4 Possible Reasons Your HVAC Heater Isn't Heating

Posted on: 26 January 2015

When outdoor temperatures drop and indoor temperatures threaten to join them, few things bring more comfort than a reliable central heating system -- except when that system stops being so reliable. If you're huddled under a mound of blankets right now because your heater has suddenly decided to take the winter off, rest assured that many heater issues can be dealt with by their owners. Here are four things you can check on your heater to discover -- and quite possibly correct -- the cause of the problem.

1. User Error

This one may be embarrassing to own up to, but you should always admit the possibility that someone in your household may have done something silly with the heater settings. For instance, when you're stumbling around in the middle of the night trying to find and adjust your thermostat, it could be all too easy to switch the device to "Off" instead of "Auto" by accident. The thermostat could also be set to a lower temperature than you thought.

2. Electrical Failure

An HVAC system takes its operational cues from electrical impulses. If your heater isn't receiving instructions, you need to troubleshoot the electrical sources and connections.

  • If your thermostat isn't getting power, it won't relay the necessary commands to the system. Try turning the fan on from the thermostat. If you get results, the problem lies elsewhere. If the fan doesn't turn on, then check the electrical circuit that powers the thermostat (or change the batteries, if the thermostat runs on battery power).
  • If the thermostat works but the furnace doesn't, check to see whether the circuit breaker that controls the furnace has been thrown or the fuse needs replacing. This will be a separate breaker or fuse than the one that governs the air conditioning components.

3. Furnace Problems

If the fan blows only cold air, then the furnace may be malfunctioning. If you have an electric furnace, the issue may be a faulty heating element, a wiring disconnection, a short circuit, or a bad piece of electronics. A gas furnace might have been switched off, in which case you can simply switch it on again, or it might have a closed gas valve. On older gas heaters, the pilot light may need re-lighting. Both electric and gas heaters can also suffer from a blower motor failure that requires the attention of a heating repair specialist.

4. Ventilation Blockages

Sometimes a heating system can't transfer the heat it generates to your ductwork because its ventilation filter is clogged with dust and debris. This filter may be either permanent or disposable. Remove a permanent filter from its slot, clean all the gunk out of it, and then return it to its original position. Throw a disposal filter away and then replace it with another of the same dimensions.

Not every central heating problem can be accounted for in a quick troubleshooting session or fixed by the homeowner. If you're still stumped by the fact that your heater doesn't heat, professional heater repair services can come to your rescue. Good luck -- and in the meantime, bundle up warm!