Looking for input on Thermo-Control boilers

[rwh442]

I bought it in 2008 from Alternative Heating Solutions in Herkimer, NY. The price would have been the same from Thermo-Control so take your pick. AHS had other boilers at the time I was looking like the Econoburn so after talking with them I bought the Thermo-Control through them.

I went to Thermo-Control's website and it does say "for commercial use only". That is recent within a few months I would estimate, I don't recall it being there last time I checked. I think I recall some new EPA clean air boiler law that came into effect, probably this year.

Tell them you have a large greenhouse out back. LOL.

 

[mpilihp]

I bought it in 2008 from Alternative Heating Solutions in Herkimer, NY. The price would have been the same from Thermo-Control so take your pick. AHS had other boilers at the time I was looking like the Econoburn so after talking with them I bought the Thermo-Control through them.

I went to Thermo-Control's website and it does say "for commercial use only". That is recent within a few months I would estimate, I don't recall it being there last time I checked. I think I recall some new EPA clean air boiler law that came into effect, probably this year.

Tell them you have a large greenhouse out back. LOL.

Hello again, I've found they can no longer sell new units to residential customers but a local dealer has some lightly used units they could sell me. I'm curious if you have an insulated or not insulated unit and how much heat it puts off as radiant heat. Reason ours is in the basement and we burn year round to hear our DHW and a hot tub. I don't want it to drive us out in the summer..

Thanks

Phil

 

[rwh442]

My boiler is uninsulated in a 1600 sq ft detached garage with three roll up doors. The garage itself is insulated and the garage doors are "insulated" also. I rarely see the garage temperature get below 60 degrees F in the dead of winter. If you had one of these uninsulated boilers in your basement, running in the summer, you could probably not stand to be in the house. Insulating the boiler would help some but there is a LOT of heat coming off the front loading door and stack. Probably not recommened for summer use.

 

[mpilihp]

My boiler is uninsulated in a 1600 sq ft detached garage with three roll up doors. The garage itself is insulated and the garage doors are "insulated" also. I rarely see the garage temperature get below 60 degrees F in the dead of winter. If you had one of these uninsulated boilers in your basement, running in the summer, you could probably not stand to be in the house. Insulating the boiler would help some but there is a LOT of heat coming off the front loading door and stack. Probably not recommened for summer use.

Hi thanks for the in. My current boiler the front is not insulated though its smaller area. But the new unit is much taller and pipe comes out of top so will need much less pipe and a lot heat come off of that now so maybe it will b a wash.

I've committed to buying it, waiting to hear when it arrives for pickup.

Phil

 

[mpilihp]

So I finally got the plumber over to help pipe the new thermocontrol boiler into my system this week. I got the controls hooked up tonight and fired it up. Initial observations:

The thermo switch for the stack trips the draft door closed way too early, about 325 deg.

Unit appears to be air starved. Only way to get it to run the stack hotter than 300 with the baffle in normal operating position is to Crack the door open. Even with it in bypass it only gets to about 325-350.

Takes a LONG time to get up to temp and start circulating. 2hrs!

I think the draft intake is too small. My 70k btu log wood boilers draft opening was 3 times as large.....

Gonna let it run on its own now and sleep on it.

Phil

Sent from my SM-G900R4 using Tapatalk

 

[rwh442]

Do not run with the door cracked, you would have no control. It could overheat in minutes.

In August I would probably have the same problem with mine, no draft on the stack. Temperature differential between inside/outside is probably almost zero.

Once you get near winter and if you still have the same problems I would shim out the stack limit switch with washers. Right now I probably wouldn't touch it.

 

[mpilihp]

Do not run with the door cracked, you would have no control. It could overheat in minutes.

In August I would probably have the same problem with mine, no draft on the stack. Temperature differential between inside/outside is probably almost zero.

Once you get near winter and if you still have the same problems I would shim out the stack limit switch with washers. Right now I probably wouldn't touch it.

Hi I was with it the whole time monitoring it, I closed the door when I left it. Was doing that to troubleshoot IE figure out the issue.

Waiting till fall isn't an option as I burn year round to heat our DHW and hot tub. My old 70k btu boiler I just removed had no issues like this. Seams the intake is too small. I'll shim out the stake limit switch and see if that resolves that issue but the air supply issue is a problem for me, we like taking hot showers...

 

[maple1]

I don't think it is an air supply issue - more likely a draft issue, as suggested. This time of year, chimney draft will be quite diminished. Your old unit may have had differing draft requirements, that allowed it to function a bit better with lower draft. Have you checked your draft with a manometer? I see the manual specs 0.05-0.08" - so that is likely what the air supply is tuned for.

But your main complaint with your old one, reading back, was big frequent creosote buildup. So the old one likely wasn't quite a 'no issues' setup either.

 

[mpilihp]

I don't think it is an air supply issue - more likely a draft issue, as suggested. This time of year, chimney draft will be quite diminished. Your old unit may have had differing draft requirements, that allowed it to function a bit better with lower draft. Have you checked your draft with a manometer? I see the manual specs 0.05-0.08" - so that is likely what the air supply is tuned for.

But your main complaint with your old one, reading back, was big frequent creosote buildup. So the old one likely wasn't quite a 'no issues' setup either.

Hi yes the wood boiler I removed generated a lot of creosote but it was capable of running hot, it easily would run up the stack pipe temp as the bi metal draft control was slow to react. The desire/hope of upgrading to this Thermo-Control unit was to be safer to run ( better temp control and hopefully less creosote generated) have better heat ability for overnight burns and extreme cold. Old unit was only 70K and could not go all night without a 1 am filling and could not keep house warm when sub-zero nights.

So I am far from knowledgeable on wood burning/draft needs. Can you tell me why then if I crack the door open it will burn hotter?

Both of these are not gassers and I know even this one will generate creosote, im hoping it creates less. But a low burn temp is not going to improve that situation.

~ Phil

 

[maple1]

So I am far from knowledgeable on wood burning/draft needs. Can you tell me why then if I crack the door open it will burn hotter?

~ Phil

I'm far from an expert too, but I would suspect opening the door is just compensating for the low draft conditions that the intake is not tuned for. And also would suspect that if you ran with the door open under optimal draft conditions, you would likely get into an overburn or too hot flue temps situation.

Have you asked the dealer or Thermo Control people for some input? Might help, likely they get similar questions on initial setup issues from others.

 

[mpilihp]

I'm far from an expert too, but I would suspect opening the door is just compensating for the low draft conditions that the intake is not tuned for. And also would suspect that if you ran with the door open under optimal draft conditions, you would likely get into an overburn or too hot flue temps situation.

Have you asked the dealer or Thermo Control people for some input? Might help, likely they get similar questions on initial setup issues from others.

I spoke with them before purchasing it and I knew going into it I have a smaller than preferred flue 6" instead of 8". I do need to call them but havent had a chance, I want to do more tinkering/learning before I call so I have some experience with it and can answer their questions.

The chimney was existing and isnt going to change, I needed to make a change with the logwood as it does not have enough capacity and Ive been concerned about safety. Plus the threaded connection at the output has started to leak and I would have needed to drain and repair that so I figured it was time to try upgrading.

Interesting item as well, before I installed this, the flue port on the chimney had not had not been fully opened so it was more of a 5inch hole into the chimney instead of 6 in (estimating) I took a diamond cutter to it when I had the boiler out for the swap and opened it fully up. I was hoping that would improve the draft, maybe it did...

~ Phil

 

[maple1]

Not sure what 'logwood' is?

How tall is your chimney?

 

[rwh442]

My stack limit switch was shutting mine dine at lower stack temps also when I first installed it so I had to shim it out. I think it trips now around 650 F. I run the stack at a controlled 600F like I discussed with you before so my stack limit is essentially a backup - it never gets there unless I test it like I do every year but bumping up the stack temp control.

On warmer days mine acts like yours too - I just don't think you have enough draft now with the warmer temps outside. The 6" stack probably isn't helping much either.

Looks like we are having a "cold spell" here this weekend - 80's during the day and mid 50's at night. Eliminate the stack limit switch for now, watch the stack temps, burn dry wood on one of these cooler nights (if you get them) and see how it acts then.

 

[mpilihp]

Not sure what 'logwood' is?

How tall is your chimney?

Hi the logwood is a older water jacket boiler, I think it holds 50 gallons if my memory serves me at all. We have a 1 1/2 story cape and the boiler is in the basement so its going through three full stories and the roof area so 38 ft I'm guessing.

 

[mpilihp]

My stack limit switch was shutting mine dine at lower stack temps also when I first installed it so I had to shim it out. I think it trips now around 650 F. I run the stack at a controlled 600F like I discussed with you before so my stack limit is essentially a backup - it never gets there unless I test it like I do every year but bumping up the stack temp control.

On warmer days mine acts like yours too - I just don't think you have enough draft now with the warmer temps outside. The 6" stack probably isn't helping much either.

Looks like we are having a "cold spell" here this weekend - 80's during the day and mid 50's at night. Eliminate the stack limit switch for now, watch the stack temps, burn dry wood on one of these cooler nights (if you get them) and see how it acts then.

Hi so an update on my progress, I shimmed the limit switch out about 3 times as far as is suggested and as you said we had a cold night last night so I fired it up. I also discovered the unit has some draft tubes that are low and on both sides of the door and bring air out to the back of the firebox for its 'second burn' area. I first fired it up and wasn't making a good draft, running around 300 deg. I blocked both of those tubes off and it did make a difference on the draft through the door, I could hear it flowing through the entrance. The stack pipe temp rose a lot, the stack limit switch shut it down at about 450 deg, still too low so Ill shim it out even more. I removed the blocks on the draft tubes and it continued to run at about 400-450 with the limit switch removed. I have a damper in the pipe and I did have to close it down some at one point because it started to race over 650 deg.

One new issue I did not like is this situation. So the boiler temp go up over 184 and caused the aqustat to open and shut the draft door which is correct. BUT once the boiler temp went back down low enough to open the draft door it belched a lot of smoke out and it made a loud noise, I'm guessing it was starved for air and when it got the air, it exploded in fire causing it to spit smoke out. Do you have this happen?

I think it will be fine for the winter but I do not think I will be able to continue to heat my DHW and hot tub with the boiler during the summer. Mainly because of the amount of wood it takes to get it hot and start heating....

~ PHil

 

[maple1]

Where are you measuring those temps, and what with?

 

[mpilihp]

Where are you measuring those temps, and what with?

Hi on the stack pipe about 1 foot from the stove with two different spring type thermometers. I know they are not the most accurate but its what I have. I have a PID and thermo-coupler probe on order and plan to move to using that to control the draft door when I figure it out and get it working.

 

[rwh442]

I have a type K thermocouple probe sticking in my stack about 1.5 - 2' up to measure my stack temps.

Did you have the two secondary burn tubes blocked when the stove "belched" when the draft control opened on the door? Those tubes need to be open at all times. During your idle period (over 184 deg F) when the draft door control is closed there is still a little bit of air being drawn into those tubes so your fire doesn't completely smother. It is not enough air intake to keep the fire burning hot but enough to keep it from completely smothering.

The only other time I had mine "belch" is when I didn't pay attention to the temperature (it was in idle mode, draft control on the door closed) and I opened up the door . . . burnt some hair off the front of head. Kids and wife laughed their #%! off. My damper control on the front door opens slowly - maybe in about 4-5 seconds? Mine never belches like you describe when the draft control is opening up after ide.

 

[maple1]

Hi on the stack pipe about 1 foot from the stove with two different spring type thermometers. I know they are not the most accurate but its what I have. I have a PID and thermo-coupler probe on order and plan to move to using that to control the draft door when I figure it out and get it working.

It is a LOT hotter inside the pipe, than what spring type thermometers say. Mine reads 100c less that what a probe thermometer says right beside it, when I'm burning. I.e., when the spring says 400f, it's really 575f in the pipe.

I would hazard a guess that 650f on one of those is overfiring, by a fair amount.

 

[mpilihp]

Hi so I would think that 99% of the wood burning users do not have a digital stack temp monitor and go by a similar spring gauge. I'm sure it is hotter but Ive always run by these (I use two to validate them) and is a good gauge. My two concerns are to be burning hot enough to prevent heavy creosote buildup and to know when the temp is racing away (over temping). I plan to add a PID on the stack to have an accurate temp and cutoff of the intake door and also a second PID on the boiler jacket temp with a Honeywell variable stepper motor control to variably control the air intake to slow it down when the water is getting too hot so it will regulate without doing a hard off/on all the time for temp control.

 

[maple1]

I may stand to be corrected some, if your spring thermometer is a probe type rather than a magnetic type. Mine is a magnetic.

 

[mpilihp]

I may stand to be corrected some, if your spring thermometer is a probe type rather than a magnetic type. Mine is a magnetic.

No its magnetic, just they have been the norm/standard for most wood stove users over the years.

I may have mis spoke. I have a PID with a thermo couple probe on order to replace the stack switch and magnetic temp gauge but could take me a while to figure out and get working. Last PID I had took me a long time to figure out how to get working, then it lost its memory and I couldnt get it programmed correctly again years later....

 

[rwh442]

Phil,

I wouldn't mess with the stack limit switch shimming until you get an internal, accurate stack temp with your thermocouple. I have mine sticking in about 3" into the stack. The externals do read lower from what I read, no experience with them though.

I played around with stack temp control limits for months - started with 400, 450, 500, 600 etc etc. I personally found 600 to burn the best. The lower temps resulted in slower burns, more creosote. Above 600 I didn't find any benefits and the wood just burned quicker.

 

[mpilihp]

Phil,

I wouldn't mess with the stack limit switch shimming until you get an internal, accurate stack temp with your thermocouple. I have mine sticking in about 3" into the stack. The externals do read lower from what I read, no experience with them though.

I played around with stack temp control limits for months - started with 400, 450, 500, 600 etc etc. I personally found 600 to burn the best. The lower temps resulted in slower burns, more creosote. Above 600 I didn't find any benefits and the wood just burned quicker.

Well at its default setting it was shutting off before 300 by the magnetic temp gauge. Last setting was a t 450 which could mean it is shutting off at 550 based on what maple1 indicated the difference was. I would rather have it shut off at about 650, a bit higher than 600 so that after it does shut off and comes back on it is in the more optimum temp range. I forget now at what temp it turned back on it when it was at 450, should have written it down.

I'm currently trying to finish a project car so may not get to the PID setup right off. I do have a smaller stove pipe to try as I read you should go immediately to the smallest size from the appliance that would be needed in the connection to the chimney. I currently have 8in from the boiler to the chimney with a reducer to 7 in which is the connection into the chimney. If I can fit it with the reducer out of the boiler I will give that a try to see if that improves draft.

 

[mpilihp]

So I got a PID for ON/OFF control of the draft door based on flue temp. I have it hooked up and displaying the flue temp but I have no idea how to configure it, way too complicated for someone that has never done it before. The directions simply state what the onscreen cryptic description is for and the range allowed. No how to's or example configs of it.

Can anyone direct me to a how to on general PID configuration setup?

Thanks

~ Phil