Enviro Maxx convection blower

[Steeve.B]

Hello all,
I’m new here, I just purchased an Enviro Maxx pellet stove and installed it about 2 week ago. So far the stove work well and is a power house, it can easily heat my whole house. I have an heat distribution kit installed on the stove right now.

I have a question regarding the convection blower. With the HDK there is 3 new sensor, one of them appear to be a 120F fan sensor that it plugged in parallel with the original convection blower circuit. By that I mean that 120 volt from main appears to be going through the sensor, then back to the blower. So I guess that as soon as the heating duct part of the stove get to 120F the convection blower turn on?

My issue is that my stove is on the main floor and the convection blower is always running even when the stove is in first setting while no heat is required. In 2 week it has stopped maybe 4 time for less than 10 minutes. Is my sensor defective or is this normal behavior? I understand that with the HDK you want to circulate air but I wasn’t expecting it to be on all the time. Stove run on 1 maybe 70% of the time since I’m in high/low with a thermostat.

thank’s to anyone who will help me!

 

[Ssyko]

welcome Steeveb.
The added sensors for the HDK have been an issue since they have come out. Personally I don’t know why they even added them . Your convection blower should not be running if the stove is not up to temp. Either the sensor they sent with the kit is bad or the wires aren’t routed correctly. To test i would unhook that sensor and hook up the original and see if it still runs continuously. Also do a search here on the forums for HDK there are a lot of threads about it.

 

[Steeve.B]

Thank you,

Before buying this stove I have read almost all thread available on this forum regarding the stove and I was aware of the issue. I will search again but I don’t remember seeing one regarding this specific issue.

Usually the wiring issue come from the white wire and my dealer told me to hook them in series with the thermostat wich appears to work well.

 

[Ssyko]

Well going by the schematic it should not be running unless it trips the 120 snap disc. Have you tried running it without the hdk wires hooked up? I have a MAXX but I don’t have the hdk so my experience is limited.

 

[Steeve.B]

Tomorrow I will open the stove and check witch sensor is normally close and open. I will also take temperature reading with my ir thermometer near the sensor and try to bypass the fan sensor.

 

[Steeve.B]

I tested the sensor tonight. Unfortunately I couldn’t find my ir thermometers, I will search in even more tomorrow.

The 175 F control snap disk is normally close and hook in series with the thermostat. That mean that went the stove reach 175 F the sensor open and cut the signal from the thermostat and lower the stove to heat setting 1. This is counter intuitive because this usually happen on heat setting 4 or 5 where you need the most BTU hour.

Secondly the fan sensor is normally open when the stove is cool. Then during the first 10 minutes of the starting cycle the stove is hot enough for the sensor to close (I cannot verify the temperature currently). This take the 120v from main connection and send it to the convection blower in parallel to the regular circuit. Maybe the sensor open only when the stove is much cooler than 120 F after that?

I disconnected the fan sensor, taped the connection to not get electrocuted and the stove blower now appears to be running fine. To me this sound like either a bad sensor or a too low temperature sensor. I understand that with HDK you need to have air circulating but the air comming out on heat setting 1 is like 80 F at best when hooked that way.

 

[Ssyko]

are the original sensor's on the back of the stove still connected? I can't recommend this be done, but if it were my stove and i wanted it to work on a tstat i would hook the tstat to the control board and leave all the HDK wiring unhooked and out of the loop. the stove will reach temp and convection fan will come on as it should and send air out the HDK venting to your zones. it still has all the normal safeties in tact just a diff routing of air.

 

[Steeve.B]

are the original sensor's on the back of the stove still connected? I can't recommend this be done, but if it were my stove and i wanted it to work on a tstat i would hook the tstat to the control board and leave all the HDK wiring unhooked and out of the loop. the stove will reach temp and convection fan will come on as it should and send air out the HDK venting to your zones. it still has all the normal safeties in tact just a diff routing of air.

I’m thinking the same way as you do. All original safety sensor are still connected and I don’t plan to disconnect those. The second high limit sensor that came with the HDK don’t cause any issue so I will definitely keep that one.

I found my ir thermometer so tomorrow I will take some reading just in case my sensor would be defective.

By the way I did contact my dealer. The guy is really nice and appears to know a few trick. He own one Maxx too and told me his work the same way (fan always on) but he never bothered about it. I don’t think he will help me on that one.

 

[Steeve.B]

I tested my sensor today and it close the circuit at around 85-90 F. The sensor is definitely bad. My dealer came today to do some touch up on the stove paint. I showed him the evidence, he told me there more going on than this sensor and that there is other circuit that can turn the blower on

It looks like I’m on my own. I ordered a new sensor online so I should be able to test this soon.

For now I will run the stove in auto/off since it’s hot enough outside this week.

 

[ReidH]

I have an Enviro Maxx with the HDK.
What you are describing sounds like normal operation. The heat distribution kit will run the convenction blower whenever the stove housing temp is 120F or over. That is pretty much all the time as the housing is almost always 120f or hotter. The intention of the kit is to distribute heat using the convection fan through ducts. It the temp is too low, it switches off so that cold air is not distributed.
It will do other intersting things such as switch to low fire if the temp of the housing is too high so that the ducting does not get too hot.

Reid

 

[Steeve.B]

This the way I anticipate things to work. Since I tested the sensor and it appears to be closing to soon I ordered a new one to see. Once I get it I will post a reply so anyone can know if it fixed the issue.

I don’t plan to bypass the sensor because my stove is running fine otherwise. It just bother me when it’s circulating cold air.

 

[Steeve.B]

I replaced my fan sensor today while cleaning my stove and it appears to have fixed the issue. Now the fan will run per stock stove spec when it’s below 120F. Then when it hit 120F the fan turn on even if it’s in first heat setting. I would say that the fan run for 10 min every 30 min in first heat setting and it pump hot air when it’s turned on.

I also had a vibration coming from within the stove. After testing I found out that the main wiring harness was resting on the convection blower and rubbing. I would suggest anyone having this issue to investigate and fix this issue with cable tie. I think that the wire could wear out after a while if they were left that way.