Outdoor Wood Furnace Info

Outdoor Furnaces - Manufacturers WITH EPA-Certified Models => Central Boiler => Topic started by: Jack72 on March 12, 2012, 07:23:47 PM

Title: Lower water temp
Post by: Jack72 on March 12, 2012, 07:23:47 PM
Hello

I see most are lowering their water set points.   I heat my water so I can't go below 170 with the thermostatic valve right otherwise I won't get flow.???   Also I thought it was bad below 170 range because it introduced more moisture and creosote in the firebox??   I don't know if the other brands (besides CB )   don't  have the thermo valve or not
that's why they can go so low???             thanks for everyone's input.

 Jack
Title: Re: Lower water temp
Post by: RSI on March 12, 2012, 07:30:49 PM
On a gasser you need to keep it hotter or it takes to long to start gasifying.
Title: Re: Lower water temp
Post by: johnybcold on March 12, 2012, 09:38:20 PM
I don't have the thermostatic valve it seemed like another restriction my unit is set at a low of 177 and a high of 187
Title: Re: Lower water temp
Post by: muffin on March 13, 2012, 06:01:01 AM
Hello

I see most are lowering their water set points.   I heat my water so I can't go below 170 with the thermostatic valve right otherwise I won't get flow.???   Also I thought it was bad below 170 range because it introduced more moisture and creosote in the firebox??   I don't know if the other brands (besides CB )   don't  have the thermo valve or not
that's why they can go so low???             thanks for everyone's input.

 Jack

Is your thermostatic valve really set to 170?  Mine is 150.  170 seems really high.
Title: Re: Lower water temp
Post by: Jack72 on March 13, 2012, 06:50:54 PM
Muffin

I don't want to sound dumb but I didn't know it was adjustable   I thought it was factory set internally no.?.


Thanks Jack
Title: Re: Lower water temp
Post by: johnybcold on March 14, 2012, 04:50:12 PM
The valve or the one my dealer sells have a thermostat like a car you can change it to change the temp
Title: Re: Lower water temp
Post by: boilerman on March 14, 2012, 08:52:38 PM
I think there may be some confusion here. The thermostatic valve Central Boiler is sending with all their wood furnaces allows for full flow through it as long as the incoming water temp is 170 degrees or warmer. If water drops below 170 and continue to drop because you have run out of wood or your heatload is too heavy, the valve will gradually send more & more water back to the owf and less to your homes exchanger. If the temp drops down to 150 degrees, about 95% of the water will be returned to the owf while 5% will continue to flow through the home exchanger and would allow your existing heating system to feed some heat back to your owf, keeping lines etc from freezing. My dealer says they are not adjustable and there are no lower rated thermostats available in their parts book. Their goal is to give the owf an opportunity to recover and not allow return water below 150 degrees to cause condensation in the firebox.
Title: Re: Lower water temp
Post by: muffin on March 15, 2012, 09:30:30 AM
Muffin

I don't want to sound dumb but I didn't know it was adjustable   I thought it was factory set internally no.?.


Thanks Jack

It is not adjustable, hard set to 150.  I assume your would be 150 too.  Perhaps as stated above, 170 for full flow, 150 for 95% return is the confusion.
Title: Re: Lower water temp
Post by: morsejh on March 15, 2012, 07:26:21 PM
There is some nice info here on the set points for the thermo valve, and I wish I had seen it during our 'initiation' (first year with the boiler).  We were told we could get a longer warranty if we installed our thermo valve, so of course we did, and were told it was set at 150.  I've noticed we get very little flow until the outdoor reading is at least 161.  That became a concern for a while.  Makes sense it starts to scale back at 170, and is mostly closed at 150; that matches what I have witnessed.

To the topic at hand,  I've tried the lower water temp settings.  I'm a geek, if it's computerized, I'll get into settings.

I find lower temp helps on marginal heating days.  Less wood consumed, and a better match for the heat needed.  In other words, if it's 50 and sunny or 60 and cloudy, 170 is a good setting.  My heat is distributed old-school style in the house, using hot water (via heat exchanger), and there's a delay between the heat delivered to the radiators and when the indoor thermostat trips.  That's why adjusting the set point helps, less of a heat slam during low heat needs.  I doubt it helps if you use forced air, and may even create more trouble than it is worth.

Below 32 degrees outside, I run the factory default 185.
Title: Re: Lower water temp
Post by: Jack72 on March 15, 2012, 07:47:28 PM
I think there may be some confusion here. The thermostatic valve Central Boiler is sending with all their wood furnaces allows for full flow through it as long as the incoming water temp is 170 degrees or warmer. If water drops below 170 and continue to drop because you have run out of wood or your heatload is too heavy, the valve will gradually send more & more water back to the owf and less to your homes exchanger. If the temp drops down to 150 degrees, about 95% of the water will be returned to the owf while 5% will continue to flow through the home exchanger and would allow your existing heating system to feed some heat back to your owf, keeping lines etc from freezing. My dealer says they are not adjustable and there are no lower rated thermostats available in their parts book. Their goal is to give the owf an opportunity to recover and not allow return water below 150 degrees to cause condensation in the firebox.

Boilerman thats what I thought       

I know that their may be other types out their but thats the way ours (CB) works they way you described.             Thanks Jack