Print

[woodburner85]

This fall I installed a Heatmaster SS 10000 to existing underground lines from previous stove.  The previous stove corroded through 3 years ago.  I am heating a old farmhouse 2000 square feet with very little insulation. Baseboard radiator heat. Around one hundred and twenty feet of underground between house and boiler. 40 plate water to water plate exchanger and 20 plate for hot water on return side. taco 009 f5 pump . I have the stove set at 180 degrees and I am showing 15 to 20 degrees cooler in the house on the back up furnace thermostat.  With the below zero weather recently I can not keep the house above sixty four degrees without setting stove over 190 but that seems pretty risky.    Could I have an undersized pump or plate exchanger or do you think that my underground could be that horrible.  If it is underground would it pay to temporarily install thermopex above ground for the winter and how much heat loss could I expect having it above ground?  How much wood am I wasting if I am losing that much heat underground?   How much and where would be a good place to buy a laser thermometer to do some checking and how accurate are they?  Thank you   

[DaveWertz]

Im having similar issues. On single digit nights and low to mid teens my house stays 4 degrees colder than the thermostat. I have baseboard and upgraded to taco 0011 and only have a 50ft run of 3 wrap insulated pex amd still get chilly. Im calling in a pro tomorrow. Its sucks trying to figure it out lol. But id say it be worth the money to get insulated lines and lay them above ground. Depends on what wrap you get. Good luck.

[RSI]

Bad underground lines will show up as excessive wood usage, not trouble heating the house.

How cold is the return water going back to the boiler? Are the plates around 5x12" or are they smaller?

Normally there is about a 20 degree difference between the primary side and the secondary side of the heat exchanger on a system like that. Baseboard heater output drops off fast with lower temperature. You will probably need to add more baseboard heaters or some other type of heat exchanger to get the output you need.

If you way oversize the plate it may gain you a little but probably not enough. I would go with at least an 80 plate if you try that.

[DaveWertz]

Sorry to steal this thread. RSI. How exactly does a heat exchanger work for baseboard heat? I dont quite follow how heat exchangers work for something like this. I always thought a heat exchanger was for something like forced air units?

[hondaracer2oo4]

Dave, heat exchangers are any device that converts the incoming heated medium to some type of other heated medium. So for Water to Air heat exchangers you convert the hot water medium to hot air medium. With a Forced hot water baseboard set up you are converting the non pressurized hot water medium from the outdoor boiler to the pressurized hot water medium of the indoor hydronic heating system. Wood burner, please let us know what the temp is before it enters the plate exchanger on both the outdoor boiler and the indoor boiler systems and well as what temperature is after it leaves the exchanger on both the outdoor boiler side and the indoor boiler side when you have the house zones calling for heat. I would assume that the backup system (oil or gas) in the house is able to keep up with the demand and keep the house at the correct temperature? If that is the case then you are not converting that water from the outdoor boiler to the indoor boiler effectively. The temp readings will tell us the whole story.

[yoderheating]

 RSI is correct, its hard to heat an uninsulated space with baseboard unless you have a lot of it. 

[idahohay]

Woodburner, your Taco 009 with no head loss will circulate maybe 8 gpm. When considering the 120' run(x2), the 40 plate exchanger, any other fittings (possibly your 20 plate as well- you didn't say how it was hooked up)you would be working with 20 feet of head or more.   Now your 009 is moving maybe 5 gpm.  Your 40 plate might have a rating of 400,000 btu/hr. but that is with 180 deg. water at over 40 gpm! 

A fphe is your friend if you want reduced temps as in reducing boiler temps to infloor  temps but not so much for radiators.  So in my non-professional opinion, a larger pump will help, at least on the boiler side. 5gpm(if I am close in my guess) seems way too little for a unit capable of 500,000 btu/hr.

[victor6deep]

I would've spent the money on insulation and new windows before dumping money into wood and a OWB. After that then buy the OWB. Guy down the road from me has the similar setup and is ALWAYS cutting wood. My house stays 70 constant running 18hr plus burn times set at 150-160. Make the home efficient and then add the stove etc. My stove sets maybe 60ft from my house and I run triple wrap double tiled pipe made in grand rapids michigan eze flex or something like that, pretty efficient and strong stuff.

[yoderheating]

The best way to see where the problem actually is would be to check the temperature of the water as it comes out of the 40 plate and heads toward the first baseboard. If its 160 or above adding pumps or a larger plate heat exchange isn't going to do much and the problem is in the amount of baseboard you have. If its below 160 then adding a larger pump may have some benefit.

[willieG]

average numbers for a typical 3/4 one pipe slant fin baseboard is (rated btu per foot of basebaord)
140 degrees delivery ----300 btu
150---350
160---400
170---500
180---550
190---650
200---700

[yoderheating]

Yes it is very important to get that number up as high as possible.  But when using a heat exchanger you will never get the temp up as high as the outdoor furnace.

[willieG]

taht is why if your original boiler was sized close you may need more baseboard when you go to the OWB...your deliveryy temps will not likley be as hot as the indoor boiler?

[yoderheating]

 Very true! I always tell customers if they have an indoor boiler that must be run over 160 to heat the home they may be in trouble if they hook a furnace to it. If they can test the existing boiler and it will heat the home at 160 or below we are good to go.

[CountryBoyJohn]

Gotta disagree with you Mr. Victor.  My house has terrible insulation and windows.  Installing new windows and insulation might have reduced my heating bill by 25%, and I think that's being generous.  My stove cut my first bill by 50%.  I imagine my November bill will be even greater savings.  Upwards of 75%.  I will be saving WAY more using the stove rather than sinking money into windows and insulation.  I will likely start installing new windows in the next year or two.  Although it will still be hard to justify, because I will just be saving wood now, and not necessarily money. 

[victor6deep]

Gotta disagree with you Mr. Victor.  My house has terrible insulation and windows.  Installing new windows and insulation might have reduced my heating bill by 25%, and I think that's being generous.  My stove cut my first bill by 50%.  I imagine my November bill will be even greater savings.  Upwards of 75%.  I will be saving WAY more using the stove rather than sinking money into windows and insulation.  I will likely start installing new windows in the next year or two.  Although it will still be hard to justify, because I will just be saving wood now, and not necessarily money.

Must be you work for free? Just wait til you insulate better and add better windows then you will be on the sofa drinking beer and eating popcorn like me.