circulator help needed

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J&J Farm

Member
Oct 24, 2021
16
Central Pa
Hello to everyone... Could use some help with my system. Just got my outdoor boiler going (all is well) and noticed i have no circulation to my indoor system. Let me explain my system. I have a oil fired furnace with radiators in the house. I installed a outdoor wood boiler with 2 zones. 1 goes to garage with a 24-7 circulator. It is doing fine. 2nd goes to house. Doing fine. The zone to the house has a hot plate exchanger in the house. Out of the hot plate to the house furnace is a circulator. Doing as it should. The problem is the house circulator which is the preexisting system does not circulate because the house thermostat is not calling for heat. I don't want to rewire it to run 24-7 like the other 3. It will cook us out. How do i get the house circulator to turn on and off with the heat in the house??? Thank you for all who look and help us.
 
I’m not sure I understand, either. Is it a forced air furnace? If so, what would be wrong with the circulator to the furnace running 24/7? The only problem is if you have your furnace fan running all the time, then you would get cooked out. Otherwise, if their isn’t air flowing through the furnace, you wouldn’t be getting much heat into your house. I have a coil in my LP furnace. The circulator for it is setup on a controller that I can set the temp on. As long as the water is above the temp I set, the circulator runs 24/7 and the LP doesn’t get used. If the water temp falls below the set temp, the water circulator shuts off and the LP burner kicks on. That only happens when we aren’t home for an extended period of time, or once or twice in the fall or spring before I start or quit using my boiler.
 
I’m not sure I understand, either. Is it a forced air furnace? If so, what would be wrong with the circulator to the furnace running 24/7? The only problem is if you have your furnace fan running all the time, then you would get cooked out. Otherwise, if their isn’t air flowing through the furnace, you wouldn’t be getting much heat into your house. I have a coil in my LP furnace. The circulator for it is setup on a controller that I can set the temp on. As long as the water is above the temp I set, the circulator runs 24/7 and the LP doesn’t get used. If the water temp falls below the set temp, the water circulator shuts off and the LP burner kicks on. That only happens when we aren’t home for an extended period of time, or once or twice in the fall or spring before I start or quit using my boiler.
Thank you for your response... That is incorrect.... It is a OIL FIRED furnace. Water Boiler with radiators in the house. The system is set to heat up the outdoor boiler if it goes out. For instance,, the wood boiler goes out or drops temp,,, the water that circulates from the OIL boiler heats up the hot plate, that returns to the wood boiler to keep from freezing.... AS stated in MAPLE 1 response, if I turn up the thermostat in the house then the oil furnace will come on and that's when the circulator will circulate thru my radiators.... Hoping you now understand the system I'm using.....
 
Sounds like you need a relay which would be controlled by the thermostat to turn on the house circulator. I have one for my setup that turns on the blower fan in my forced air furnace.

You would need a second thermostat dedicated to that relay. There may be a way to do it all from one, but it is beyond my knowledge.
 
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We dont have a lot to go by here as far as your system goes, and controls etc.. Or all the piping.

Out of the hot plate to the house furnace is a circulator. Doing as it should.

Does that mean the OWB is keeping the oil boiler hot all the time no matter what the thermostat is doing? What are temps of the oil boiler? You might just need to adjust an aquastat. One that controls the oil burner. What is it set at?
 
I have an aquastat on mine which shuts off the wood boiler and turns on the oil boiler when my storage temps get below around 105F
 
Sounds like you need a relay which would be controlled by the thermostat to turn on the house circulator. I have one for my setup that turns on the blower fan in my forced air furnace.

You would need a second thermostat dedicated to that relay. There may be a way to do it all from one, but it is beyond my knowledge.
Thank you for your reply... Your response gives me a avenue to seek within.... What type of relay ( brand and specs ) are you using in your setup???
 
We dont have a lot to go by here as far as your system goes, and controls etc.. Or all the piping.

Out of the hot plate to the house furnace is a circulator. Doing as it should.

Does that mean the OWB is keeping the oil boiler hot all the time no matter what the thermostat is doing? What are temps of the oil boiler? You might just need to adjust an aquastat. One that controls the oil burner. What is it set at?
Thank you for your time and efforts!!!! Here is my system... PICS 1-3 are the outdoor wood boiler. The left circulator is the zone to the house. The right circulator is the zone to the garage.... PIC 4 is the outdoor boiler with thermometer and aquastat which is controlling the blower motor in PIC 5..... PIC 6 is the exchanger in the garage which is a constate circulator... PIC 7 is where it enters the house.... PIC 8 is the indoor hot plate with the circulator between the exchanger and OIL FURNACE.... PIC 9 is the overall... PIC 10 is the front of the OIL FURNACE...... The objective is the outdoor wood boiler heats the garage 24-7 and the house with supplying domestic hot water. Hence the indoor exchanger or hot plate. If the outdoor wood boiler goes out, the furnace will take over and supply hot water to the outdoor boiler... MY PROBLEM is the oil furnace fires off to supply domestic hot water and heat to the house which has several radiators.... The aquastat on the house boiler is set below the temp of the outdoor boiler, and I'm burning oil for hot water and heat for the house, while the outdoor boiler is burning wood.... I hope you can understand the system.... I cant get the outdoor boiler to control the house heat and domestic.... I'm missing something.... Thank you again for your efforts.....

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You talk of an oil fired furnace, and an oil fired boiler. Are they the same thing, or do you have both? From your first post, I thought it was an oil fired, forced air furnace. Is it an oil fired boiler that feeds a coil in a forced air blower? Or perhaps just an oil fired boiler that doesn’t feed a blower fan at all, just radiators with hot water. I don’t see any forced air unit in your pictures.
I think I was taking the word “furnace” in the wrong way.
 
I think the OP was interchanging the use of furnace and boiler. It looks like just a boiler with feed to radiators. No furnace.

To the OP, in your last picture, is the circulating pump on the right side of your oil boiler is the one that you need to control to heat your house? What do you have your water temp set to on your oil boiler? Low temp & hi temp. What water temperature are you seeing from the plate exchanger to the oil boiler?

What happens if you set your hi temp on the boiler lower than the water temps coming from your OWB and have a call for heat? Would your circulator start and the boiler not fire?
 
The OWB should not be controlling house heat. All it should be doing is keeping your oil boiler hot. Is it doing that? How hot?

And can you post a pic of your oil burner aquastat settings.
 
You talk of an oil fired furnace, and an oil fired boiler. Are they the same thing, or do you have both? From your first post, I thought it was an oil fired, forced air furnace. Is it an oil fired boiler that feeds a coil in a forced air blower? Or perhaps just an oil fired boiler that doesn’t feed a blower fan at all, just radiators with hot water. I don’t see any forced air unit in your pictures.
I think I was taking the word “furnace” in the wrong way.
Sorry for not understanding the correct wording for the the post I was writing... I am new to understanding these terms. Raised in the city with oil fired boiler, we called it a furnace. Living in mobile homes with LP, we called it a furnace. Thank you for bringing this to my attention.....
 
Sounds like you need a relay which would be controlled by the thermostat to turn on the house circulator. I have one for my setup that turns on the blower fan in my forced air furnace.

You would need a second thermostat dedicated to that relay. There may be a way to do it all from one, but it is beyond my knowledge.
Thank you for you reply. I was told the same by a friend and I am stopping by today to see their setup....
 
We dont have a lot to go by here as far as your system goes, and controls etc.. Or all the piping.

Out of the hot plate to the house furnace is a circulator. Doing as it should.

Does that mean the OWB is keeping the oil boiler hot all the time no matter what the thermostat is doing? What are temps of the oil boiler? You might just need to adjust an aquastat. One that controls the oil burner. What is it set at?
Thank you for your reply. YES, OWB is doing as you say. The aquastat on the OWB is set to 180 and the oil fired boiler is set to the lowest settings of 140 cutout and 130 come on.
 
I think the OP was interchanging the use of furnace and boiler. It looks like just a boiler with feed to radiators. No furnace.

To the OP, in your last picture, is the circulating pump on the right side of your oil boiler is the one that you need to control to heat your house? What do you have your water temp set to on your oil boiler? Low temp & hi temp. What water temperature are you seeing from the plate exchanger to the oil boiler?

What happens if you set your hi temp on the boiler lower than the water temps coming from your OWB and have a call for heat? Would your circulator start and the boiler not fire?
thank you for your reply. Yes, it is a boiler with feed radiators... Yes, the circulator on the oil boiler is what feed the radiators in the house for heat. The settings on the oil boiler aquastat are the lowest I can set them, 140 cutout and 130 cut in. The PLATE EXCHANGER temps are being checked with a laser heat gun which is going thru 1" pex. When checking the OWB water temp at 165 the heat exchanger tepms are 87 coming in and 77 going back to the OWB. The other side is 82 out of oil fired boiler and 109 going back in. I know the numbers are low, but the only TEMP GUAGE in the system is on the OWB, which is new. Hope this helps, and thank you
 
The OWB should not be controlling house heat. All it should be doing is keeping your oil boiler hot. Is it doing that? How hot?

And can you post a pic of your oil burner aquastat settings.
Correct and that is what the OWB is doing... lf you look at a earlier post to FORMER FARMER I posted them.
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THANK YOU
 
Correct and that is what the OWB is doing... lf you look at a earlier post to FORMER FARMER I posted them. View attachment 289683THANK YOU
That is the same boiler as i have for back up.
My wood fired boiler is plumbed to charge storage,that is it's only job.
I run a plate HX just water on the wood boiler side.I have a circ that draws from the wood boiler side and runs through the HX with an aquastat on the feed line,when that temp drops below 105 it shuts off the circ and fires up the oil boiler.
The oil boiler is tied into the hot line coming from the HX with close tee's.This side of the HX has antifreeze for the underground lines and my house.
If i know i am going to run the oil for an extended time i will turn off one valve from the HX to storage,that stops heating the storage by the laws of thermodynamics.
Other than the valve i like to turn off it's all automatic.
The oil fires up if i have a town trip and don't get back till late,then all i have to do is fire the wood boiler and once temps are over 105 on that side the oil shuts down and the circ for the plate HX starts suppying heat from storage or the boiler whichever has the hottest supply.
 
thank you for your reply. Yes, it is a boiler with feed radiators... Yes, the circulator on the oil boiler is what feed the radiators in the house for heat. The settings on the oil boiler aquastat are the lowest I can set them, 140 cutout and 130 cut in. The PLATE EXCHANGER temps are being checked with a laser heat gun which is going thru 1" pex. When checking the OWB water temp at 165 the heat exchanger tepms are 87 coming in and 77 going back to the OWB. The other side is 82 out of oil fired boiler and 109 going back in. I know the numbers are low, but the only TEMP GUAGE in the system is on the OWB, which is new. Hope this helps, and thank you

I think I’d put a heat gauge at least in my supply at the house, just to make sure I’m wasn’t loosing a lot of heat in my outside line. I know it’s a bit difficult to check the pipe temp with an infrared thermometer.
 
I’ve been thinking more on your exchanger temps. They don’t make sense to me, but that is possibly because I don’t understand exactly how it is there. So take the following for what it’s worth….
I would understand from your numbers to say that the heat coming into your exchanger from the OWB is under 130. You say, I think, that it shows 87 supply from OWB, 77 return to OWB. On the other side, I would understand 82 into oil boiler, 109 out of oil boiler. So, if we take the cut in temp on your oil boiler of 130, and say the temp from the oil boiler going into the HX is 130, which shows on your pipe as 109. That is HIGHER than the supply (87) from the OWB into the HX, hence the reason the oil boiler still kicks on.
But like I said, it’s a bit foggy trying to understand while not being able to see from over 1,000 miles away.
 
Your mentions above of things doing fine - they seem to not be doing fine. Almost impossible to know what is going on here from what is posted. Accurate temperatures are needed. Clearly seems that the oil is cutting in because heat isn't getting from the OWB to the oil boiler. Somehow.