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AIR CONDITIONING & HEAT PUMP SYSTEMS
BACKDRAFTING HEATING EQUIPMENT
BACKUP HEAT for HEAT PUMPS
BANGING HEATING PIPES RADIATORS
BLOWER FAN OPERATION & TESTING
BOOKSTORE - InspectAPedia
BTU USAGE MONITORS
CARBON MONOXIDE - CO
CIRCULATOR PUMPS & RELAYS
DIAGNOSE & FIX AIR CONDITIONER / HEAT PUMP
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DRAFT REGULATORS, DAMPERS, BOOSTERS
DUCT SYSTEM & DUCT DEFECTS
ELECTRIC HEAT, DIAGNOSIS, REPAIR
ELECTRIC MOTOR DIAGNOSTIC GUIDE
FAN, AIR HANDLER BLOWER UNIT
FLOODED HEATING EQUIPMENT REPAIR
FLUE SIZE SPECIFICATIONS
GAS BURNER Flame & Noise Defects
GAS PIPING, VALVES, CONTROLS
GEOTHERMAL HEATING SYSTEMS
HEAT PUMPS, DIAGNOSIS, REPAIR
HEATING COST SAVINGS METHODS
HEATING OIL PIPING TROUBLES
HEATING OIL TANKS
HEATING SYSTEM NOISES
HEATING SYSTEM TYPES
LP & Natural Gas Safety Hazards
MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES
MOTOR OVERLOAD RESET SWITCH
NOISE, HEATING SYSTEMS
ODORS FROM HEATING SYSTEMS
OIL FILTERS on HEATING EQUIPMENT
OIL ODORS, LEAKY OIL TANK PIPING
OIL SPILL CLEANUP / PREVENTION
PLASTIC HEATER VENT
PUFFBACKS, OIL BURNER
RELIEF VALVE LEAKS
Reset Switch - Heater Primary Control
RESET SWITCH - ELECTRIC MOTOR
Reset Switch - Stack Relays
SAFETY, HEATING INSPECTION
SAFETY RECALLS, Chimneys, Vents, Heaters
SOLAR HEATING SYSTEM DESIGNS
SOOT on OIL FIRED HEATING EQUIPMENT
STEAM HEATING SYSTEMS
THERMOSTATS, HEATING / COOLING
VIDEO GUIDES: Heating System Videos
WINTERIZE A BUILDING
WOOD, COAL STOVES & FIREPLACES
WOOD STOVE SAFETY
Troubleshoot cold radiators, baseboards, convectors in hot water heating systems: this article describes the diagnosis & repair of cold "hot water" heating baseboards, convectors, radiators, or "hot water" radiators. We provide articles that help in diagnosing and repairing no-heat problems with each types of hot water or steam or fan convector heat delivery systems.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
If your heating system uses steam radiators or steam convectors see COLD STEAM HEAT RADIATORS for help in diagnosing and fixing steam radiators that won't get hot.
This website answers most questions about all types of heating systems and gives important inspection, safety, and repair advice. If you don't know what kind of heat your building uses, we explain how to figure out the answer at HEATING SYSTEM TYPES. If your heating system is not working properly, see NO HEAT - BOILER. Our page top heating system illustration is provided compliments of Carson Dunlop Associates.
If none of your heating radiators, baseboards, etc. are getting hot, start your diagnosis of the problem at NO HEAT - BOILER / FURNACE DIAGNOSIS. It may be that your boiler is simply not running, has lost power, is switched off, or that the thermostat is not calling for heat.
If you have heat in some areas but not others we discuss diagnosing baseboard heat problems below, followed by a discussion of radiators and convector unit problems for both hot water and steam heat.
Make sure that your room thermostat is set to a temperature higher than the temperature in the room - so that it is calling for heat. (See THERMOSTATS.)
Make sure that your heating boiler is working, that is that the heating boiler turns on and off normally. A hot water heating boiler may not turn on immediately when you turn up the room thermostat: if the water temperature in the boiler is already above the aquastat's cut-in temperature the circulators will send hot water to the radiator and the boiler will turn on later when its temperature is dropped by returning water from the cooler radiators in the building.
If your heat is provided by baseboards there will not normally be individual shutoff valves at those devices, but if your system uses one circulator and provides multiple heating zones (and thermostats) there will be zone control valves (usually near the boiler) that are opened or closed by the room thermostat(s).
Air-Bound Baseboard Heating Zone Diagnosis
Once your thermostat is calling for heat and the heating boiler has been running for ten minutes or more, just feel the baseboard. Don't cut your fingers on the fins, and don't bend them if you can help it.
If some sections of baseboard are not easy to access that's ok - you can simply feel the start and the end of a section of baseboard to determine where the loop of heat piping is hot and where along the system the baseboard piping first feels cold.
Our photo (left) shows an older finned copper tubing baseboard system with the end-cover removed - it's easy to just touch the copper pipe to feel its temperature - hot or cold, that's all we need to know.
If just some sections of an individual zone or loop of heating baseboard are not getting hot, feel along the piping entering and leaving each section of baseboard in each room to find which sections are hot and which are cold - this is a first diagnostic step in determining what's wrong.
If your heat is distributed entirely through one zone (one thermostat, one loop of heating piping & baseboards) and if part of that loop is warm (usually just the beginning portion of the loop), then there is a good chance that your heating zone or loop is air-bound.
We provide detailed, step by step procedures for diagnosing and curing an air-bound hot water heating system, beginning at AIRBOUND HEAT SYSTEM REPAIRS. Also see heating baseboard air bleed valves discussed at Air Bleeder Valves for more details. Since on many hot water heating systems a key air bleeding or air vent point is at the air scoop or air separator closer to the boiler, see Air Scoops Purgers Separators.
Thermostat, Zone Valve, or Circulator Pump No-heat Diagnosis for Baseboard Heat
If your heating system is divided into multiple zones of baseboards or a mix of baseboards and radiators: If the heating boiler is running and some baseboard sections or rooms are hot but others are not, first check to see if your heating system uses multiple thermostats and multiple heating zones.
It may be that the thermostat controlling the "cold" rooms is not calling for heat or is not working. See THERMOSTATS.
If your heating baseboard is installed over a carpeted floor, be sure that the carpeting has not blocked the air inflow space under the bottom edge of the metal baseboard cover. Blocking this air intake will drastically reduce the heat output from your heating baseboards, thus increasing your heating bill.
If your heat is provided by individual hot water radiators or convector units, usually there is a control valve at each radiator or convector. Make sure that the control valve at the heating radiator is "open" or "on". In the "cold radiator" diagnosis article below we include links to additional detailed articles that will help you correct a problem with heating baseboards or radiators that are not working:
How to Bleed Radiators of Trapped Air
If your heating system uses steam radiators or steam convectors see COLD STEAM HEAT RADIATORS for help in diagnosing and fixing steam radiators that won't get hot. Excerpts from that article are found below.
Make sure that your room thermostat is set to a temperature higher than the temperature in the room - so that it is calling for heat.
Make sure that your heating boiler is working, that is that the heating boiler turns on and off normally. A steam boiler will usually turn on right away in response to the thermostat being turned up or on a call for heat.
Make sure that the control valve at the heating radiator is "open" or "on" as we describe just below. Details are at RADIATOR VALVES & HEAT CONTROLS.
Frequently Asked Questions (FAQs) about how to fix a cold radiator
Questions & answers or comments about troubleshooting cold radiators, convectors, baseboards on hot water heating systems.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.