Furnace runs (forces heat) and does not shut off. This is a heat-only system. Replaced Honeywell thermostat with an Ace Hardware Heat Only thermostat. Have adjusted heat anticipator to the setting listed on the furnace (.04). Still runs and does not shut off.

Thanks for any help.

If the furnace runs all the time and will not shut off by turning down the thermostat then the thermostat wiring might be shorted. Disconnect the RH or R and the W terminal wires from the furnace at the terminal strip. If you remove the wires and the furnace shuts off then the thermostat wiring is the problem and usually that means the wiring has shorted out.

Thank you for your reply. Would you consider talking to my boyfriend by phone while he looks at the furnace? Thanks for considering. My email:


No posting of email addresses please.

Did you disconnect the wire (s) and do the test mentioned in my other post?

Yes.
Think I should mention that prior to it running constantly that it would do what I have seen mentioned on this website as a "short cycle". It would run, cut off for a short period (several seconds or a minute or so) and then turn on again.

After my boyfriend disconnected the thermostat wires, it still runs constantly.

Post the complete exact model number. I will see if I can look it up to see what parts it contains and which part might be causing the problem.

Thank you.
Model FEHA-015HA-01
s/n FE9110-82272

There is a CLG after Nordyne, think that is the series.

Is it just the blower that is running constantly, or are the burners also burning constantly? Is the house getting really hot, getting really cold, or just staying nice and comfy?

If that unit is a electric furnace then the heat sequencer section that controls the blower is stuck closed. It will probably look like this. If this is what is in the unit take the plastic end of a screwdriver and tap it gently a time or two and see if the blower goes off. Naturally turn the power off first.

This is a heat-only furnace. Not central air, not heat pump. I don't know if the model and s/n indicate the age of the furnace, but I do know that the trailer is late 70's-early 80's.

mygirlsdad77: blower runs constantly, heats up to around 70 or so (where thermostat is set), but does not quit blowing.

As mentioned before the sequencer OR contactor that controls the unit might be stuck shut. This happens when the contacts weld themselves together and on an older unit this happens quite a bit since the contacts have been well used.

I have no wiring diagram for that old of a unit but I know where you can get help since they are mobile home heating professionals. Post to the below link under Nordyne. They are good guys and have parts if you need them . Sorry I could not be of more assistance.

Index page (http://www.mobilehomerepair.com/phpbb/index.php)

Thank you so much for your assistance.

No problem