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Boot

New Member
Oct 21, 2022
3
Northern Maine
Hey folks. First time Posting here! This site has been extremely helpful.
I looked through the stickies first, and didn’t really see anything.
Quick overview of my setup: northern Maine, OWB, Central Boiler 560HDX. Installed last January. (Boy that was fun!) pumped in series to two 30 plate heat exchangers transferring heat to domestic water and to my primary loop of my baseboard heat. My indoor boiler is still included in my primary loop and has its aqua stat set to kick in if OWB looses heat for some reason.

My question: long story short, should I have my indoor primary loop circulating all the time through the plate heat exchanger? As it sits right now, the primary loop only circulates and pulls heat out of the exchanger when there is a zone calling for heat. Would it be more efficient to run the primary circuit all the time to keep it warmer and reduce larger temperature fluctuations when there are less calls for heat? I would be turning it with a Taco ECM pump.
Also another thought to increase efficiency- my boiler water temp differential is ten degrees, desired temp 185. Boiler begins to burn at 174.9- would it be better to increase the differential? My reasoning behind this- of course, I’m running a gasser that takes time to reach 100% full burn. Once it gets there, even on the coldest day it’ll only burn at 100% reaction chamber efficiency for 5-8 minutes. If I increase the differential, it’ll burn at 100% for more time. I know this may be a dumb question. It’s all good, if I deserve a roast, I’ll take it! 😅
 
My setup goes, 80k 20 plate ( 40k roughly if you do the math ) and then water-air HX and my circulator runs 24x7.

I run mine with 10° degree spread with a desired temp of 180°F. I believe standard pex is good for 200°F so that's why I keep mine a little lower.

How do you like that boiler so far ?
 
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My setup goes, 80k 20 plate ( 40k roughly if you do the math ) and then water-air HX and my circulator runs 24x7.

I run mine with 10° degree spread with a desired temp of 180°F. I believe standard pex is good for 200°F so that's why I keep mine a little lower.

How do you like that boiler so far ?
Gotcha. I’m not sure how water to water vs water to air works, and if it’s the nature of that system to need constant circulation.
I like the boiler, i grew up with an old Amish cook stove for heat and this is a welcome change… having to load it every 24-36 hours sure is nice. That’s the only comparison I have, operation wise.
The initial investment sure was a big chunk, but it sure makes it worth it when I hear co-workers moan about oil prices.
 
Not sure I have a handle on your system. The OWB supply circuit runs 24/7? Correct? If so I think I would want the indoor primary loop that includes your IWB to also run to keep the IWB hot. Otherwise the oil would be cutting occasionally with no real need? If no call for heat? I.e., the primary indoor loop just keeps your IWB hot. Then the IWB supplies the calls for heat and lights the oil if its temp drops too much. Did I get that right?
 
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Not sure I have a handle on your system. The OWB supply circuit runs 24/7? Correct? If so I think I would want the indoor primary loop that includes your IWB to also run to keep the IWB hot. Otherwise the oil would be cutting occasionally with no real need? If no call for heat? I.e., the primary indoor loop just keeps your IWB hot. Then the IWB supplies the calls for heat and lights the oil if its temp drops too much. Did I get that right?
Correct, outside runs constantly. Inside runs only on demand, usually doesn’t cool enough to kick indoor boiler on, unless there’s a stretch of warm weather. (In that case, I’ll turn the indoor aqua stat way down. I’m teaching myself all of this, and am working on an idea for a better controller) or instead of all that, I could run the circulator indoors all the time. Efficiency is the name of the game, no?
In this case, I’ll probably just run my primary indoor loop circ on constant power.