Expected temperature

Foxy24 · Post by **Foxy24** » Sat. Jan. 19, 2019 1:52 pm

Hello all,
I'm new to coal heating and this forum so please take it easy on me if I'm not using the correct terminology/ posting in the incorrect category. I'll give you some background info, I bought a used keystoker 90000btu unit, I've never heated with coal before,I grew up burning wood but I just recently moved out and the house I bought had a heat pump. I got tired of paying the electric bill so I decided to go with coal and run my heat right into my existing ductwork and just have the circulating fan help push the hot air around. I have a powervent running through my block wall, a barometric dampner and a permanent manometer as recommend from many on the site. This forum has been a lifesaver for all the questions I've had so far but I have a few myself that I did not see answered yet. What temperature air can I expect to be pushing out the "fresh air" portion of my stove and what should my exhaust temps be? I know if I have my draft set too high I'll be pulling more heat out of the stove than needed, but if I have it set correctly at .03 ish what exhaust temps can I expect? And if I have my stove at full burn, with my thermostat not satisfied and my combustion blower totally open, what temps can I expect out the front? A consistent 180? I'm just guessing I haven't measured yet but mine just seems to be low. I ahve done all the preventative maintenance that I could find already, cleaned all blower units,pulled my grates up and vacuumed fines out and recemented, checked to ensure correct stroke of the stoker system and that the thermostat is commanding it on. Everything seems to be working like a champ but just didn't seem like very hot air coming out of my registers around the house. I'm trying to heat a 2500 sqft house Wich I know is large for the stove size but it seems that others have heated the same if not larger with no problem? Maybe im expecting to much. Any and all suggestions/feedback would be much appreciated!

RFK · Post by **RFK** » Sun. Jan. 20, 2019 11:19 pm

It sounds like you have everything set up about right. What actual room temperatures are you seeing? That's the important factor. I have no experience with a Keystoker. My Harman Mag Stoker is rated at about 85,000 BTU. It is dispersing the hot air directly into the room. I do not have it hooked up to ductwork. I rely on natural convection to circulate the heat. Downstairs stays pretty comfortable, upstairs is ok but cool. Right now I only have 8*F outside here with some wind. Stove is working hard and mostly running full out with only limited maintenance cycles. I am holding 68* in the room adjacent to the stove where the thermostat is located. I never tested the temperature of the air coming out of the stove, but it is pretty hot, i'm sure well over 120*. Near the end of a heat cycle you don't want to leave your hand in the hot air stream very long. At that time my stove side temp. will usually be between 500 and 600. My stack temp above the baro never exceeds 190*. Draft is running around -.05 to -.06 right now with the cold and wind. Draft at idle is usually about -.03 to -.035 unless the wind is blowing. Maybe someone with Keystoker experience will chime in.
Rick

titleist1 · Post by **titleist1** » Mon. Jan. 21, 2019 7:46 am

I have the same set up as RFK, Mag stoker, free standing, no duct work, my stove and flue temps are similar to his. I know the temps get over 120 on the air coming out the front. I put a regular outdoor thermometer in front of the air flow coming off the stoker one time to see what the temps were and it max'ed out the temp and melted/deformed the plastic housing around the glass bulb!

What are your temps on the stove sides and flue pipe?

You are probably losing heat off the ductwork and that is the reason for the cool air coming out of the registers. I tried connecting ours to the ductwork in our house. I had good temps at the three registers closest to the stove but on the long run to the back rooms there was room temp air coming out the registers. I went back to the free standing set up.

Trial and error air circulation moves the heat adequately around the house for our climate 95% of the time. This morning at 10* and windy is one of the 5% and the furnace is kicking on once in a while which I expected. The stoker ran all but 20 minutes from 11:30 last night to 7 this morning as my 'timer' read 7 hrs 10 min.

RFK · Post by **RFK** » Mon. Jan. 21, 2019 11:17 am

Yeah, It's unusually cold for my area . Not sure how cold it got last night but I only had 7* at 9:00 this morning and it's breezy. Stove is running constantly now. I only have 64* in adjacent room where thermostat is located. Stat. is not being satisfied set at 68. Burned about a 5 gal. bucket of rice between 8:30 pm last night and 9:00 this morning. It's only supposed to go up to 16* today and back down to 3* tonight. Hope everyone is staying warm!

Title, not to highjack, but what JD do you have? I had 2 JD 2-cylinders for years.
Rick

k-2 · Post by **k-2** » Mon. Jan. 21, 2019 1:39 pm

My keystoker K-2 Boiler only nets 76000 BTUs but im heating 3000SF to 78 degrees today while it 12 degree outside.
My house is about 100 yrs old and somewhat insulated although not even close to code.
So yes it is possible. But id say its all about how tight or not tight the house is. A good indicator is how much oil or other fuel you went through in the past on very cold days. ANd what was the sizes of those heaters. I must have very good coal this year as the stoker is idling more than it usually does when its this cold. I also bump up the water temps above the usual 160 -180 to get more heat out of the finned baseboard on these extremely cold days.

Foxy24 · Post by **Foxy24** » Mon. Jan. 28, 2019 6:32 pm

Thanks for the replies everyone,sorry for not getting back right away, I've been busy tweaking with everything and trying to see what's working the best. In response to a few of your questions, actuall room temperatures range from 66-72 depending on outside temperature. We had a few warm days in a row and that seems to let the stove catch up a bit and get the rooms to 72 but as soon as it's in the teens or single digits I can't keep above 66 ish without my electric heat to help. I haven't been able to check temp on the side of the stove, and I don't think I'm losing to much heat out of my exhaust because I can easily touch the exhaust piping after the baro and it's probably not more than 120 degrees, I can hold my hand on it. I have my thermostat set way high at the moment so my auger is running 24-7 and my feed screw is turned all the way clockwise, yet I still don't have any hot coals dropping off the edge. I understand I don't actually want that but I thought I would be able to to run it fast enough that it would push hot coals off the edge and then back it down to get the desired 2 inches of Ash. I have a nice fire bed of maybe 5 inches and around 2.5 inches of Ash, so it's probably okay where it is set, I just don't feel like it is actually pushing coal as fast as it should? Also have you guys ever had issues of the coal not flowing well in the hopper? I will fill it totally full, and leave it for 24 hours and then check on it and it will "eat" a hole right above where my auger is and the rest stays sticking together until I give it a nice shake or rake it down. It doesn't ever starve the auger and might be something to just live with but I was wondering if it was normal or not? I would really like to continue heating with coal, and the way my house is set up the only efficient way for me to distribute heat is through my central ductwork. Maybe I need to look into a boiler with a heat exchanger? I know that these stoves are more meant to heat the area that it's in rather than push hot air around the house, but I just thought that even if I was only getting 120 degree air out of the front of the stove,the air would still be 80 degrees after a 200ft run in ductwork.

Thanks in advance for your help!

Foxy24 · Post by **Foxy24** » Mon. Jan. 28, 2019 6:42 pm

Sorry I missed your question k2. As far as how much "fuel" I've used in the past,it's hard to tell because my other heat source is electric. I'm not sure what btu unit my heat pump is, I'll have to check, but I do know that my electric bills in the 3 cold months of winter average $550. Hence why I'm trying so hard to go with coal with the hopes of heating for an entire season on 3-4 tons at $600-800. I maybe should have picked up a bigger unit but the price was too good to pass up on this 90k unit, and my coworker claims to heat his 3000sqft house using the exact same stove! Maybe it's just me haha. Also our house is not terribly old, it was built in 92 so I can't see that the insulation would be that terrible. Im slowly getting around to better insulating the place but it's definitely not as bad as an old farmhouse would be.

k-2 · Post by **k-2** » Mon. Jan. 28, 2019 7:04 pm

The stoker should be fine,as i said im heating 3000SF to 78 degrees in zero degree weather. Coal feed is important to get right. You may have to increase your coal feed a little at time to see what the max is. If you start pushing burning coals off the grate slowly back it off.

KLook · Post by **KLook** » Mon. Jan. 28, 2019 7:12 pm

It was said that it is maxed out and not pushing coal off the end......I think there is a problem with the stoker unit. Or the feed area with the coal eating a hole above the auger. When the temps get real low, that is when the small things make a difference. I had to learn on the fly as well with my small boiler. Judging from how much others are heating with older homes, you are leaving some heat on the table. I am not fluent in this unit, but I would look at the stoker to get it to push more coal.

Kevin

2001Sierra · Post by **2001Sierra** » Mon. Jan. 28, 2019 9:04 pm

What kind of controls are on your Kesytoker 90? I run a Coal-trol. If you have a thermostat and Keystoker controls, and as you say the unit is feeding 24/7 then if adjusted properly you should have 1.5 to 2 inches of ash at the end. Is the fire hitting the top of the stove when running flat out? The internal temp of my chimney vent runs about 260 on full feed, with stove side almost 500.

Foxy24 · Post by **Foxy24** » Mon. Jan. 28, 2019 9:29 pm

Thanks for the input everyone. Im running a digital Honeywell thermostat. Nothing fancy, more or less on/off and set the temp. The thermostat only controls stoker on/off time so I don't have blower controls integrated like the coal trol offers from what I read. The flame does seem to be reaching the top of the fire box and the coal is burning a bright almost white color. I'll bring a thermometer home from work tomorrow and check stove side temp and exhaust temp. I'll also try to take some pictures of the firebed at full burn to see if someone notices something I'm missing. As far as I know I have the stoker maxed out, but like I said I've never had hot coals closer than 2 inches from the end of the grate. I did do a quick inspection of the stoker system when I had the plates up to clean and re-cement. Looked to be in good condition but again, I'm a newbie with this stuff. Can anyone tell me what I'm actually adjusting when I'm turning the white nut? From what I can tell the nut is actually tight on a threaded rod, and when I'm turning the "nut" I'm turning the threaded rod either in or out of a piece of metal. I'm assuming it's just changing over stroke length of the stoker unit, resulting in either a short stroke=less coal, or long stroke= more coal. Anything else that's a high fail item on the stoker units? The surface is clean and smooth, no coal should be getting hung up. The piece of cloth that drapes over the pusher bar is a bit worn but I didn't suspect any performance issues due to it. I still have a nylon cam, I think I read some people have been updating to an aluminum one? Sorry for the abundance of information and questions, I'm excited and frustrated at the same time and I just want to enjoy a warm house when it's still 0 degrees outside!

2001Sierra · Post by **2001Sierra** » Mon. Jan. 28, 2019 9:45 pm

Boy you sure like typing! The rod adjustment nut is as you suspected, rotating it clockwise increses the stroke of the push block. The "cloth" as you put it is a pice of flat gasket material keeping coal from getting behind the push block. My nylon cam is 7 years old and still in fine shape.

Eab91276 · Post by **Eab91276** » Tue. Jan. 29, 2019 1:43 pm

Hello All,
I am new to this forum as well, but really appreciate all of the tips and tricks I've been reading over the last few months. It seems like I have a similar setup to Foxy24. I have a split level house built in 1979. We purchased it in 2017 and a Keystoker Koker furnace was installed by the previous owner in 2014. This unit is rated at 160k BTUs. They had the stoker connected to the first floor heat pump ductwork. This is my second heating season and it has been a trial and error experience. I replaced the original Honeywell thermostat with a simple Emerson digital one and moved it out of the family room that has a propane insert. I can keep my first floor within a 2 degree range no matter the temp. outside. When my stoker is running full on, my side thermometer reads 450-500 degrees. My air temp coming out of the vents is around 115 to 120 degrees. Even my farthest run to a back room (over 60 feet of duct with two 90 degree turns) has at least 110 degrees. One major thing I upgraded was the connection to my existing ductwork. The installer used two 8 inch diameter ducts from the unit to the ductwork. Way too small for the convection blower on the unit. I added two additional 10 inch ducts, so I could move more air. I also added a duct booster fan for that long run to the back rooms. Lastly, I cut a piece of sheet metal the same size as my air filter on the heat pump. When I switch to coal, I slide that metal in the heat pump to prevent heat loss through the returns. My stoker has returns right on the unit and I don't have them hooked to the existing ductwork. I would agree that your unit doesn't sound like it is burning correctly. Let us know if you have any updates.