Heatmor Furnace question

[DManWI]

I am new to this forum so here is a little run down, I live in the Northern part of Wisconsin & have owned a Heatmor 400CSS Furnace for around 10 years, it heats 2 houses & 2 hot water heaters & we do love it. Other then having problems with the pumps at first, that was fixed by my dealer switching brands of pumps. Then replacing 2 of the furnace fans, we have really had no other problems. But in the last month we have been losing water some times, there is no signs of a leak, but today my daughter just happened to go out & check the furnace & came in the house & told me it sounded like the furnace was boiling. We normally only go out to the furnace once every 12 hours to fill it and I should mention that the thermometer doesn't't work, I have been meaning to replace it but keep forgetting. Anyway I went out and the water was definitely boiling and the fan was still running! I shut the switch off & when I turned it back on the fan stayed off. So I am sure a switch stuck, my question is what switch and where is it? There is a controller in the front & the back, which 1 controls when the fan turn on & when it shuts off? What should the settings for each controller be set at?
I greatly appreciate any help!

 

[November Wolf]

It sounds to me like your aquastat is not working correctly. I have a CB and mine is set at 175 on and 185 off. I don't have a fan on mine but the principal is the same. Good Luck.

 

[DManWI]

Thank you much for the info. Is that the one in the front or in the back? I was able to find my owners manual, and from what I can tell the front controller is for the fan on/off & the back one is a back up in case the front one malfunctions. Does that sound right?
Thanks again!

 

[November Wolf]

Your setup is different than mine. I only have one controller.

Hopefully some of the Heatmor owners will chime in on this one.

 

[Marklambert61]

Heatmor isues

You might want to carefully check your door seal and ash clean-out seal...

Air leaks can cause the issue you describe because after the control stops the induction fan and the boiler continues to get air too burn from the leaks.

Checking the aquastat is easy just monitor the temp the blower turns on and off compared to the reading in the temp gage. I have seen this issue a few times in older stoves.


Mark

 

[DManWI]

Thanks to you all for the help, first thing tomorrow I am replacing the temperature gage & I am going to see if I can replace just the piece that the degrees are on on the front aquastat controller. I have a feeling I do need to replace the door gasket also.
Thanks again for the input, I will try and post my end results.

 

[barnyardman]

I have the model 200, it also has a high temp switch set at 200 deg. that will shut the fan off if the aquastat fails.

 

[cleanburn]

^^in that picture is the aquastat and the high limit. Sounds to me like your aquastat is bad too....