M441 gets room up to temp, then quits

[HayZee518]

monitor 441

it is normal for the heater to overshoot the setpoint by 4 or even 6 degrees, then it'll go into shutdown mode. all this time the combustion blower should be running. the combustion blower is the FIRST to come on and the LAST to shut down. The circulating fan goes on and kicks up to high speed, then a lower speed as the setpoint is reached.
When you grasp the thermister, naturally the read temperature WILL GO UP and the heater will shut down. If you were to disconnect the thermister, the heater will default to 42 degrees and stay there no matter what the setpoint is set at. In other words it will run wide open.

[gearsoup]

Well, that's the thing. It doesn't overshoot the temp by 4-6 degrees. It just hangs out at the prescribed temperature and constantly runs.

[hawkins111]

Economy Plus

What about the Economy Plus button, is it ON?

Tom

[gearsoup]

I have tried it in auto mode, which does not permit economy plus to be active, I've tried it in normal mode, and in economy plus mode. Same results. Gets to temp, and then just stays there. Burner stays running, 2 bars showing on the burner status lights....

Right now, after 6 hours, called for temp is 70. Actual temp is 74. Still running. Now, granted, my garage has gone without heat for a week, so there is a chill coming off the cement. The thermistor is about 4 feet off the ground

[hawkins111]

Economy Plus

Since the heater is in a shop you will benefit from the Economy Plus feature. There is less cycling of the heater this way. Remember that the stove will not shut off until the room sensor reads 12 degrees more than the set, i.e., set 60 and the stove will shut off at 72. With a concrete floor it may take a long time to get the room up to temp. There are a number of factors to give thought to here. Insulation, window, height of ceiling and how many times the door is open, all make a difference. You may think about a fan up high in the room blowing down. This will move some of the already heated air downward. This may even save you some fuel.

Tom