If you live in a colder climate where there is snow, you should check your outside air intake pipe to make sure it is not covered in snow. The pipe needs to be clear in order for it to be able to draw air into the house. This simple tip may save you big $ on a service call.
What type of furnace do you have?electric
What type of furnace do you have?electric
It could be a thermocoupler, happened to my furnace in middle of night a few years ago.
No, it is preferable to use outdoor air which is then expelled rather than blowing indoor air out so new cold air replaces it.
If it's blowing intake-temperature air, either you've got the fan alone switched on or the heating part isn't working for some reason. If it's a gas furnace, the pilot light may have gone out, or the gas may be shut off somewhere (at the furnace itself, at the emergency shutoff for the house, or possibly at the main inlet). If it's blowing actually COLD air (colder than intake), then you've probably got central air and you've somehow managed to turn on the air conditioner.
Nothing as a furnace is scorhed air a BOILER is either water or steam and "Relief Valves" are for liquid thus either you have a boiler or your furnace is being flooded from an outside source
The burners are not igniting for some reason. Could be a few different things, call a plumber.
Turn up the inlet gas pressure on the furnace to create more BTUs.
Probably the flame sensor.
Is it blowing cold air only or not blowing any air at all.
You need to call a qualified heating contractor for service.
when running the heat-pump the air blowing from the heat ducts is not hot ( it's to cold for the heat-pump). you have a main furnace and it won't turn on ( is thermostat selected for this source), ( is the power switch for main furnace on ), ( is fuse for this furnace good). If these are good (check thermostat wiring at thermostat, and transformer).