Don, some help on winterizing a boiler as well as a whole building is at Winterize- Heat Off Procedure.
The basic procedure is to use a pony pump (a transfer pump - see PUMPS, PONY PUMPS) to add antifreeze (buy at your local heating supplier) to the water mix in the boiler until our test gauge shows that we've got enough antifreeze in the system to protect down to at least a bit below the lowest expected temperature.
The service tech uses a pony pump connected to a boiler drain or zone drain valve, typically using a pair of washing machine hoses to form a loop between a boiler drain, a bucked of antifreeze & water mix, and a zone drain.
The pump pushes antifreeze into the system from the bucket; keeping the drain end of the second hose below the level of antifreeze in the bucket avoids introducing air into the system and thus avoids having to bleed that air out.
Complete details about how to add anti-freeze to a hot water heating boiler and system are found at ANTIFREEZE for BOILERS where we explain what kind of anti-freeze to use, how much to add, how to get it into the system, and what are the effects of antifreeze on heat transfer and heating system operation and costs.
Question: How to diagnose gurgling sound coming from boiler and radiant heat tubing
I have radiated heat at night tub gurgles and boiler makes noise - Jeff 10/8/12
Jeff, gurgling in hot water heating lines is often due to air in the piping. Check for a leak and for an air purging device that is not working.
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