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[AirForcePOL]

Ok folks, I need some help figuring out what is going on with my system.  Here recently I can't get a good burn time to save my life!  It was 15 deg last night and I only got about 7-8 hours on a entire load.  I've burnt all kinds of different wood from Locust and Walnut that was 15% moisture content to some chinese elm and oak that isn't exactly seasoned. It doesn't seem to make much of a difference.  So, here are the details of my setup.

HM 5000e, 85 ft of 1" Rehau running into my basement and then it transitions over to regular one inch pipe that is wrapped in bubble wrap insulation.  Once the pipe enters the basement wall it goes about 20 ft and then drops down 3 FT to my 20 plate HX.  Once it goes out of the plate exchanger it goes back up and through a hole in a wall and then back down about 8 ft to my furnace HX and then back up and over and back out to the boiler.  I drew up my setup and attached the picture if it worked.  In the picture I also drew up a close up of my plumbing at the water to air HX.  The round rings represent ball valves.  I'm using a badger GPD25-10SFC on medium (27 GPM and around 27 FT of head loss).  Temp on my stove is set at 184 with a 7 deg differential.  I've tried different settings and it doesn't seem to make much difference. 

Ok, now a little bit about my house.  It's right at about 2100 sq feet now with a new room addition that I'm working on. We keep it around 68-70 most of the time.  Some of the windows are really drafty and the house really doesn't heat well.  When the wind blows the right direction my furnace will kick on about every 5-10 min even when the outdoor temp is around 25 or so.  I had a Hardy H2 and could easily get 10-12 hours on a load with it. 

What I changed with the Heatmaster is replacing my junk lines, going from 3/4 pex to 1" Rehau and I added a plate exchanger for DHW.  I was hoping that I would be able to heat my 36x45 garage as well but how it's going now it won't be able to keep up.  I don't think it is the stove that's the problem, I think it's something in my setup.  Please feel free to give me your opinions! 

[AirForcePOL]

Try this link for the picture... 

[hondaracer2oo4]

So really the only things that you changed was replacing the crappy line set and replaced the boiler? Any idea what your temps leaving your boiler are and what the return temps back to the boiler are? If those look ok I would guess that you aren't exchanging the heat from the boiler to the water very well for some reason, boiler fan runs constantly trying to heat up the water but can't get the heat into the water for some reason. Something is a miss since you went from an H2 that holds not nearly the amount of wood that the 5000 holds and you cant get more then 8 hours.

[AirForcePOL]

yea replaced the boiler, added better lines and added a plate exchanger.  I don't know what my return temps are but I know I am only losing 1 degree tops from my boiler to the water to air HX.  When the stove calls for heat the recovery time really doesn't take long at all. Surely the DHW isn't taking that much heat, right?  I don't use a lot of water as there is only 3 of us in the house.  I just can't figure it out.  The quality of my wood is about the same if not better than what I have burned before.  I'm loading the stove plumb full every time and it's always empty when I go check it in the morning and when I get home.  Could it be that my water to air HX is clogged both internally and externally and that it isn't transferring heat properly and is running longer than it should be to satisfy my thermostat?  The air coming out of my vents is still very warm though.  I haven't checked the hx for cleanliness though....I do have it installed in my return but I have been pretty good about changing my filters. 

[dana k]

On the 5000 the draft on the back is adjustable.   If I run my draft at 100 percent open I burn substantially more wood.  Have been playing with it seems like 40 to 50 percent gives best burn times.  If your damper is wide open maybe tighten up a little.  Getting about 14 to 15 hour burn time.  Burning oak elm walnut.  Heating 1800sf poor insulated and basement and dhw.  This is first season with boiler so I'm still trying to figure it out.

[hondaracer2oo4]

No, the boiler fan is running to heat the water in the boiler, the btus that are then stored in the boiler have to go somewhere. Whether they are used in the house to heat the plate exchanger and the water to air hx or lost somewhere else is what you are going to have to figure out. How often is the boiler cycling to reheat the water? No way you are moving 27 gpm through your system either, I think max efficiency of 1 inch line is around 15 gpm, anything over that causes lots of friction loss. You should optimize your system so that your return temps back to your boiler while your furnace is running is around a 12-15 degree drop. I think we really need to know what the return temps are to the boiler and then we can move forward with figuring out where your btus are going. Also on a side note, you should only fill the boiler to there point that you have just enough coals to start the next load and your boiler is still at temp. If you fill the boiler full it will burn the same amount as if you had filled the amount it needed to just make it the 12 hours between loading. I know that you are having loading time issues and this may be why you filling it full. Sounds like you have a big heat loss though with your indoor furnace fan kicking on ever 5-10 mins at 25 degrees. I assume nothing has changed since last year in regards to that though, you had the same amount of time inbetween it kicking on at the same temps.

[AirForcePOL]

Right, I was referring to the recovery time of when my boiler temp drops and the blower kicks on to get the water back up to temp.  I will see if I can try and get a return temp tonight when I get home.  I only load the firebox full to ensure that I make it through the night.  The only thing that has changed is adding a new bedroom but it's unslated very well and shouldn't loose much heat at all.  It's still only about 430 sq ft bigger than it was last year but with a bigger stove. 

[hondaracer2oo4]

What is kicking on and off every 5-10 mins? Your furnaces blower in the house or the Heatmaster outside?

[AirForcePOL]

The furnace in the house kicks on every 10 min on average probably.   The boiler kicks in every hour or so

[hondaracer2oo4]

The indoor furnace kicks on every 10 mins and the boiler only kicks on once per hour? First off does the indoor furnace kick on any more often then it did last year at the same temperatures? I am very surprised that the owb only has to kick on once every hour with the indoor furnace kicking every 10. Also how long does the owb kick on for when it kicks on? Did you look at the rear damper door like dana asked about?

[AirForcePOL]

Furnace inside doesn't seem to run anymore than it normally does.  I'm going to try since plastic over the windows in my living room and see if that helps any.  I had some on there last year but I took it down this spring.  It cold be that the cold air from that room (north side of the house) might be making the thermostat kick on more than it needs to.  I have messed with the damper a little bit but it seems to burn better on 100% as there's a lot less smoke.  I just got home and the temp was 135 after 10 hours!

[hondaracer2oo4]

i think your damper on the mf is the issue, its is burning and pushing the heat right out of the boiler. You need to get yourself a nice hot coal bed established, once it is established you need to work on not losing it. You also have smoke because your wood isn't very seasoned. Probably 30% moisture content.

[Big Wood]

I would also check to see if you have any trapped air in your lines

[woodman]

Based on your description and the diagram I don't see anything that would indicate any problems. The up and downs in the basement may cause some air trapped in the line during initial full up, but you have been up and running long enough now it should all be purged. Clogged or dirty hx, air in the lines ect would equal less heat transfer and longer burn times. Without knowing anything else I would say either you have a LOT larger heat load than you previously had, or somehow your underground lines became compromised, or the wood you are burning has a higher mc than you think. Start with the most simple changes (plastic on windows, different spot from wood pile) and go from there. Good luck!

[AirForcePOL]

Thanks for all of your replies!  I changed my settings on the stove to 184 with a 10 degree differential and I put plastic on the widows on the North side of my house which is my coldest room.  I can already tell a difference in the room so hopefully I will also see a difference in my stove.  I just filled the stove like I have been and I'll see where I'm at in the morning.  It's 15 deg right now and going to get down to 11 tonight.  As far as the air in the lines goes I feel like I got it all out within the first few days of running the stove.