Thermostat help please

[Jack72]

Thermostat help please/furnace
« on: Today at 03:28:45 AM »
My OWB runs to my forced air furnace   It's been fine the last four years  now just before the OWB thermostat gets almost to temp it shuts off which it's still calling for heat so it turns on for 15 seconds and I hear the thermostat click now it's up to the desired temp now the furnace shuts off and stays off until the next call for heat like its suppose to like its short cycling           I changed the thermostat and thought it was good now it's doing it again with the new one. Any suggestions would be appreciated



Thanks   Jack

[dave_dj1]

If your talking about the hot air furnace blower short cycling I would check the high limit control, they are know to go bad and cause this. If you have a snap disk instead I'm not familiar enough with them to give you an honest answer but I would guess they could do the same.
dave

[John R]

If your talking about the hot air furnace blower short cycling I would check the high limit control, they are know to go bad and cause this. If you have a snap disk instead I'm not familiar enough with them to give you an honest answer but I would guess they could do the same.
dave

Only thing you can do with a snap switch is replace it.

[DeepCreek]

If your talking about the hot air furnace blower short cycling I would check the high limit control, they are know to go bad and cause this. If you have a snap disk instead I'm not familiar enough with them to give you an honest answer but I would guess they could do the same.
dave

I had an AC unit that had a Snap Disc limit switch. It failed at least once a year. IMHO, they are junk. At least that's been my experience.

[lineguy82]

You can check the snap disc with a continuity tester and a lighter. When it's cool it should show closed, if not it's bad. If it's good and you put the lighter to the disc it should open.

[Jack72]

I think I might of messed up the first couple days on the install I have a downdraft furnace I did not put a 3 way zone valve in to bypass around the exchanger when it's not running     I did turn my shut off temp 10 degrees down. which I do not prefer but it hasn't acted up since I turned down the temp.

I think everything is just getting to hot with that coil being constantly hot.   Thanks for everyone's suggestion but I'm going to try this first

Jack