Enviro 55M FS

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brianbess

New Member
Nov 10, 2024
16
Alburgh, VT
I bought a used Enviro M55C FS (Serial Number 223603) earlier this year and I am in the process of installing it in my garage. I was told by the former owner that it was functional before it was removed. Well that was not the case.

I have been making progress. There were 4 defective push-buttons on the control board, I replaced those. The convection blower squirrel cage blower had come apart from the end bearing, I repaired that.

I powered it up and it started to come to life! Pellets were dropping, the igniter was glowing a nice color of orange, the exhaust blower was working and the pot stirrer was rotating. We had ignition and flames! After a while, the convection blower came on.

I have been looking for the sequences of operation for this stove, but I can't find what the model number is for my control board or main board so as able to select the sequence chart. I have attached some pictures of what my boards look like.

There are some other quirky things happening, but I would like to run through the sequences first and then document what is or is not happening.

Thanks for your help
 

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  • [Hearth.com] Enviro 55M FS
    M55 Control Board.webp
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  • [Hearth.com] Enviro 55M FS
    M55 Main Board.webp
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I powered it up and it started to come to life! Pellets were dropping, the igniter was glowing a nice color of orange, the exhaust blower was working and the pot stirrer was rotating. We had ignition and flames! After a while, the convection blower came on.
This all sounds normal
See this manual your board is a DHC 4110
see pages 11 and 28 through 31
hope this is what you are looking for
 
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I bought a used Enviro M55C FS (Serial Number 223603) earlier this year and I am in the process of installing it in my garage. I was told by the former owner that it was functional before it was removed. Well that was not the case.

I have been making progress. There were 4 defective push-buttons on the control board, I replaced those. The convection blower squirrel cage blower had come apart from the end bearing, I repaired that.

I powered it up and it started to come to life! Pellets were dropping, the igniter was glowing a nice color of orange, the exhaust blower was working and the pot stirrer was rotating. We had ignition and flames! After a while, the convection blower came on.

I have been looking for the sequences of operation for this stove, but I can't find what the model number is for my control board or main board so as able to select the sequence chart. I have attached some pictures of what my boards look like.

There are some other quirky things happening, but I would like to run through the sequences first and then document what is or is not happening.

Thanks for your help
Thanks! I'll check it out!
 
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Thanks! I'll check it out!
Well, I finally had a chance to work on my Enviro M 55CFS. That link was very helpful.
Here is a little timeline of events & conditions.
  • 2:15 Powered up stove, placed on a heat level 5
  • 2:30 We had ignition
  • 2:35 #3 light came on, I pressed the on/off button, and jumped the Exhaust Temperature Switch, convection blower began to run. The temperature as measured at the Exhaust Temperature Switch was ~108 and would not climb any higher. I think that the switch closes at 140 on temperature rise and opens at ~120 on temperature fall.
  • I was reading a temperature of ~190 degrees at the outlet of the heat ex-changer tubes.
I have included a picture of the fire as well as a picture of the air closure plates inside the stove. It is like the stove is not pulling in enough air. There is no blockage of the exhaust, there is only ~8' of straight pipe. The air intake is not vented to the outdoors, but can get plenty of air inside my garage. Is there a procedure for setting the position(s) of the air closure plates? I'm getting closer!
I have included a picture of the ash pan door, I am missing a part for the latch. Does anyone have a picture or a part number for the part that I am missing?
 

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  • [Hearth.com] Enviro 55M FS
    20250126 Enviro Stove Air.webp
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  • [Hearth.com] Enviro 55M FS
    20250121 Enviro Flame .webp
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  • [Hearth.com] Enviro 55M FS
    20250121 Enviro Ash Pan Door Latch.webp
    220.9 KB · Views: 25
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Is the stove pipe going straight up through the roof? When was the last time it was removed and cleaned? When was the last time the combustion blower was removed and cleaned along with it’s chamber? Setting the stove is pg 10 in the Manual

The flame settings are available in the Tech Manual
 
...
I have included a picture of the ash pan door, I am missing a part for the latch. Does anyone have a picture or a part number for the part that I am missing?
Here are a couple photos of the latch on my freestanding cast M55 for reference. I don't see a part number in the manual, but perhaps you can contact Enviro directly or have a local metal shop fabricate it for you.

Marc
 

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  • [Hearth.com] Enviro 55M FS
    PXL_20250202_122513694.webp
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  • [Hearth.com] Enviro 55M FS
    PXL_20250202_123624864.webp
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Well, I finally had a chance to work on my Enviro M 55CFS. That link was very helpful.
Here is a little timeline of events & conditions.
  • 2:15 Powered up stove, placed on a heat level 5
  • 2:30 We had ignition
  • 2:35 #3 light came on, I pressed the on/off button, and jumped the Exhaust Temperature Switch, convection blower began to run. The temperature as measured at the Exhaust Temperature Switch was ~108 and would not climb any higher. I think that the switch closes at 140 on temperature rise and opens at ~120 on temperature fall.
  • I was reading a temperature of ~190 degrees at the outlet of the heat ex-changer tubes.
I have included a picture of the fire as well as a picture of the air closure plates inside the stove. It is like the stove is not pulling in enough air. There is no blockage of the exhaust, there is only ~8' of straight pipe. The air intake is not vented to the outdoors, but can get plenty of air inside my garage. Is there a procedure for setting the position(s) of the air closure plates? I'm getting closer!
I have included a picture of the ash pan door, I am missing a part for the latch. Does anyone have a picture or a part number for the part that I am missing?
Well, finally able to get back to this. Opened up the blower, it was clear & clean. The intake does not have any obstructions. I have left the exhaust & intake pipes off for testing. I have disconnected the igniter so that I could adjust the dampers for vacuum reading without getting burned. The vacuum blower runs, the exhaust blower runs but I do not get any reading on the Magnehelic gauge. Where should my dampers be positioned as a starting point? I have run a copper wire through the black hose going from the vacuum pump to the back of the stove and also through the red hose and the hoses were clear. Does the black hose on the vacuum pump go to the port marked in or out?Suggestions?
 

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  • [Hearth.com] Enviro 55M FS
    20250206 Enviro Inside .webp
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  • [Hearth.com] Enviro 55M FS
    20250206 Enviro Outside Test .webp
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To set up the damper start it at 50% open and follow the instructions
This unit is designed to operate within a negative pressure range of 0.15-0.17 inches of water column (37-42Pa). This can be measured using a Magnahelic pressure gauge once the unit has been running on heat level 5 setting after one hour of burn time. This adjustment is necessary for varying venting configurations. The reading can be taken from the ⅛” hole located on the right side of the Pedestal.
Watch this video
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I believe it goes to the output but I can not swear to it, It has been a while since I worked on an M55
I'll have to look it up. It may take an hour or so maybe Ssyko will come along before I find it
 
Ok im confused now, you have a vacuum blower? I am assuming that is the exhaust blower, thats what creates the vacuum in the stove. You should also have 1 silicone vacuum hose that is connected to the vacuum switch, now if you dont remember which it came off of it will be the side that the switch is on. ( if you start the stove and the auger does not move in 30 seconds try the other barbed connector)
 
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Can you post a pic of the 2 hoses you have?
 
M55
Combustion blower = exhaust
Convection blower. = room blower
Auger = turns auger shaft
Vacuum switch = controls auger/ signals control
Air Pump. = assists igniter
High limt= keeps stove from over firing
Low limit = informs control board there is fire/enough heat to run
120-140 snap disc to turn on room blower. Sometimes is controlled by low limit

Control board = controls it all🤪
 
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To set up the damper start it at 50% open and follow the instructions
This unit is designed to operate within a negative pressure range of 0.15-0.17 inches of water column (37-42Pa). This can be measured using a Magnahelic pressure gauge once the unit has been running on heat level 5 setting after one hour of burn time. This adjustment is necessary for varying venting configurations. The reading can be taken from the ⅛” hole located on the right side of the Pedestal.
Watch this video
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For more detailed information, see our cookies page.

This has been very helpful. I found the slide damper on the rear of the stove. The slide damper tab was all the way to the right (closed?). I slide it in to the mid-point with the exhaust blower running and could definitely hear the difference in air flow. I do not see any screw/fitting/hole on either sides, top or bottom of the chamber to connect the magnehelic gauge to. Does anyone have a picture of this port? Should I drill and tap a port? Also the device that I thought was a vacuum pump, was an air pump/blower to assist with the igniter. The black hose goes to the port labeled "out" on the air pump. The red hose connects to the vacuum switch. This table is very helpful. The round dampers inside the stove on either side of the fire pot were completely closed. Shouldn't they be in a partially open position? It would seem so to allow air flow through the fire box. If they should be open, what position is a good starting point? Again thanks!
M55
Combustion blower = exhaust
Convection blower. = room blower
Auger = turns auger shaft
Vacuum switch = controls auger/ signals control
Air Pump. = assists igniter
High limt= keeps stove from over firing
Low limit = informs control board there is fire/enough heat to run
120-140 snap disc to turn on room blower. Sometimes is controlled by low limit

Control board = controls it all🤪
 

Attachments

  • [Hearth.com] Enviro 55M FS
    20250207 Enviro Slide Damper .webp
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  • [Hearth.com] Enviro 55M FS
    20250206 Enviro Inside .webp
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The round (what you call dampers are covers for holes to clean out ash from behind
and firebox and should remain covering the holes except for cleaning
One of the 2 vac hoses will go to a nipple on the back of the firebox put
the gauge hose on that nipple to read vac