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HEATING SYSTEMS

AFUE DEFINITION, RATINGS
AGE of CHIMNEYS & FIREPLACES
AGE of AIR CONDITIONERS & HEAT PUMPS
AGE of HEATERS, BOILERS, FURNACES
AIR FILTERS for HVAC SYSTEMS
AIR HANDLER / BLOWER UNITS
AIRBOUND HEAT SYSTEM REPAIRS
ANTIFREEZE for BOILERS

BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER VALVE, HEATING SYS
BACKFLOW PREVENTER, HEATER WATER FEEDER
BACKUP HEAT for HEAT PUMPS
BANGING HEATING PIPES RADIATORS
BAROMETRIC DAMPERS
BASEBOARD HEAT
BLEVE EXPLOSIONS
BLOWER FAN OPERATION & TESTING
BOILERS, HEATING
BOOKSTORE - InspectAPedia

CAPACITORS for HARD STARTING MOTORS
COOL OFF HEAT, Thermostat Switch
COMBUSTION AIR
COMBUSTION GASES & PARTICLE HAZARDS

DEFINITION of Heating & Cooling Terms
DIAGNOSE & FIX AIR CONDITIONER / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DIRECTORY of OIL TANK EXPERTS
DRAFT MEASUREMENT, CHIMNEYS & FLUES
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS

FAN, AIR HANDLER BLOWER UNIT
FAN LIMIT SWITCH
FILTERS, AIR for HVAC SYSTEMS
FILTERS, OIL on HEATING EQUIPMENT
FIRE SAFETY CONTROLS
FLOODED HEATING EQUIPMENT REPAIR
FREEZE-PROOF A BUILDING
FUEL OIL TYPES & CHARACTERISTICS
FUEL UNIT, HEATING OIL PUMPS
FURNACES, HEATING

GAUGES ON HEATING EQUIPMENT

HEAT LOSS INDICATORS
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 SHELF LIFE
HEATING OIL SLUDGE
HEATING OIL TANKS
HEATING OIL TYPES & PROPERTIES
HEATING OIL USAGE RATE
HEATING SYSTEM INSPECT DIAGNOSE REPAIR
HEATING SYSTEM NOISES
HEATING SYSTEM SERVICE & MAINTENANCE
HEATING SYSTEM TYPES
HOT WATER HEATERS

LOW VOLTAGE BUILDING WIRING

MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH

NO HEAT - BOILER
NO HEAT - FURNACE
NOISE, HEATING SYSTEMS
NOISE, WATER HEATER

ODORS & SMELLS DIAGNOSIS & CURE
ODORS FROM HEATING SYSTEMS
OIL BURNERS
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 ODORS, LEAKY OIL TANK PIPING
OIL PUMP FUEL UNIT
OIL SPILL CLEANUP / PREVENTION
OIL TANKS
OIL TANK GAUGES
OIL TANK LEAKS & SMELLS
OIL TANK PIPING & PIPING DEFECTS
OIL TANK WATER REMOVAL

RADIANT HEAT
RADIATORS
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, HEATING INSPECTION
SAFETY RECALLS, Chimneys, Vents, Heaters
SOOT on OIL FIRED HEATING EQUIPMENT
STACK RELAY SWITCHES
STAIN DIAGNOSIS on BUILDING INTERIORS
STEAM HEATING SYSTEMS

THERMAL TRACKING & HEAT LOSS
THERMOSTATS, HEATING / COOLING
THERMOSTATS, WATER HEATER

VIDEO GUIDES: Heating System Videos
VIDEO GUIDES - InspectAPedia.com

WATER HEATERS

ZONE DAMPERS
ZONE VALVES

More Information

Oil burner oil line switch (C) Daniel Friedman Guide to Heating Oil Burner Fire Safety Valves: fusible link oil safety valves & vacuum-operated OSVs
     

  • OIL LINE SAFETY VALVES - What is an Inline fusible-link oil line fire-safety valve (OSV), and how are they used on oil fired heating equipment: boilers, furnaces, and water heaters?
    • DEFINITION of Fusible-Link Oil Safety Valves (OSVs)
    • LOCATION of OSVs
    • Manufacturers List for OSVs
    • OPEN or SHUT POSITION of OSVs
    • OIL LINE SAFETY VALVE HAZARDS, MISTAKES
    • TWO LINE OIL PIPING VALVE & CHECK VALVE
    • VACUUM-ACTIVATED OIL SAFETY VALVES, OSVs & PRVs
    • CHECK VALVE LOCATION on an OIL LINE
    • DE-AERATORS Tigerloop™ & OTHER OIL LINE PRIME PROTECTION DEVICES
  • OIL LINE SAFETY VALVE TURN DIRECTION to OPEN or SHUT - separate article
  • FIRE SAFETY CONTROLS - separate article
  • OIL LINE QUICK STOP VALVES - separate article
  • Questions & Answers about heating oil control valves and fusible link safety valves
  • References

Click to Show or Hide Related Topics

  • HEATING OIL TYPES & PROPERTIES - home
  • OIL BURNERS - home
  • OIL TANKS - home
  • OIL TANK PIPING & PIPING DEFECTS - home
    • CAULK OIL PIPE ENTRANCES
    • DEFINITIONS: OIL PIPING CONTROLS
    • DUAL OIL LINE 2 VALVES
    • DUAL OIL TANKS - PIPING
    • FIRE SAFETY CONTROLS
    • HEAT TAPE HAZARD ON OIL TANK
    • OIL FILL & VENT PIPING
    • OIL FILL PIPE EXPOSED
    • OIL FILL / VENT PIPE CAP LOST
    • OIL FILL & VENT PIPES UNDERSIZED
    • OIL LINE CLOGGING FIX
    • OIL LINE EXPOSED
    • OIL LINE LEAKS
    • OIL LINE QUICK STOP VALVES
    • OIL LINE SAFETY VALVES
    • OIL LINE SINGLE, UP HIGH
    • OIL LINE SINGLE ON BURIED TANK
    • OIL ODORS, LEAKY OIL TANK PIPING
    • OIL TANK FILL & VENT LINES APART
    • OIL TANK VENT PIPE MISSING
  • PUFFBACKS, OIL BURNER
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Guide to OSVs - Oil Line Safety Valves: this article describes check valves and fusible link oil safety valves used on oil piping at heating appliances as both a fire safety device and to assist in oil burner servicing. We explain the purpose of OSVs, which way to turn the OSV or oil line safety valve to open or close it, and we describe common oil line valve installation or use mistakes. We describe and explain the differences in function and use among fusible link fire safety valves (OSVs), vacuum operated OSVs and PRVs, oil line check valves, Tiger Loop and other oil system air removing devices, and oil delay valves or quick-stop valves that are also referred to as oil safety valves. We explain where each valve is installed and what it does. We include oil safety valve and check valve troubleshooting advice, and we describe defects in heating oil piping & control valves.

Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.

What is an OSV & How & Where do We Install a Fusible-Link Firematic™ Type Oil Safety Valve?

What are Fusible-Link Oil Safety Valves (OSVs) - definition

Oil line safty valve in the OPEN (oil flows) Position (C) 2013 Daniel FriedmanThe OSV or oil safety valve controls flow of fuel oil to the oil burner of oil-fired heating boilers, furnaces, and water heaters. This inline oil valve is intended to close automatically and thus stop the flow of oil in the oil line in the event of a fire.

When the oil safety valve is open to permit heating oil to flow its movable stem and thus its internal stop valve are under spring tension.

Because the valve includes a fusible link (a lead or other soft metal core), in event of a fire the fusible link melts and the internal spring pushes the valve stem down, closing the valve and stopping oil flow.

Closing the oil valve means that we stop feeding oil to the oil burner in the event of a fire in the area.

This article series explains the installation & use of Fusible Link Oil Safety Valves (immediately below), Vacuum-Activated Oil Safety Valves, OSVs & PRVs, Check Valves on Heating Oil Lines, and Tigerloop™ or similar oil line de-aerator/prime-protection devices. Oil delay valves, also called quick-stop valves and also referred to as oil safety valves, are discussed separately at OIL LINE QUICK STOP VALVES.

Where are OSVs usually Installed?

Oil burner oil line switch (C) Daniel FriedmanUsually the OSV is installed close to the oil burner both for safety reasons (close to heating equipment means close to a more likely fire source) and also for service convenience. In our photo you can see from left to right the OSV (red arrow), an oil filter, and the fuel unit and air intake for the oil burner. That vertical pipe below the fuel unit is the return line - so we know this is a two-pipe or two line heating oil set-up.

Sometimes additional stop valves or OSVs may be installed at other locations (such as at the outlet of an above ground oil storage tank, but the critical location is at the oil burner.

The Firematic™ fusible-link automatic oil line shutoff valve (photo at left) should only be present on the oil supply line. We explain below that installing an OSV on the return line of a two pipe oil system can lead to disasater. Instead we can install a simple one-way check valve on the oil return line.

Our photo at below left shows an example of a Firematic™ safety valve right at the oil burner. Synonyms people use for this valve include OSV, fire safety valve, oil line valve, Fire-o-Matic valve, Fusible link valve, oil line shutoff valve, oil safety valve, and Fireamatic valve.

Oil Line Safety Valve Manufacturers List - where to buy an OSV

Fusible link oil line valve (C) Daniel FriedmanThe 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.

At least three companies produce fusible-link inline oil safety valves (OSVs): ISP Automation (Firematic) [1], Asco Products (Emerson Industrial) [2], and a vacuum-activated OSV from Webster Fuel Pumps & Valves [3].

How to Tell if the Oil Line Safety Valve (OSV) is OPEN or SHUT

In our OSV photos below, the first photo (below left) shows the oil line safety valve in the OPEN positin - oil will flow when the threaded portion of the valve shaft extends fully up through the rotatable knob pointed to by my pencil. [Click any image to see an enlarged version. Thanks to reader Bernie Daraz for pointing out the need for these two photos]

Oil line safty valve in the OPEN (oil flows) Position (C) 2013 Daniel Friedman Oil tank drain valve leak (C) Daniel Friedman

In our heating oil line valve photo at above right the valve has been manually CLOSED - no oil will flow. The threaded valve stem has disappeared down into the valve body and has shut off the valve and oil flow.

Watch out: if (for example in case of a fire) the fusible link inside of an OSV has melted permitting the spring to close the valve, then from outside the valve may look as if it is in the open position - the threaded stem will still be poking out - but the valve has snapped and closed internally. Most likelyl you'll know this also because there will have been a fire or other horrible event that melted the OSV fusible link.

Which Way do I Turn the Oil Line Valve to Open or Close it to Permit or Shut Off Oil Flow?

  • OPEN: if the OSV is turned fully CCW (left to right) to Open Position = oil can flow
  • CLOSED: if the OSV is turned fully CW (right to left) to Closed Position = oil cannot flow
  • Details about exactly how to operate and which way to turn an OSV or oil line safety valve or Firematic valve are provided at OIL LINE SAFETY VALVE TURN DIRECTION to OPEN or SHUT

Oil Line Safety Valve Hazards, Mistakes, Problems

Other Oil Safety Valve SNAFUS & Warnings

Watch out: A simple oil line shutoff valve may not be a fusible-link safety valve. The simple shutoff valve might be any plumbing valve that can manually stop oil flow in the line, but it is not a safety device.

Make sure you've installed a fusible-link safety valve at each location where it's most needed - at each oil burner. Even when one of these valves is installed at the oil tank the proper place for this protection is on the fuel oil supply line right at the burner as well. Why?

In the event of a fire, if the return oil line valve closes before the supply line oil valve your oil burner pump may burst the oil line or it may cause a fuel pump gasket or seal to fail, leading to uncontrolled oil flow and perhaps worse, spray heating oil everywhere, possibly feeding the building fire. Thanks to Dave Ferris for this fire safety tip and thanks to reader Rick Johnston for adding clarification. (Note that not oil burners use both an oil supply and oil return line between the oil tank and oil burner.)

Suntec points out in their installation literature for fuel units (oil pumps for oil burners) that pressures over 10 psi on an oil inlet line (normally running at a vacuum) may damage the shaft seal on the pump - i.e., leak heating oil.

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.

Oil burner oil line switch (C) Daniel Friedman Oil tank drain valve leak (C) Daniel Friedman
  • Recommended (red arrow, photo above left): an automatic oil line shutoff valve on the oil supply line right at each and every individual oil burner: (a type that will shut off oil supply to the heating equipment in the event of a fire, such as a Fire-o-Matic™ valve) is shown in our photo at left.

    By every oil burner, we mean for example that if your heating system and also your hot water heater each has its own oil burner then each burner should have an oil safety valve. (As in our photo above left).
  • Oil-Tank-Only Valves are Not Recommended: A common but poor practice is to install an oil valve just at the oil tank or perhaps installing a single oil safety valve at the oil burner for the heating boiler but omitting the oil safety valve for the oil fired water heater in the same building.
  • A second oil line shutoff valve on the oil supply line at the oil tank (photo above right) is ok as long as you 've also provided the first oil safety valve at the oil burner(s). Some service techs install a second oil safety valve at the oil tank or at another remote location away from the oil burner, such as at the building wall where an outdoor oil tank line enters the building, or right at the oil tank (photo at above right - this oil tank valve is leaking).

    This second valve is helpful if it becomes necessary to replace the oil line between oil tank and oil burner. Although our photo above shows a fusible link oil valve at the oil tank, the oil line shutoff valve at the oil tank or at a location remote from the oil burner or other more likely fire sources can be a normal plumbing stop valve.

Fire Safety for Two-Line Oil Piping Systems

Improper use of two oil fusible link valves (C) D FriedmanWatch out: 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.

Our photo (left, red arrow) illustrates this hazard: you will see fusible link safety valves on both the oil feeder line (blue arrow, left side of photo before the oil filter canister) and the oil return line (red arrow, right side of the photograph).

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.

Guide to Vacuum-Activated Oil Safety Valves, OSVs & PRVs

Webster vacuum operated oil safety valve installation - Webster How are vacuum type OSVs different from fusible link OSVs?

Most residential heating equipment is supplied by oil piping that moves to from oil tank to oil burner by gravity (above ground oil storage tanks) and that is under negative pressure (a vacuum) when the oil burner is running: the oil burner fuel unit is pulling oil from the tank to the burner. Typically a spring-loaded fusible-link oil safety valve such as the Fireomatic type is used on those systems.

Vacuum-activated Webster OSV valves provide protection for pressurized oil line piping systems that may be found on central heating oil supply systems for multiple mobile homes, on commercial heating systems and at other installations in which a stand-alone heating oil supply pump is delivering oil to the equipment. Webster provides instructions for OSV use on both conventional gravity-fed oil fired heating equipment and pump-fed oil fired heating equipment.

Vacuum Operated Oil Safety Valves Protect Against Oil Spills

Webster's vacuum-activated OSVs provide protection against oil spills by preventing oil siphoning out of the oil tank should there be a break or leak in the oil piping between the oil tank and the oil burner(s). These valves are used with oil supply pump or booster pump systems and they also protect against excessive oil pressure at the oil burner inlet. Quoting Webster [4],

The OSV® valve will not open during fuel unit operation if there is any air leak in the the system between OSV® and burner that prevents development of the operational vacuum required.

Where to Install Vacuum Operated Oil Safety Valves OSVs

For vacuum-operated OSVs, unlike fusible link OSVs, an OSV device is installed not at the oil burner (since this is not a heat-activated fusible link device) but rather close to the oil tank, and an individual OSV and oil feed line is provided from the tank to each heating appliance. [Webster's sketch, above-left.] In the illustration shown above left (courtesy Webster Fuel Pumps & Valves [3].) the OSVs are at the oil tank and additional service shut-off valves are at the individual oil burners.

Watch out: Webster's instructions for OSVs include this warning:

Do not mount the oil safety valve more than three feet above the lowest point in the fuel pump inlet [in most residential cases this means the oil burner fuel unit], nor more than three feet above the lowest point in the fuel line connecting the OSV to the burner fuel pump. In-line mounting with the burner fuel pump inlet is recommended.

Failure to observe the above caution may result in siphoning action in the event of failure of the fuel line between the burner fuel pump and the OSV. [3]

Suntech's PRV Valves are OSVs that Prevent Oil Flow or Leaks When the Oil Burner is Not Running

The following description is adapted, parapthrased, and expanded from Suntec Industries information.[9]

A PRV valve, such as Suntech Industries Inc.'s Model PRV-38 is an oil safety valve that prevents oil from flowing out of an oil tank by gravity, or by siphoning action, when flow is not desired. At the inlet side of the PRV valve, oil can be supplied under pressure or under a vacuum (depending on whether or not the oil burner fuel unit is running). But the PRV will not open to allow oil to flow unless it senses a vacuum.

This means that oil will not flow past this valve unless the oil burner and its fuel unit are operating. The effect is that this valve prevents oil from flowing out of an oil tank under any other conditions.

Why is a PRV valve installed? Suppose you have a large, above-ground oil storage tank at a facility, and that a leak occurs in the oil piping between the tank and the oil burner. Even if the oil line was cut entirely, the PRV valve will keep oil in the tank. In essence, the PRV valve is an oil leak and spill preventer.

PRV Installation & Use Recommendations

PRV Valves are installed as close to the oil tank as possible. And no, we don't usually find a PRV valve installed on residential heating systems. The PRV is mounted with its cap "down" if it's in an area exposed to moisture, to keep moisture out of the valve body. But it will work just fine in any orientation. Suntec's installation instructions for PRVs recommend that the valve be protected by a system filter.

If the PRV is used in a centralized oil supply system that is supplying fuel to multiple heating appliances, or if you are installilng the valve on a system that uses oil flow booster pumps, each oil burner should have its own PRV valve, as Suntec explains, to insure against high system pressures.

When installing a PRV or other valves and controls on oil fired heating equipment, do not use teflon tape. The worry is that a fragment of tape enters the system where it can clog a check valve or injure a device. Instead use a non-hardening pipe dope. We use a non-hardening version of blue LeakLok that works very well on oil fired equipment.

When you are priming an oil fired heating appliance, that is, bleeding air out of the lines, you can speed the process by pressing down on an exposed stem to hold the valve in an open position. We need this feature because the fuel unit does not pull such a strong vacuum on the oil line if the line is full of air (such as at a new installation).

PRV valves and No-Heat Calls

If there is an air leak in the piping system anywhere between the PRV valve and the oil burner, and if the air leak is big enough to prevent the burner from pulling enough vacuum to open the PRV, the PRV will remain shut, no oil will flow, and the burner will of course not operate.

You can test for this condition by pressing the prime button described above and checking for oil flow. A pressure gauge installed on the system can also be used to monitor for leaks (can the system hold a vacuum when the fuel unit shuts off?). We discuss pressure testing oil lines in the article above where we discuss Oil Safety Valves. You can also pressure test the oil lines under positive pressure.

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.

Use a check valve instead. Check valves like this one permit oil to flow just in one direction. They do not close down in event of a fire. Installed on the oil return line a check valve permits oil to flow from the oil pump back to the oil tank. This makes service easier since we won't spill oil backwards out of the return line when working on the oil burner.

Check valves suitable for placement on the oil return line are available from various oil heat equipment producers including Webster.

Oil line check valve (C) Daniel Friedman
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.

Where do I Install a Tigerloop™ or similar oil line de-aerator/prime-protection device?

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 this device are found at Tigerloop and other Oil Line Devices to Maintain Prime and Simplify Oil Piping

Frequently Asked Questions (FAQs) about Fusible Link Oil Safety Valves (OSVs) on Heating Equipment

Question: Freeing up a stuck oil line control valve?

I think I have a valve that doesn't seem to turn off when fully turned counter clockwise. Any idea why? - P.C.

Reply:

If you have a fusible link valve that doesn't seem to turn off you might try tapping the exposed end of the valve stem. I have found a stuck, or slow to close OSV on a few rare occasions. A gentle tap, not hard enough to damage threads, loosens it after which I open and close the valve a few times to convince myself it now moves freely. A burr on the brass interior or more likely internal sludge or debris could be the culprit.

Because at the oil burner the OSV is likely to be used at least once a year during service, that's a good opportunity to discover if the valve is not closing fully.

Questions or comments about this article

Questions & answers or comments about heating oil control valves and fusible link safety valves

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.

  • [1] Audels Oil Burner Guide, Installing, Servicing, Repairing, Frank D. Graham, Theo. Audel & Co., New York 1946, 1947, 1955 (out of print, copies occasionally available from antique book dealers and on EBay)
  • [2] Beckett Model SR Oil Burner Instruction Manual, R.W. Beckett Corporation, PO Box 1289, Elyria OH 44036 and R.W. Beckett Canada, Ltd., 430 Laird St., Guelph, Ontario, Canada N1G 3x7
  • [3] Thanks to Bottini Fuel service tecnician Bob for discussing the buzzing aquastat relay problem, 4/18/2012. 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
  • [4] Beckett Model SF Oil Burner Instruction Manual, op.cit.
  • [5] Sunstrand Corporation - Sunstrand Fuel Units, 4949 Harrison Avenue P.O. Box 7003 Rockford, Illinois 61125-7003 U.S.A. Telephone: (815) 226-6000 Fax: (815) 226-5399 http://www.sundstrand.com
  • [6] Sunstrand Transmission Service Manual, May 1974, web search 08/19/2011, original source: http://www.cushmantrackster.com/pay-pdfs/sundstrand.pdf - Sunstrand Series 15 hydrostatic transmissions
  • [7] Webster Fuel Pumps & Valves, Capitol City Tool, Inc., http://www.websterfuelpumps.com/
  • [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
  • [9] Suntec Model PRV-38 Oil Safety Valve Installation Information, untec 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/Form 2155 - PRV-38 Installation.pdf]. You can download this file from Suntec's website. ,
  • [10] Firomatic Globe Type Oil Line Valves & Lever Type Fusible Link Control Valves: ISP Automation, Inc., 1035 Old Georges Road, North Brunswick, NJ 08902, Phone: 866-383-3481, FAX 866-383-3482, Email: support@ispautomation.com
  • [11] Fusible link oil line control valves for commercial equipment: ASCO products by Emerson Industrial Automation, P.O.Box 160, 17 Airport Road Brantford, Ontario Canada N3T 5M8 Tel: (519) 758-2700 Fax: (519) 758-5540
  • [12] Fuel oil safety valves, Webster Fuel Pumps & Valves, 219 Hahn Road Frankfort, Ky. 40601, Tel: (800) 766-1233 Email: czahalka@cctoolinc.com (Curtis Zahalka Sales Mgr/Mkt /Cust Service/Tech Support/Webmaster ) web search 10/12/2011 original source http://www.websterfuelpumps.com/pdffiles/osv1.pdf
  • [13] Webster Service Technicians' Handbook, Webster Fuel Pumps & Valves, 219 Hahn Road Frankfort, Ky. 40601, Tel: (800) 766-1233
  • [14] "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/
  • [15] "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)
  • [16] Tigerloop: oil line de-aerator devices, Westwood Products Inc., 330 William St., PO Box 610, South River, NJ 08882-0610 - (732) 651-7700
  • [19] Thanks to reader Bernie Daraz for suggesting the need for clear photographs illustrating the OSV or oil line safety valve in the open and closed positions. Personal correspondence 2/15/2013.
  • Carson, Dunlop &
Associates Ltd., TorontoCarson, 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.
  • 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
  • Thanks to reader T.R. for suggesting clarity on where oil safety valves should or should not be installed and for discussing the proper hook-up location for the Tigerloop and similar oil line prime protection & air removal devices. April 2011.

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

  • Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
  • Home Reference Book - Carson DunlopThe 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.

  • GO TO Carson Dunlop's Home Study Course Information - How to Become a Home Inspector: Carson Dunlop's nationally recognized Home Study Course, selected by ASHI the American Society of Home Inspectors and other professionals and associations. This website author is a contributor to this course.
  • GO TO Carson Dunlop's Home Study Course Information - How to Become a Home Inspector: Carson Dunlop's nationally recognized Home Study Course, selected by ASHI the American Society of Home Inspectors and other professionals and associations. This website author is a contributor to this course.
  • GO TO Carson Dunlop's Home Study Course Information - How to Become a Home Inspector: Carson Dunlop's nationally recognized Home Study Course, selected by ASHI the American Society of Home Inspectors and other professionals and associations. This website author is a contributor to this course.
    Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd
  • 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.

  • Oil Tanks - The Oil Storage Tank Information Website: Buried or Above Ground Oil Tank Inspection, Testing, Cleanup, Abandonment of Oil Tanks
  • Abandon a Buried Oil Tank, How To - Abandoning Commercial Underground Tanks, Russ Brauksieck, ASHI Tech. Journal, Vol.3 No.1 Spring 1993, P. 40-41 [Reprint]
  • Primer on Petroleum Bulk Storage Tanks & Petroleum Contamination of Property Paul H. Ciminello, ASHI Tech. Journal, Vol.3 No.1 Spring 1993, p 35-39
  • Petroleum Bulk Storage J. Sibblies, NY State DEC, Advice to Home Owners and Home Inspectors about Oil Storage Tanks - summary from ASHI Chapter Seminar.
  • ...

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