InspectAPedia ^®

Guide to Heating & Cooling Electrical Power Switches
InspectAPedia^®  -    

• A guide to finding and using electrical power switches for heating and cooling systems
• Where do we find the emergency-off switch for heating furnaces and boilers?
• What are the basic components of hot air heating systems?
• Troubleshooting heating system furnace controls
• How to inspect & repair hot air heating systems - Furnaces

Here we describe the usual location and function of electrical switches that control power to all types of heating equipment. If your building has lost heat, checking that the heating equipment is actually turned "on" at all of these switches is a first step in diagnosing the problem. This website answers most questions about central heating system troubleshooting, inspection, diagnosis, and repairs. We describe how to inspect residential heating systems to inform home owners, buyers, and home inspectors of common heating system defects.

The articles at this website describe the basic 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.

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 PARTS LIST 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, see  FURNACE CONTROLS & SWITCHES. If your building uses steam heat see STEAM HEATING SYSTEMS.

Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution. © Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

A Guide to Finding & Using Electrical Power Switches to Turn On or Off Heaters for Furnaces & Boilers, Heat Pumps or Electric Furnaces or Air Conditioners

Electrical power switches on heating and cooling systems: where will the power switches be located, how do we know if we have turned on power to the heating or cooling system? Our page top photo shows a typical emergency off switch for a heating system. Our photo at left shows a fuse box that is used to accomplish the same purpose, though this older switch is more likely to be found near the entry to a basement where heating equipment is located. Electrical switches that turn off electric power that operates any type of heating system: furnace, boiler, steam boiler, heat pump, electric heat, are required for both safety and for service. An emergency off switch for the building heating system should be found outside of the basement or other boiler or furnace room location and accessible so that an occupant can, in an emergency, turn off heat without having to enter a possibly smoky or dangerous area. A second electrical "off" service switch should be found on or very close to the heating equipment itself. This second service switch is used by the heating service technician. A third electrical switch or fuse turns off power to the heating equipment service at the building electrical panel. If a circuit breaker has tripped or a fuse has blown on the heating equipment's electrical circuit, you may be able to restore heat at the electrical panel. But for safety reasons it is important to determine why the fuse blew or the circuit breaker tripped. If you replace a fuse or re-set a circuit breaker and the fuse blows or circuit breaker trips again, do not restore electrical power to that circuit - call a service technician to diagnose and repair the problem.

How to Identify, Reset, or Adjust Heating or Air Conditioning System Controls and Switches

For details about the setting, re-setting, or function of the controls and switches commonly found on hot air heating systems see these articles:

• Hot Air Heating Furnace Basic Operating Steps
• Guide to Heating System Components:
• Air Bleeder Valves for Hot Water Heating Systems: Radiators, Baseboards, Convectors
• Aquastats Heating Boiler Primary Controls: A guide to Aquastats for control of hot water heating boilers and tankless coils
• Cad Cell Relays on oil fired furnaces or boilers as flame sensors & safety devices
• Check Valves Guide to check valves and backflow preventers on hydronic hot water heating systems gas or oil fired
• Draft Hoods on gas fired heating equipment, function and safety
• Draft Regulators & barometric dampers on oil fired heating equipment
• Expansion Tanks Guide to pressure control and expansion tanks on hydronic hot water heating systems gas or oil fired
• Fan Limit Switch on hot air furnace heating systems gas or oil fired
• Flue Gas Spill Switch on gas fired heating equipment sense combustion and protect from blocked flues
• Gas Piping, Valves, Controls including gas regulator assembly and other controls
• Mixing Valves: Guide to mixing valves on hot water heating systems and radiant heat systems
• Power Switches to turn on or off heaters for furnaces & boilers, oil & gas fired, heat pumps or electric furnaces or boilers
• Relief Valves - TP Valves: A guide to temperature and pressure relief valves & safety controls on hot water and steam heating systems
• Stack Relay Switches Explained on oil fired furnaces or boilers as flame sensors & safety devices
• Thermostats & Heat Controls for furnaces & boilers, oil & gas fired, heat pumps or electric furnaces or boilers
• Water Feed Valves: A guide to water-feeding/pressure-reducing valves on hot water and steam heating systems
• Zone Dampers: A guide to automatic or electrical zone dampers in heating or air conditioning ductwork
• Zone Valves: A guide to zone valves for heating zone control on hot water heating systems

Share this Article      

...

Technical Reviewers & References

• InspectAPedia.com^® - Daniel Friedman
• InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also include a list of recommended books for the specific article topic as well as other references, and information sources.
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Additional technical contributors & reference sources for this article are listed below.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

HEATING SYSTEMS
BLUERAY Recall
BOILERS, HEATING
  BOILER OPERATION DETAILS
  BOILER PARTS LIST
  BOILER CONTROLS & SWITCHES
  BOILER LEAKS CORROSION STAINS
  BOILER OPERATING PROBLEMS
CARBON MONOXIDE/DIOXIDE
CARBON MONOXIDE WARNING
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CHIMNEYS & Flues - Asbestos Transite Pipe
DUCT INSULATION - Asbestos Paper
DUCTS - Asbestos Transite Pipe
DUST FROM HVAC?
ELECTRIC HEAT
ELECTRICAL POWER SWITCH FOR HEAT
FAN CONVECTOR HEATERS - HYDRONIC COILS
FLUE VENT CONNECTORS
FREEZE-PROOF A BUILDING
FURNACES, HEATING
  DUCT SYSTEM DEFECTS
  DUCT & AIR HANDLER ODORS
  FURNACE CONTROLS & SWITCHES
  FURNACE OPERATION DETAILS
  HEAT EXCHANGER LEAKS
GAS PIPING, VALVES, CONTROLS
HEAT LOSS INDICATORS
HEAT LOSS PREVENTION PRIORITIES
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS
HEATING LOSS DIAGNOSIS-BOILERS
HEATING LOSS DIAGNOSIS-FURNACES
HEATING OIL CLOUD WAX GEL POINT
HEATING OIL EXPOSURE HAZARDS, LIMITS
HEATING OIL SLUDGE
HEATING SYSTEM INSPECTION DIAGNOSIS REPAIR
HOT WATER HEATERS
HOT WATER IMPROVEMENT
INSULATION & VENTILATION INSPECTION & IMPROVEMENT
NO HEAT - BOILER / FURNACE DIAGNOSIS
ODORS FROM HEATING SYSTEMS
OIL BURNERS
OIL BURNER INSPECTION GUIDE
OIL BURNER NOISE SMOKE ODORS
OIL BURNER SOOT & PUFFBACKS
OIL FUEL TYPES & CHARACTERISTICS
OIL TANK LEAKS
OIL TANK SLUDGE
OIL TANK TESTING
OIL TANKS, BURIED
PLASTIC HEATER VENT
RADIANT HEAT
RADIANT HEAT Floor Mistakes to Avoid
RADIANT SLAB FLOORING CHOICES
RADIANT SLAB TUBING & FLUID CHOICES
RADIATORS
Safety Recalls
  BLUERAY Recall
  CHIMNEYS & Flues - Asbestos Transite
  Goodman HTPV RECALL
  Lennox Furnace Manuals
  Lennox WARNING
  Weil McLain RECALL
SAFETY DURING HEATING INSPECTION
STEAM HEATING SYSTEMS
  Cad Cell Relay Switch Flame Sensors
  Low Water Cutoff Valves, Boilers
  Mixing Valves
  Relief Valves - TP Valves
  Sight Glass, Steam Boiler
  Pressure Switch, Steam Boiler
  Spill Switches
  Stack Relay Switch
  Steam Vents
  LOW WATER CUTOFF CONTROLS
  Water Feeder Valves, Steam
TANKLESS COILS
THERMAL EXPANSION of MATERIALS
THERMAL MASS in BUILDINGS
THERMAL MASS in UPSTAIRS
THERMAL TRACKING & HEAT LOSS
THERMOSTATS
Transite Pipes, Chimneys & Flues

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

• Our recommended books about building design, inspection, and repair, and about indoor environment testing, diagnosis, and cleanup are at the InspectAPedia Bookstore.
• ...

More Information on Building Diagnostic Inspections and Repairs

• Carbon Dioxide Gas Toxicity
• Carbon Monoxide Gas Toxicity, exposure limits, poisoning symptoms, and inspecting buildings for CO hazards
• Dust from HVAC? An Investigation of Indoor Dust Debris Blamed on a Heating/Cooling System Reveals Carpet Dust
• 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
• Plastic Heating Vent Pipe & Other Heating Safety Recall Notices
• Weil McLain Model GV Gas Boiler/gas valve CPSC recall/repair
• 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.)

InspectAPedia® Home & Site Map - Building & Environmental Inspection, Testing, Diagnosis, Repair, & Problem Prevention Advice: In-depth research & advice on diagnosing, testing, correcting, & preventing building defects & indoor environmental hazards. Unbiased information, no conflicts of interest.

The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems

Use this simple, economical mold test kit by following our instructions on how to collect and mail mold samples to our lab

Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.

Building Inspection, Problem Diagnosis, Forensic Investigation & Testing, Repair Consulting

Contact Daniel Friedman for website content suggestions or for fee-paid consulting