Vapor fire 100 trouble keeping up in the cold

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No they wouldn’t be plugged. My wife makes sure we change them about every few weeks bc she thinks it will help with the dust. Hasn’t helped much though lol.
 
I did switch to a little higher merv rating filter just bc they were substantially cheaper in a 3 pack at Lowe’s. You think I need to go back to the lower merv they recommend? Which I used the recommended earlier and it still struggled to keep the house heated.
 
I run a merv 5 IIRC...stock is 3. I doubt it would make a big difference in your case...unless you have something much higher in it.
 
I looked and mine is a merv 8. They call for a merv 5. I am going to turn the t stat off and see what it does. I will switch the filters if I don’t see any change
 
They call for a merv 5.
Hmm, musta changed it...I have 5's in now and I know that was a step higher than the Purolator filters it came with.
I doubt merv 8 would cause your issue, but could be a contributing factor...?
 
Extended cold snaps are tough. Heat loss is exponential.
That's true...we usually don't get as cold as y'all, or as long, but I have noticed that the house 24 hr average temp is a factor when dealing with real cold temps.
This cold snap this year is the longest and coldest since I've had the Kuuma and I usually load medium sized loads 3X day during real cold weather, but tried large loads of dense wood (like oak n locust) and went to 2X day this year...that worked pretty well too. I did have a couple times where I needed to burn down a large pile of coals before reloading, so I raked them forward and put like 6-8 lbs of half punky oak sapwood splits on it too...raised plenum temps 15* and didn't really add to the coal pile...loaded a full load an hour or two later...might hold the current house temp, might raise it just a bit...but the main thing is that 24 hr average indoor temp...if ya can keep it from dipping, you'll be fine, but once it does, takes a lot more heat to get back to your preferred temp, unless outdoor temps jump up a good bit.
No shame in bumping the fossil fuel furnace on for a bit to supplement, if needed.
We have a stove in the LR fireplace, so I can light that too if I get behind... that'll flat out run you outta the house if running both at the same time! Of course if it gets too hot, the Mrs starts taking layers off, so... ::-)
 
That's true...we usually don't get as cold as y'all, or as long, but I have noticed that the house 24 hr average temp is a factor when dealing with real cold temps.
This cold snap this year is the longest and coldest since I've had the Kuuma and I usually load medium sized loads 3X day during real cold weather, but tried large loads of dense wood (like oak n locust) and went to 2X day this year...that worked pretty well too. I did have a couple times where I needed to burn down a large pile of coals before reloading, so I raked them forward and put like 6-8 lbs of half punky oak sapwood splits on it too...raised plenum temps 15* and didn't really add to the coal pile...loaded a full load an hour or two later...might hold the current house temp, might raise it just a bit...but the main thing is that 24 hr average indoor temp...if ya can keep it from dipping, you'll be fine, but once it does, takes a lot more heat to get back to your preferred temp, unless outdoor temps jump up a good bit.
No shame in bumping the fossil fuel furnace on for a bit to supplement, if needed.
We have a stove in the LR fireplace, so I can light that too if I get behind... that'll flat out run you outta the house if running both at the same time! Of course if it gets too hot, the Mrs starts taking layers off, so... ::-)
That was the best read on the internet today. My problem has been the opposite. The Mrs. Here has been going to bed in coveralls lol
 
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I'd just load less wood vs blowing more BTU's out the chimney.
That was with 3 small pieces on when over 30f outside . house was hitting 80's . taking them out didn't really help either it was still to hot after. we just open a window a live with it. it hasn't seemed to have a huge effect on our burn times during this 50 days of single digits loads keeps up just fine.
 
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That was with 3 small pieces on when over 30f outside . house was hitting 80's . taking them out didn't really help either it was still to hot after. we just open a window a live with it. it hasn't seemed to have a huge effect on our burn times during this 50 days of single digits loads keeps up just fine.

I'm not sure what situation is worse, overheating the house the majority of time outside of when it gets abnormally cold or mine where it's perfect in normal temps but is not quite enough during that one week a winter where we see well below zero temps (70 -80 HDD's). LOL

It would be nice if we had a more efficient house though!
 
.raised plenum temps 15*

If I let our plenum temps drop 15° in real cold weather, I'm screwed! ;lol I don't like them to drop more than 5° or so from max when it's below zero outside. It's not possible when doing overnight burns.

if ya can keep it from dipping, you'll be fine, but once it does, takes a lot more heat to get back to your preferred temp, unless outdoor temps jump up a good bit.
yep, once the snowball effect starts (house temps drops, which drops the return air temp which drops the supply temp which causes the house temp to drop more.....), it's hard to reverse.

No shame in bumping the fossil fuel furnace on for a bit to supplement, if needed.

We ended up using $16 in LP over the almost two weeks of below zero temps to help boost the wood furnace. Luckily, I have them both setup so they can run and "dance" with each other at the same time. So we just set the LP stat to where we want the house temp to be and the controls setup lets the LP kick in when it needs to to keep the house at that temp. The nice thing about having the wood furnace going is that it keeps the ducts nice and warm, so when the LP kicks in we instantly get a big blast of warm air from both of them.
 
I cleaned my heat exchanger last night the best I could. Not a great setup if it is still fairly hot. I turned off my t stat so it would just blow on low. My stack temps only got to 475 before it lowered as it started cycling down to the c setting. It did lower my stack temps there. I think my stack temps are still fairly high now though as they stay in the 350 to 370 range as it is running in the 1 and c setting. But maybe that is still normal. I do think it helped with the heat though as it maintained the house temp all night. The past week or so it would drop a few degrees at best during the night as it would die down.

I cleaned the Mano tube on both ends. When I first loaded last night my reading was -.03. When I went down this morning it was at .12 at the end of the burn. Again it is in my basement. When I loaded this morning it went down to around .07, so I moved the bar from like 2 to around 4 and it dropped it down to .04. I had ran my Baro last year on around 4 and was getting high temp alarms frequently and dale said to lower it a bit and it should help with the high alarms. This Mano reading still has me stumped. But I do think I am making headway heating the house with the t stat off. I will see what it is when I get home from work today
 
Where does the other tube on the Dwyer go? It should just be atmosphere...heck just take it off the meter.
 
My stack temps only got to 475 before it lowered as it started cycling down to the c setting. It did lower my stack temps there. I think my stack temps are still fairly high now though as they stay in the 350 to 370 range as it is running in the 1 and c setting.
Still sounds high to me...when the HX is clean, and I'm running with computer on low (99% of the time) stack temps get to about 425* with a fresh load, and still on 3, then hangs out around 300-325* on pilot (c) it gets under 300* occasionally too.
That's with baro set so that Dwyer is reading -0.04"...and it varies very little...might hit 0.05", or maybe 0.06" with a wind gust.
I'd have to hook the shop vac up to it to get it near 0.10!
With my chimney that means the sliding weight on the baro is set to about the 2 mark (close to the whole way out)
 
I do have my computer cranked up right now. You think I need to back it off?

Also, I should be getting a negative number (to the left of the zero mark on the Mano) with the initial load? It did that this morning. But then it will go back across the zero and near a positive .1
 
I do have my computer cranked up right now. You think I need to back it off?

I just think with your quick cleaning in a warm firebox you probably didn't get it good and clean. It's not going to hurt anything, just won't be as efficient.

Also, I should be getting a negative number (to the left of the zero mark on the Mano) with the initial load? It did that this morning. But then it will go back across the zero and near a positive .1
That is just plain weird. Negative, with the way you have it hooked up, means positive pressure. Was their smoke being pushed out of the Kuuma when it was like this?
 
No smoke being pushed out of the stove. I do have my end of the mano inside the collar of the stove and inside of the stove pipe. I don’t know if that is too close to the stove. I just did that and it doubles as a screw to hold the pipe in place.
 
I did notice that the draft sample is being taken right at the firebox...never known anyone to take it anywhere other than the pipe...maybe that makes a difference, not sure?
But you said it was fine before, right?

What temp is your basement? Are the return ducts really cold?
We had a guy here a couple years ago that put one in his attached garage, and had some janky diy ducts to the house...he was mad cuz it wasn't making heat. Told him to insulate the ducts, but he got mad n sold the Kuuma, replacing it with some cheapo furnace...he came back a year later and admitted selling the Kuuma was a big mistake.
Anyways, really cold return air temps knock the crap outta the supply duct temps!
 
It is inside the pipe but right where it connects into the collar.

Basement temps are about 62 or 63. The ducts are insulated so I don’t think my return air is that cold.
 
Yeah I think my stack temps are running higher than they did last year. Maybe a really good cleaning will help it out.

When you say you are running your baro on 2 which means almost the whole way out, you are meaning it is almost all the way to the middle correct? From the middle going to the right, mine goes from 2 to like 8 from left to right.

That dang Mano has me throwing in the towel. I came home this evening needing to reload. My mano was right at 0.12. I unhooked the little part that was dangling and free to the atmosphere. I unhooked the other side to make sure it was showing zero and it was. I hooked it back up and reloaded and was getting a negative -.02. Just not sure how it would fluctuate that much.
 
The Mano reading is still all over the place. I haven’t changed it to up higher in the pipe yet so I am hoping that will help. It will be up to .20 and then I can unhook it and hook it back up and it will go down to a negative reading, but then way up high again at the end of the burn.

It hasn’t been as cold, but it seems like it has done better with the thermostat unhooked.
 
Been mulling this over in my mind...just can't understand how this can be happening...that Dwyer is just so dead simple that I don't see how it can be malfunctioning...but, I wonder the results if you find it abnormally high again, unplug it so it goes to zero, then plug it back in to see if it reads a more expected number, then if it does, switch the hose over to the left port, see if it reads the same on both sides of zero.
The only thing I can think of as far as the meter screwing up would be if there is an air bubble in the oil reservoir that is fouling things up sometimes...but I know that seems unlikely...
 
Have you checked that the manometer tubing isn't clogged with crud...
 
I am going to take it apart and make sure it is all clear and also try to make sure there isn’t any bubbles in the fluid. It has me baffled.
 
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