Inconsistent water temp

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Kevin5516

New Member
Dec 4, 2018
2
Pennsylvania
Hello,

One month ago we installed a heatmaster c250 and all is working great for the most part. 90% of the time the temp on aquastat stays within settings (160-170). This morning I went out and it was at 130. This has happened a number of times. The blower is on and eventually it gets back up to normal temp. I figured it was due to not enough heat calls so I adjusted the timer to turn the blower on for 1 minute every 1/2 hour. It seemed to help a little but still having the same issue. I also cleaned all baffles, chimney and ash pan.

Is there something else I should look at?

Thanks in advance for any info.

Additional info:

heatmaster C250
pumped into heat exchanger into oil boiler
1500 sq ft old uninsulated farm house + DHW
 
I'm no expert, and don't even have an outdoor boiler.
But...are you saying you're not getting consistent overnight burns? Is it loaded enough?
The unit seems big enough where you should.
If it's been that way because it's hasn't been that cold out, could the wood be too green? I realize these units probably are meant to burn pretty green wood, but is there such a thing as too green?
 
Hello,

One month ago we installed a heatmaster c250 and all is working great for the most part. 90% of the time the temp on aquastat stays within settings (160-170). This morning I went out and it was at 130. This has happened a number of times. The blower is on and eventually it gets back up to normal temp. I figured it was due to not enough heat calls so I adjusted the timer to turn the blower on for 1 minute every 1/2 hour. It seemed to help a little but still having the same issue. I also cleaned all baffles, chimney and ash pan.

Is there something else I should look at?

Thanks in advance for any info.

Additional info:

heatmaster C250
pumped into heat exchanger into oil boiler
1500 sq ft old uninsulated farm house + DHW

Not sure I'm understanding fully, but that would usually be because the fire went out or it was out of wood or you were pulling more heat off it than it could maintain.

What kind of heating system is it tied to? Does it have return temperature protection?

EDIT: I see you partly answer part of that already. HX to oil boiler.
 
I have noticed it happening randomly during the day. It has always come back up to temp but can take some time. This morning for example, when i opened the door there were 2 pretty big chunks (16" round) still in the bottom and the temp was at 130 and the blower was on. Eventually it came back up to 170. The unit is set at 170 with a 10 diff. The wood I'm burning now is mostly oak rounds and i checked the MC to be 36%. Maybe I need to keep it more stuffed with wood, but it seemed to me to burn smaller fires would be best so filling it 1/2 to 3/4 full in milder weather filling twice a day. I don't think I'm pulling too much heat off of it, I actually don't have the domestic hot water loop pump running so right now its just heating the radiators in the house.

No return temperature protection.

Hopefully that helps clarify, this is all new to me...

Thanks!
 
36%...…………...Really, that's what you burn?
 
36% moisture is really pretty green still. Especially for oak. But if it's been warmer days you will be idling the burn more often and if it idles long enough it will get to a point where the fire goes out and then the combustion fan kicks on. If there's no fire to make great while the combustion fan is running it basically blows cold air through the fire box and it the chimney. This cold air will dramatically drop the temps in the water jacket over a night's time.

Try burning wood with a moisture closer to 20% it will coal up better and help keep your fire going. Also if possible on warmer days do smaller fires and wait until later in the evening to start the over night fire.
 
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Kevin, although this is an excellent forum, there is a forum with more members who have experience with the same unit that you have. Not so many here. You will find it here. Best of luck in your heating needs.
 
Until you get a chance to try some drier wood you could split what you have smaller to help it dry out faster. You may have to load it heavier than is ideal to let the wood on top dry out before it gets down to the grates.
It should keep up with any heat load under 200,000 btu's /hr with the right fuel.
Keep us posted!