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[tweeker21]

I've been burning wood for around 3 years and haven't been overly impressed with the heat loss issue.  It's been difficult to keep the house warm.  I have my aquastat set to 180 with 10 degree difference and I've checked it with a heat gun and it's spot on. But after it goes through my water to water heat exchanger it only is 140 at my indoor boiler temp.  (I have baseboard heat)  I can never get it above 140.  Which it does heat my hot water as well but we run out of hot water often as well.  I'm only 50ft from house but I do have the OWB a 50/50 ratio of anti-freeze.  So I'm not sure it something is plumbed up wrong or what, guess i'm just curious if that's a normal heat loss.  Also all the plumbing from wood burner is insulated.  Any advice would be great thanks!

[ralphxj]

What is the water temp as it enters the house? The 140 you mentioned was after the heat exchanger? What is the water temp going out to the baseboard heaters?

[Bondo]

I'm only 50ft from house but

Ayuh,....   'n what sorta plumbin' did ya use for that 50 feet,..??

That's where all my heat loss is, due to me thinkin' I could build my own,....

[GCTerpfan]

You said the water temp at your indoor boiler is only 140 deg., correct? Do you know what the temp is on the outdoor boiler line at the supply and return of the heat exchanger?  How many plates is your heat  exchanger, maybe it is too small?

[braveblaster]

50/50 anti-freeze, as of coolant?

Pardon my ignorance for the question, this is my first year with an OWB.

[tweeker21]

Time to answer the easiest question first yes 50/50 anti-freeze incase I leave can shut it down and not worry about it freezing it's not easy to find people who want to feed the beast when it's cold out.  If I'm gone.  I will load pictures of my set-up when I get home from work and that will answer most the other questions thanks for the responses!

[kommandokenny]

50/50 anti-freeze, as of coolant?

Pardon my ignorance for the question, this is my first year with an OWB.

Some guys use antifreeze in their boiler water. 50/50
Case of pump failure, etc ....no frozen equipment.
If you go south for a while or away from home etc.
Draining causes rust,, so this is what to do.
Hope this helps?
kk

[braveblaster]

50/50 anti-freeze, as of coolant?

Pardon my ignorance for the question, this is my first year with an OWB.

Some guys use antifreeze in their boiler water. 50/50
Case of pump failure, etc ....no frozen equipment.
If you go south for a while or away from home etc.
Draining causes rust,, so this is what to do.
Hope this helps?
kk

Thanks. I was always told to use the nitrate mixture to take oxygen away from water thus preventing corrosion at the firebox. Didn't know antifreeze was also a solution.

Don't mean to take away from the main subject and in fact I just measured the temperature at the pex bringing hot water from the OWB to my heat/water exchanger and the temperature is around 140 degrees going in.

[BIG AL]

I can say that even with my homemade ins pipe and a 100' run I have about a 1 degree heat diff between the owb temp and my incoming water temp to my heat exchanger. I have temp gauges on both sides of my HX on supply and returns ,not much temp diff when nothing is calling for heat. I am also running a big pump (taco 2400-20-wb) and with a fairly flat run from my owb i figure flow at around 30 gpm.

[tweeker21]

My insulated pipe name is Insul-Seal 4 inch pipe with R-value 15 they advertise that loose 3 degree on a run between 80-100ft.  The pex tubing inside my insulated pipe is 1inch   My heat exchanger is a 80 Plate Water to Water Brazed Plate Heat Exchanger.  I do have a side arm on my water heater that the return water goes through.  Pump is a Grundfos UPS26-99FC which is a 1/6HP and 0-33GPM of flow.  I'd add pictures of my set-up but they must be to large haven't figured out how to do it yet.   And now I took my heat gun out to recheck all my readings and that doesn't work either!  So I will have to wait to give you all accurate readings.  But this will give you start on what i'm running.

[BoilerHouse]

My insulated pipe name is Insul-Seal 4 inch pipe with R-value 15 they advertise that loose 3 degree on a run between 80-100ft.  The pex tubing inside my insulated pipe is 1inch   My heat exchanger is a 80 Plate Water to Water Brazed Plate Heat Exchanger.  I do have a side arm on my water heater that the return water goes through.  Pump is a Grundfos UPS26-99FC which is a 1/6HP and 0-33GPM of flow.  I'd add pictures of my set-up but they must be to large haven't figured out how to do it yet.   And now I took my heat gun out to recheck all my readings and that doesn't work either!  So I will have to wait to give you all accurate readings.  But this will give you start on what i'm running.

The 3 degree temperature loss is about average... but lets put this in perspective.  If your pump is actually flowing 20 gpm (after accounting for friction losses) then you are losing 60 BTU per minute to the ground.  This works out to 16 million BTU for a 6 month heating season.  A cord of maple has 20 million BTU's in it.  Your stove is perhaps 50% efficient -although maybe it is more.  So each year you lose the equivalent of 1 to 1 1/2 cords of wood - just to the ground.  It sounds like a lot - but this is probably average for all of us who have an OWB.

[right2bear]

Tweeker21...

I have a couple of questions for you.

Do your baseboards have adequate space below and above them for proper convection? I only ask, because I also run a boiler to boiler system and had a lot of trouble getting set up the first year of service. I found after cutting back the carpet that was directly touching the bottom of our baseboards that it now works 3 times better.

Why do you only run your stove up to 180°? Most baseboards need at least 180° water to perform at their spec. btu's. By the time you lose btu's getting to your plate x'er, and then the loss through your x'er, I doubt your hardly getting hot enough water to your basboards for them to perform like they should.

I had to install a larger pump on my system, and bump up my stove to 200° and only allow a 5° difference. Mine recovers in about 10minutes now and keeps pretty consistent temps.

I would also question how big your plate x'er is? Is it sufficient for the sq. ft your heating? Also is it plumbed in properly?

[right2bear]

BTW... I installed a in line temp gauge before my side arm, and after my HX'er, and from the boiler, through 75' of underground, and 20' of pex in my basement to the gauge shown zero loss. From there to after the HX'er (my return temp) is around 175° (this is only when the pump is on from the thermostat demanding for heat though.)

I'm heating about 2500sqft this year, and have went through about 8 cords so far of primarily 2yr seasoned ash.

[hrc200x]

tweeker: You and I might have a very similar set up, I have a few year old heatmor 200 with insul-seal pipe and a 50 foot run, and maybe another 70 feet of pipe in the house. I don't have antifreeze though. The line from the boiler goes to a copper side arm first, then to a 80 plate heat exchanger. The indoor side of things are a fuel oil boiler with baseboard. I have gauges on the supply and return at the outdoor boiler and when nothing is calling for heat and I'm assuming the water heater is up to temp the gauges show very little, or no heat loss. When a zone calls for heat is when the heat exchange happens in the 80 plate (I don't have a wraparound pump that keeps the indoor boiler up to temp) and the supply/return will show a 6-10 degree difference. The temp gauge on the indoor boiler never gets above 160. The gauge on the front of the heatmor never gets above 170 even though the aquastat is set at 180.

Sometimes when you use a  laser heat gun on different metals the reading can be way off. shining mine on a aluminum chimney from a propane water heater, it showed 80 degrees, but there was no way you could hold your hand on it. I've heard of people putting masking tape over their copper pipe to get a more accurate reading.

The insulseal pipe can be a little cumbersome to fit together, did you get all the seams tight, glued, the foam caulked, and the plastic pulled over eachother?

Do you have a thermostatic mixing valve that is taking the hot water from the OWB and sending it right back out the return line before it even gets to the water to water, or the side arm?

Just tried shining the laser temp gun at a copper pipe and it showed 110 F. That was on a supply line out to the baseboard, the temp gauge on the front of the boiler is 155. Put a piece of blue masking tape on the line and the temp bounces around, but the hottest was 168, can't be possible as the water in the boiler is only 155.

[BoilerHouse]

My insulated pipe name is Insul-Seal 4 inch pipe with R-value 15 they advertise that loose 3 degree on a run between 80-100ft.  The pex tubing inside my insulated pipe is 1inch   My heat exchanger is a 80 Plate Water to Water Brazed Plate Heat Exchanger.  I do have a side arm on my water heater that the return water goes through.  Pump is a Grundfos UPS26-99FC which is a 1/6HP and 0-33GPM of flow.  I'd add pictures of my set-up but they must be to large haven't figured out how to do it yet.   And now I took my heat gun out to recheck all my readings and that doesn't work either!  So I will have to wait to give you all accurate readings.  But this will give you start on what i'm running.

The 3 degree temperature loss is about average... but lets put this in perspective.  If your pump is actually flowing 20 gpm (after accounting for friction losses) then you are losing 60 BTU per minute to the ground.  This works out to 16 million BTU for a 6 month heating season.  A cord of maple has 20 million BTU's in it.  Your stove is perhaps 50% efficient -although maybe it is more.  So each year you lose the equivalent of 1 to 1 1/2 cords of wood - just to the ground.  It sounds like a lot - but this is probably average for all of us who have an OWB.

Willie PM'd me and helped me sort through some of my calculations.  Seemed I had a brain cramp.  Heat loss in BTU's is based on temperature loss x flow in pounds.  So looking at the original post again, the heat loss in BTU per minute would be 3 x 20 x 8.3 (pounds in  a gallon).  Rounding off a bit, this would equal 500 BTU/minute or 700,000 BTU/day. At 50% stove efficiency, this could equal two cords of wood per month.   It is possible the flow is less than 20 gpm, this could be easily calculated with a pail and watch at the boiler return.
All systems will loose some heat to the ground -just the way it is.  My temp gauges, which are Ashcroft industrial, show no temp diff, but the stated accuracy on them is plus/minus 3%.  My pump spec's at over 20 gpm, but actual flow is 7 gpm.  Regardless, from my 7 cord annual consumption, I am sure I loose between one and two cords to the ground.