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OIL STORAGE TANKS - home
OIL STORAGE TANKS - home
ABANDONING OIL TANKS
ABOVE GROUND OIL TANK (AST) GUIDE
BURIED OIL TANK (UST) GUIDE
DIRECTORY of OIL TANK EXPERTS
FUEL OIL TYPES & CHARACTERISTICS
HEATING OIL CLOUD WAX GEL POINT
HEATING OIL EXPOSURE HAZARDS, LIMITS
HEATING OIL SLUDGE
HEATING OIL TYPES & PROPERTIES - home
HEATING OIL USAGE RATE
HOME BUYERS GUIDE TO OIL TANKS
ODORS FROM HEATING SYSTEMS
OIL SPILL CLEANUP / PREVENTION
OIL TANK ABANDONING PROCEDURE
OIL TANK AGE
OIL TANK FAILURE CAUSES
OIL TANK GAUGES
OIL TANK INSPECTION & TROUBLESHOOTING
OIL TANK LEAKS & SMELLS
OIL TANK LEGAL ISSUES
OIL TANK LIFE
OIL TANK PIPING & PIPING DEFECTS
OIL TANK PRESSURE
OIL TANK REGULATIONS
OIL TANK REMOVAL COs
OIL TANK SAFETY
OIL TANK SLUDGE
OIL TANK CODES & STANDARDS - Detailed List
OIL TANK SPILL CLEANUP / PREVENTION
OIL TANK SUPPORT
OIL TANK LEAK TEST METHODS
OIL TANK TESTING & REMOVAL COs
OIL TANK WATER CONTAMINATION
This document describes defects in heating oil and oil burner safety controls, safety valves and electrical switches. All of the oil storage tank and piping installation defects described here can easily be found by visual inspection.
Beyond the costly problem of leaky oil piping, this document lists other important safety or oil-fired equipment operational defects in home and light commercial heating oil storage and piping systems.
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OIL BURNER SAFETY SWITCHES & CONTROLS- How to Inspect & Report Oil Heat or Oil Hot Water Heater Defects by Visual Inspection
The list of oil heat safety controls that follows also provides a guide to determining where there are missing or defective "off on reset" safety controls & switches at the Oil Tank & Oil Burner, beginning with electrical shutoff switches for heat or fossil fuel fired appliances and followed by oil line shut off valves.
[Click to enlarge any image]
Because some controls are used in common on hot water heat, hot air heat, and steam boilers, readers should see these other articles:
see BOILER CONTROLS & SWITCHES, and
also see BOILER COMPONENTS & PARTS for a detailed list of heating boiler controls, other heating system components, parts such as circulator pumps & draft regulators.
If your building uses warm air heat,
If your building uses steam heat
Carson Dunlop's sketch shows an electrical switch to turn off the oil burner and a manual oil line valve, both of which should be located away from the oil burner.
An oil fired heating system should have the following safety controls and valves installed:
The Firematic fusible-link automatic oil line shutoff valve (photo at left) should only be present on the oil supply line. This is a manual or automatic valve that will stop the flow of oil in the oil line.
This valve controls flow of fuel oil to the oil burner of heating boilers, furnaces, and water heaters.
Fusible link Oil Valve: Oil line safety valves have a lead or other soft metal core that melts and closes the valve so that the system won't keep feeding oil to the heating equipment if the area is on fire. See our photo at below left for an example of a Firematic™ safety valve right at the oil burner. Synonyms: Fire-o-Matic valve, Fusible link valve, oil line shutoff valve, oil safety valve, and Fir-o-matic (aka "Fireamatic") valve.
The standard oil safety valve used at the oil burner and often found also at the oil tank is the Firematic™ fusible link safety valve. The Firematic™ oil line valve can be installed in ANY position - (vertical, horizontal, upside down) at least that's what we were taught and what we have seen - the valve is spring loaded.
In a fire a lead core melts at 165°F and a spring in the valve assembly snaps the valve shut to assure that the heating system does not feed oil to a building fire. It has to work in any orientation.
See OIL LINE SAFETY VALVES, OSVs for details about the operation and use of this double duty-valve, used both as an oil piping supply-line shutoff valve and as a fusible link valve for fire safety.
SAFETY warning: If the oil line fire safety valves are missing or are not at the right location, we recommend immediate installation of a Fire-o-matic™ type fusible link oil line safety valve on the oil line at the burner.
Fireomatic ™ or Firomatic™ (or its successors and possibly other companies) produced a Firomatic Thermal Switch TS-150 series (or other brand) electrical safety switch that interestingly uses a similar spring-loaded fusible switch to cut off electrical power to a heating appliance (boiler, furnace, water heater) in the event of a fire.
Details about this device are at FIREMATIC FUSIBLE ELECTRICAL SWITCH
If two oil lines are used to supply an oil burner, Do NOT install an automatic oil line shutoff on the return oil line between the oil burner and the oil tank.
Use an OIL LINE CHECK VALVE instead. The automatic oil line shutoff valve should only be present on the oil supply line. Further explanation is below.
SAFETY WARNING: If oil line valves are missing or are not at the right location there is risk of system malfunction, oil leaks, and fire damage. We recommend installation of a Firematic fusible link (Fire-o-matic)™ type oil line safety valve on the oil line at the burner. This valve controls flow of fuel oil to the burner, and has a lead core which melts and shuts the valve, stopping the flow of oil in event of a fire in the building.
Even when a fusible link oil line valve is installed at the oil tank, the proper place for this protection is right at the burner as well. A valve in that location also makes servicing the heating equipment easier, faster, and cleaner.
Where do we Put the OSV or a Check Valve on a Heating Oil Line?
If two oil lines are used to supply an oil burner, install a fusible link oil line shutoff valve only on the oil supply line at the oil pump on the oil burner.
Do NOT install an automatic oil line shutoff on the return oil line between the oil burner and the oil tank.
See OIL LINE SAFETY VALVES, OSVs for details about this double duty-valve, used both as an oil piping supply-line shutoff valve and as a fusible link valve for fire safety.
Most sources also advise against installing a check valve on the return oil line - a topic we discuss ad nauseam over
Watch out: The valve shown at above left should not be used as a check valve in the application we just discussed. This is a Webster vacuum-operated OSV & requires a vacuum to open. If installed in the return line the valve would be pressurized, not open, cause the shaft seal to rupture or blow out & result in a major oil leak. Thanks to reader Rick Johnston for adding clarification.
Tigerloop™ and other Oil Line Devices to Maintain Prime and Simplify Oil Piping
If your oil burner uses a Tigerloop™ oil-line de-aerator (photo at left) to remove air or foam from the incoming oil line, the company notes that UL requires a fusible link oil valve installed in the (bottom) center (inlet) port of the Tigerloop™ device.
Tigerloop™ is an oil de-aerator installed at the oil pump (fuel unit) on an oil burner. It can help avoid losing prime on heating oil lines if there is a problem with air leakage into the oil piping.
Watch out: Tigerloop™ adds that you should never install an oil line shutoff device between the de-aerator device and the oil pump. Shown is the Tigerloop S220. A variation is available, the Tigerloop-ultra™ S-220-8 that incorporates an oil filter as well.
The manufacturer, Westwood, indicates in an article quoted from Fuel Oil News magazine that using the Tigerloop™ model TN device permits omission of the return oil pipe traditionally used with buried or distant heating oil tanks.
Also see OIL LINE SAFETY VALVES, OSVs for more information about check valves, fusible link safety valves, and oil line de-aerators
Watch out: Tigerloop™ warns that you should never install an oil line shutoff device between the de-aerator device and the oil pump.
Or as reader T.R. clarifies: ... I've been reading about TigerLoop oil fuel line de-aerators. When they are used, the manufacturer recommends that the fusible valve near the burner be attached at the inlet of their de-aeration device.
Details about a suspected leak in oil line piping where a de-aerator or oil line air removal device is installed are in a Q&A discussion found at OIL LINE PIPING LEAKS or select a topic from the More Reading links shown below.
Reader Comment: advice about oil burner emergency switches & their wiring
2 Feb 2015
The "emergency" oil burner shutoff switch must be wired into the "burner supply circuit", according to NFPA 31. It is different from the "service switch" on the unit, which must be at or near the unit.
As mentioned in the article, the identified "emergency" switch must be located outside the boiler room and generally outside the door to the cellar steps, if the boiler is in the basement. That way the switch can be turned off without opening the door, and serves as a marker for which door is the one to the basement.
Many installers simply run the appliance power feed through the "emergency" switch, which means it ALSO turns off any sidewall vents, circulators, fans, thermostats, and other devices powered through the appliance controls -- not just the burner.
The NFPA is presently evaluating whether such an installation is safe, let alone proper, under the existing Code.
Thanks NHFireBear - we've added your note here and at ELECTRICAL POWER SWITCH FOR HEAT. We can use all possible editing assistance. - Ed.
Watch out: It an interesting that if we shut off a blower fan on a furnace while the heat exchanger is still quite hot, the result could be a cracked (and thence unsafe) heat exchanger. On the other hand, if there is a building fire, particularly orignating in the furnace or boiler room, we hardly want to keep a furnace blower fan running.
Continue reading at AQUASTAT CONTROL or select a topic from the More Reading links shown below.
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