Enviro M55 intermittently not responding to thermostat

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radiorental

Member
Mar 7, 2014
16
ma
I've been trying to debug this intermittent problem. Wondering if anyone has experience or can give guidance because I'm all out of ideas.

Enviro M55 insert. Installed for 3 years. Had this problem last season too.
Ecobee Smart SI wireless thermostat. Controls both the Stove (stage 1) and Oil furnace (Stage 2)
Ecobee controls two 24v relays that are connect to stove & furnace.

There's three modes on the M55, Manual / Auto / Auto on-off. I generally use Auto which will run the stove on the lowest setting until heat is call for. Everything will work as expected but then the M55 seems to stop responding to the t-stat. It will run on the lowest setting.

I have tested the wiring all the way up to the back of the stove and it's OK.

An interesting thing I've discovered is this;
If heat is being called for and the M55 is in Auto but running on the lowest setting. If I switch the M55 mode to manual it will switch from the lowest setting to whatever heat output setting it's set to (expected). Now if I switch back to Auto - It will obey the t-stat.

This is reproducible 100% of the time which would cast some doubt on the problem being intermittent faulty control board in the stove.

It seems like that might mean an intermittent fault in the control board, but I want to check in to see if anyone has experience with this issue.

thanks!
 
I've been trying to debug this intermittent problem. Wondering if anyone has experience or can give guidance because I'm all out of ideas.

Enviro M55 insert. Installed for 3 years. Had this problem last season too.
Ecobee Smart SI wireless thermostat. Controls both the Stove (stage 1) and Oil furnace (Stage 2)
Ecobee controls two 24v relays that are connect to stove & furnace.

There's three modes on the M55, Manual / Auto / Auto on-off. I generally use Auto which will run the stove on the lowest setting until heat is call for. Everything will work as expected but then the M55 seems to stop responding to the t-stat. It will run on the lowest setting.

I have tested the wiring all the way up to the back of the stove and it's OK.

An interesting thing I've discovered is this;
If heat is being called for and the M55 is in Auto but running on the lowest setting. If I switch the M55 mode to manual it will switch from the lowest setting to whatever heat output setting it's set to (expected). Now if I switch back to Auto - It will obey the t-stat.

This is reproducible 100% of the time which would cast some doubt on the problem being intermittent faulty control board in the stove.

It seems like that might mean an intermittent fault in the control board, but I want to check in to see if anyone has experience with this issue.

thanks!
Hi radiorental!
Roundabout suggestion, you could us two dedicated t-stats. My insurance company rep, suggested a separate t-stat.
Easier for us and family members.....Maybe another M55 owner can shed light on a dual t-stat setup.
Bill
 

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Hi radiorental!
Roundabout suggestion, you could us two dedicated t-stats. My insurance company rep, suggested a separate t-stat.
Easier for us and family members.....Maybe another M55 owner can shed light on a dual t-stat setup.
Bill
Thanks, that's an option but I don't think it gets to the heart of the problem. Even If I manually trigger the heat in test mode, the M55 is not responding.

I don't think the problem is with the ecobee. I just mentioned the 2 stage setup for completeness.

Also, I like the ecobee because I can control the thermostat remotely. Last night for example, we were over at friends so I was able to quickly adjust to away mode and then call for heat 30 minutes before we got home. You can't do that with standard t-stats.
 
Not familiar with the Ecobee thermostat, but could there be a swing temp setting it has to reach before it calls for heat?

Also, my wireless Skytech sometimes totally acts up depending where the remote is placed in the living room. I even think the crappy temp sensor in the remote unit stops reading temps correctly because the temp reading will be off by a few degrees from my trusty Honeywell indoor temp sensor/display. So I blow from compressed air at the sensor and that seems to fix it.
 
Hey there, I noticed you posted an issue where your pellet stove was intermittently not responding to your thermostat. Mine is now doing to the same thing. Did you ever solve your problem? Can you give me some guidance based on your experience?

Thank you!

My email is [email protected]

Conrad