Original message
| shaz
 |  "furnace short cycling"
, posted Wed 14 Dec 22:15  
Hello all I am new to this forum Its nice to know I can use
the knoweledge base here. OK here goes got a service call today
for a pilot light out. no problem right noooooo I found a
lennox GH6D-80M mid 70's I guess seperate valves for pilot and main
got the pilot lit no prob made call for heat and nothing.checked
the voltage at the main and it was fine tried manually cycling the valve by removing the wire and intermittingly making contact
bad valve. Valve not available any more honeywell v80b1dj4x3
sooo I got a robert shaw 700-400 24 volt combo valve and repiped all. fired it up all was well for 5 mins then it started short cycling blower on 10-14 secs off 10-14secs burner running all the time. then shut down for 5 or so mins and repeat the same.
pulled the overlimit switch out and left it connected and same thing. Talking with the homeowner this was how it operated before
I did anything. Please did I miss something?? Ideas besides replacement. sorry for the long post jeff
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Replies:
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| pilight
| "Re(1):furnace short cycling" , posted Sat 27 Jan 15:25
The limit switch would allow the burner to operate, not the fan. If you jumped around the fan control and the blower was short cycling I would be looking at the motor. See if the bearings are getting worn by seeing if there is lateral play in the motor shaft. If the motor is getting hot, this would be a good indication of if the internal overload protectors are opening and de-energizing motor.
Also get a voltage stick or voltmeter to read if there is power to the motor at the point the motor stops. This should nail it.
Pilight
pilight
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| acefurnacefixer
| "Re(1):furnace short cycling" , posted Thu 15 Dec 06:49:
Did you re-adjust your heat anticipator setting?
P.S. This should be posted in the residential section.
Yes! I CAN fix that!
http://www.white-rodgers.com/common/ptech/thermo/Classic_80_prog_5_2.htm
[this message was edited by acefurnacefixer on Thu 15 Dec 06:50] |
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