New Furnace Day: Drolet Heat Commander

[trx250r87]

If you're annoyed by the air leakage at the front of the Heat Commander get yourself some high temp black silicone and seal those leaks up. I did this to mine right after I installed it, thanks to advice from FixedGearFlyer.

Eric

 

[brenndatomu]

I mean next week Thursday it’s gunna be 12 and rain..

12* and rain?! You must be in Canada...12*F there ain't gonna be no rain!

 

[brenndatomu]

If you're annoyed by the air leakage at the front of the Heat Commander get yourself some high temp black silicone and seal those leaks up. I did this to mine right after I installed it, thanks to advice from FixedGearFlyer.

Eric

Wouldn't have to be HT silicone...it doesn't get that hot around the ash drawer, and HT silicone is only rated for a few more degrees than regular (50-100* more...unless buying some exotic grade stuff, then that might buy you another 50*) so even regular clear silicone caulk would work too.

 

[NSGUY]

For sure friend keep us all updated. I think you’re functioning alright but for some reason 1/3 full these stoves just don’t like it as much. I’ve yet to try a full load this season because it’s been so mild. I mean next week Thursday it’s gunna be 12 and rain..

yeah i'm thinking that with running the 1/3 loads or less and the furnace trying to get itself up to temp is whats happening coupled with not having a Manometer hooked up and knowing for sure whats going on there. but at least now I know why the furnace is doing what it is doing with a 1/3 load.

 

[NSGUY]

If you're annoyed by the air leakage at the front of the Heat Commander get yourself some high temp black silicone and seal those leaks up. I did this to mine right after I installed it, thanks to advice from FixedGearFlyer.

Eric

To me that air leak doesn't make any difference, I'm not going to worry about it at all

 

[trx250r87]

Might

To me that air leak doesn't make any difference, I'm not going to worry about it at all

Not make a difference but sometimes makes a mess of any ash on the lip or floor in front of the furnace.

The black silicone blends in well.

Eric

 

[sleewok]

For you guys that have been using your HC's for a while now, have you ever cleaned your thermocouples?
The maintenance schedule says to do it after every cord or so...between the upper and lower TC's and the RTD probe in the plenum, that's the only info the computer has to make decisions about what to do and when.
The manual says they (TC's) just need a light cleaning with a brush...upper one accessed by sliding the baffle boards forward...flyash is a pretty good insulator...I can easily see how being dirty could throw things off.
View attachment 303754

I wasn't aware of the thermocouple above the baffles! I stacked the baffles and slid them forward. Look what I found. Brushed it off and I'm curious to see what impact it has.

 

[trx250r87]

I'm on my 3rd season with my HC and my thermocouples look about the same as yours. I was not experiencing anything abnormal but figured I would give them a quick inspection.
I knocked off the fine ash powder with a plastic brush and they look as good as new.

Eric

 

[sleewok]

Question: would a fresh air intake impact the rate of burn?

I was checking the dampers and took off the panel blocking the air intake on the opposite side of my outside air connection. I noticed a cool breeze blowing. This got me thinking. If the box with the dampers is closed off with only fresh air intake, would the pressure of the air force more air into the chamber and cause it to burn hotter/faster? That seems to make sense to me. I am going to leave the cap off to see the impact. If I notice one I'll probably put a damper on my air intake.

 

[sleewok]

Could some of you check your dampers to see how tight they are against the back of the box? I think I may have found another issue with mine. The damper on the left (when standing in front) is about 1/4" offset from the box. That means there is always a large gap, regardless of how closed it is. The damper on the opposite side is much tighter to the box. I'm going to give Droplet a call tomorrow to find out what the gap should be.

 

[trx250r87]

They both should be tight. Check to see if the set screw has backed out.

Eric

 

[brenndatomu]

There should be no gap....against but not rubbing

 

[sleewok]

There should be no gap....against but not rubbing

2 screw for each damper we're sitting under the dampers when I opened it up. One screw is missing. The dampers are very loose. It is pretty frustrating to find this the case. Now I have to completely remove the damper assembly to get those screws in.

But also glad that I have likely found the cause of my high burns.



After further inspection it appears that I have a defective damper. The screw slot? for the bolt on the left damper overlaps the opening. This blocks the damper and never allows it to fully close. That means the damper is always 1/2" open, even when fully closed... Seriously!?

 

[sleewok]

Update:
I spoke with Martin over at SBI today and they have me setup for a damper assembly replacement. The placement of the standoffs should be the same on both dampers and my primary is clearly offset from the intended location.

Since that conversation I ground down the standoff so that the primary damper can close down to about 1/4 in gap (vs 1/2 before).
I remounted the steppers and then checked that the dampers are flush to the box. All good.
Fired it up.

The difference is HUGE. It is operating the way I would have expected. When there is no call for it the only flame I see is secondary burn. The blower turns on significantly less as well. I'm so glad I figured this out. I'll post back how it does with an overnight burn after these fixes.

PSA: Those of you that have been having your blower constantly turning on during idle you NEED to check your dampers and make sure that they are operating correctly. Hopefully no one else has to face this issue, but at least the potential for it is known.

A couple other things that I learned about the operation of the HC.

Plenum Pressure
The manual states to get the plenum pressure to 0.2. The actual range is 0.2 - 0.5. IF your pressure is below 0.2 then the thermocouple in the plenum will have a tougher time accurately reading the temperature

Plenum Temps
The blower is triggered by the plenum temperature. Their are two separate temperatures that will trigger the blower.
1) When calling for heat the blower will turn on when the plenum is @130F
2) When no call for heat, it will turn on the blower when the plenum is @190F

Cheers,

Lee

 

[trx250r87]

A little Loc Tite wouldn't hurt on those threads so they do not come loose again.

 

[sleewok]

Update: after my fixes I would guess that I'm using about half the wood I used previously. The temperature is more consistent. Previously it would reach 5+ over my set point. Now I can throw a few logs on the coals and it will continue to hold my house temp for a few more hours. Previously I would have to do full loads each time. Now I just need to get automated zoning for my dampers!

 

[sleewok]

I received the replacement damper assembly. It is slightly different from my original. There is a plastic piece on the damper that I assume is to reduce friction.

The standoff for the "P" damper is still positioned inside the cutout. I reached out to SBI again to verify if this is the actual position as engineered. I'm waiting to hear back.

Would someone be willing to open up their HC and check the position of that standoff?

 

[3650]

Wow seems like burning wood shouldn’t have to be this complex.

 

[brenndatomu]

Wow seems like burning wood shouldn’t have to be this complex.

It actually does... EPA said so...

 

[trx250r87]

I received the replacement damper assembly. It is slightly different from my original. There is a plastic piece on the damper that I assume is to reduce friction.

The standoff for the "P" damper is still positioned inside the cutout. I reached out to SBI again to verify if this is the actual position as engineered. I'm waiting to hear back.

Would someone be willing to open up their HC and check the position of that standoff?

View attachment 305585 View attachment 305586 View attachment 305587

Looks like SBI updated the material of the dampers! Mine are just made of steel and they chatter when opened/closed.

I have the back of my HC removed so I can snap a pic of mine but I not sure what standoff you are talking about.


Eric

 

[sleewok]

Looks like SBI updated the material of the dampers! Mine are just made of steel and they chatter when opened/closed.

I have the back of my HC removed so I can snap a pic of mine but I not sure what standoff you are talking about.


Eric

If you take a photo at an angle like my 3rd photo showing the "P" damper then it should be visible. In my photo it is one of the metal posts that the motor plate is mounted to (the one right above the limit switch).

 

[trx250r87]

If you take a photo at an angle like my 3rd photo showing the "P" damper then it should be visible. In my photo it is one of the metal posts that the motor plate is mounted to (the one right above the limit switch).

Does this help?

 

[sleewok]

Does this help?

View attachment 305631

Need the shot lower so that we can see the cutout in relation to that lower mount in your photo. In my damper assembly that lower mount is overlapping the cutout so the damper can never full close. This might be by design, but I am not sure. Can you try a photo with the dampers fully closed (pull the plug). Thanks for sending this regardless!

 

[trx250r87]

Need the shot lower so that we can see the cutout in relation to that lower mount in your photo. In my damper assembly that lower mount is overlapping the cutout so the damper can never full close. This might be by design, but I am not sure. Can you try a photo with the dampers fully closed (pull the plug). Thanks for sending this regardless!

 

[sleewok]

View attachment 305691

it looks like yours is mounted in the same position, slightly overlapping the opening. this might really be by design. It seems like an odd decision to me since there is no way for the dampers to full close in an emergency. I'm sure SBI has a good reason for it though. Perhaps something to do with gas leaking into the home if it is fully shut with a fire still going. Just a guess...