Guide to Heating Oil Burner Fire Safety Controls & Electrical Switches InspectAPedia® -
Where should oil line fire safety valves and check valves be located?
Where should the heating system electrical shutoff switches be located?
Links to articles on other oil heat safety controls
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This document describes defects in heating oil safety valves and electrical switches. All of these oil storage tank and piping installation defects 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.
OIL BURNER SAFETY SWITCHES & CONTROLS- How to Inspect & Report Oil Heat or Oil Hot Water Heater Defects by Visual Inspection
GUIDE to MISSING or DEFECTIVE or "off on reset" SAFETY CONTROLS & SWITCHES at the Oil Tank & Oil Burner: Electrical shutoff switches for heat and oil line shut off valves
Where do we Install an Electrical Switch to Turn off the Oil Burner?
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:
An oil burner electric power service shutoff switch near the oil burner for the service technician
An oil burner electric power emergency shutoff switch remote from the oil burner, best located at the top of the basement stairs or in the nearby living space (you don't want to have to enter a smoke-filled basement to turn off the heating system in an emergency).
How & Where do We Install a Fusible-Link Firematic™ Oil Safety Valve?
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 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 degF 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 SAFETY VALVES 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.
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 oil line safety valve on the oil line at the burner.
Fire Safety for Two-Line Oil Piping Systems
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 a 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 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 SAFETY VALVES 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.
The valve shown at left should not be used as a check valve in the application we just discussed. This is a Webster 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. 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.
Other oil heat equipment safety controls and devices are listed in the links below.
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Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Dave Ferris - M&S Environmental Systems, Dutchess County, New York. Mr. Ferris was an
HVAC expert. Personal communication to DJF 1987. Remove the firematic or
fusible oil supply line valve on return oil-line side - in case of fire if this
one closes first the pump continues to run, blows its seal, and sprays oil all
over the fire. Proper installation is to have a fusible link valve only on the
supply side, and to install a check valve on the return line to prevent
back-siphonage from the tank.
Thanks to Rick Johnston for pointing out that the more likely cause of a fire safety valve in the return oil line is a burst seal on the fuel unit 4/6/2009
"The Oil Safety Valve (Service)", Charles Bursey, Sr., Fuel Oil News, February 2006 (Still trying to get the full article - October 2008 - DF) Charles W. Bursey Sr. can be reached at F.W. Webb Co. www.fwwebb.com/
"Installation Information for Suntec A-2000, A-7000 Single Stage and B-8000 two stage fuel units"Suntec Industries, 60 Aberdeen Drive, Glasgow KY 42141, 270-651-7116 (1725 rpm black label, 3450 rpm white label)
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