OWB not transfering heat into oil burner
- Thread starter Mahoney86
- Start date
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As am I. My water conditioner has a purple dye to it. If I open the OWB purge, I get a steady stream of purple. If I open the OWB supply I get purple. If I open the pressure relief valve on the backside of the boiler where my OWB return is, I get purple water.
I just think for some reason or some how I am not getting that water to push into my base boards. I can only think it is a pressure or air issue.
I just think for some reason or some how I am not getting that water to push into my base boards. I can only think it is a pressure or air issue.
maple1
Minister of Fire
Oil side works perfectly on its own.
It would appear it’s going through the boiler but it doesn’t make its way up into the baseboards and get circulated
maple1
Minister of Fire
1” lines from boiler all the way to house. I downsized to 3/4” lines in the house transitioning to the 3/4”’lines on the boiler. I could not find 1” lines locally
maple1
Minister of Fire
maple1
Minister of Fire
That's not a very high head circ. Could be the most of the problem. Just not moving very much water.
Possibly, shame I literally just bought it because I thought maybe the old one was bad.
Any thoughts on the connections to the Flat plate? I’ll try that tomorrow and if still nothing I’ll upgrade to a different circ pump
Any thoughts on the connections to the Flat plate? I’ll try that tomorrow and if still nothing I’ll upgrade to a different circ pump
maple1
Minister of Fire
I would get a bigger circ in place before I swapped the HX in. If you aren't moving enough wood water now, the HX won't improve things. It will actually add head. If you get a proper sized circ, it might do OK without the HX. Since you said the oil side seems to be working fine.
I’m no expert but I would be really surprised if I’m not moving enough water, I guess anything is possible.
When I open the valves the water comes out with some good force.
The heat exchanger was delivered this afternoon so i think I’m definitely going to use it regardless
When I open the valves the water comes out with some good force.
The heat exchanger was delivered this afternoon so i think I’m definitely going to use it regardless
maple1
Minister of Fire
I'm away from my computer so can't get everything in front of me at once. But - you have 75', one way, of 1 inch pex. Correct? And how much 3/4"?
I have to agree on the circ sizing. I got to thinking the same thing about all the components you were saying you had on the loop. Like maple said if you can't move the water you'll have problems.
@Mahoney86 I don't think your drawing on the HX plumbing was right. You need to make sure the hot side from OWB boiler and the hot side to oil boiler are on the same end. You want an opposing flow through the HX.
@Mahoney86 I don't think your drawing on the HX plumbing was right. You need to make sure the hot side from OWB boiler and the hot side to oil boiler are on the same end. You want an opposing flow through the HX.
maple1
Minister of Fire
One way? I did some quick looking and from what I saw the absolute most you'd flow is maybe 5gpm. That is not taking into account whatever fittings you also are going thru or whatever else might be adding head, just assuming straight pex. One elbow adds about 10' of pipe length. That's a killer on the 3/4.
Yup, one way. Each line has 4 elbows as well so eeek. My local hardware store has 1” pex in White but only 5’ sections. I guess i could tear all this stuff out and stick with 1” to the heat exchanger
maple1
Minister of Fire
You could use 1" copper too, right over to where the 1" pex comes thru the wall. A bit spendy but...
Also, not sure, but internal flow thru the inside boiler could have a short circuit between the bottom fitting and the relief tapping. Just a guess. Could be the shortest path so minimal chance for mixing. I would definitely first work on getting my wood boiler loop flow where it should be though.
Also, not sure, but internal flow thru the inside boiler could have a short circuit between the bottom fitting and the relief tapping. Just a guess. Could be the shortest path so minimal chance for mixing. I would definitely first work on getting my wood boiler loop flow where it should be though.
I don’t know if this helps anything but I just did some temperature readings with my cheapo infrared thermometer. My OWB has not ran in over 36 hours and it’s 60 degrees today so no boilers are running.
Bottom pipe on oil burner is 147.2
OWB supply pipe at oil burner is 140.5
Return line pex back to OWB is 139
Analog Temp gauge on oil burner says 140
The temperature on the wood boiler controller reads 148
The supply pex at OWB is 139.8
The return pex at OWB is 137
With the elevation difference of where my OWB sits compared to the basement location of my oil burner I am getting a psi reading of 5psi on my oil burner
Bottom pipe on oil burner is 147.2
OWB supply pipe at oil burner is 140.5
Return line pex back to OWB is 139
Analog Temp gauge on oil burner says 140
The temperature on the wood boiler controller reads 148
The supply pex at OWB is 139.8
The return pex at OWB is 137
With the elevation difference of where my OWB sits compared to the basement location of my oil burner I am getting a psi reading of 5psi on my oil burner
stee6043
Minister of Fire
Silly question - when you're trying to run the OWB without the boil boiler does the return piping on the oil boiler get warm at all? Have you tried running the oil boiler circ at the same time you're running the OWB? Is it possible you've got a check valve at the oil boiler messing with your flow?
The return piping to the OWB does get warm but the return piping on the oil burner does not. I make sure the oil burner circulator is running when the OWB is circulating as well.
Anything at this point could be possible but I do not see a check valve anywhere.
stee6043
Minister of Fire
A question about your piping - you tied your return (blue) into what appears to be your pressure relief plumbing on the oil boiler. Is there a connection coming from the house return that isn't shown on that same pipe? I assume there is but it's not pictured. Also - is that a bypass of some sort coming off the supply side of the oil boiler? This is the smaller diameter copper not far from your OWB additions. Does that line have a shutoff?
Assuming your return is pulling from a house return line is there something in your plumbing that prevents the OWB circ from sending supply straight through the oil boiler, straight to the blue return line without going through the house?
You're correct the OWB return piping is plumbed into the oil boilers pressure relief. I wasn't very sure about this connection but 1 installer and 1 dealer said this would work. There is no other piping coming in or out of that relief valve except the OWB piping.
That smaller diameter copper pipe at the bottom of the oil burner is actually the domestic water feed line to fill/pressurize the system. This is how I back flowed domestic water to my OWB to fill it. This does have a shut off and is currently off.
I don't see anything preventing the OWB from going directing into the oil burner like it is. The only thing I can think of is that the oil burner pressure relief valve is maybe not connected to the oil burner supply/return somehow. I do get hot OWB water from that relief valve if it is opened so Im at a loss.
That smaller diameter copper pipe at the bottom of the oil burner is actually the domestic water feed line to fill/pressurize the system. This is how I back flowed domestic water to my OWB to fill it. This does have a shut off and is currently off.
I don't see anything preventing the OWB from going directing into the oil burner like it is. The only thing I can think of is that the oil burner pressure relief valve is maybe not connected to the oil burner supply/return somehow. I do get hot OWB water from that relief valve if it is opened so Im at a loss.
stee6043
Minister of Fire
My two cents - you're narrowing in on root cause here. I still think you should use the flat plate HX, for the record, but I'd bet right now that you've also got a plumbing issue. Is there any reason you can't tie directly into the system return vs using that pressure relief circuit? Depending on the internal plumbing of your oil boiler that pressure circuit could be absolutely worthless. It may well be preventing any flow from your house. It's also not likely sized correctly (internally) to support the flow rates you need.
Don't buy a new pump. Relocate that return line. And install the HX for long term reliability.
stee6043
Minister of Fire
Worth clarifying - once you install the flat plate HX you'll use the pump from the OWB to constantly circulate through the HX and back to your OWB. The oil boiler circulator will move the water through the house. By installing the flat plate HX you would essentially eliminate the need to relocate that return line. You'll relocate it to the flat plate HX, along with the supply, and all the other plumbing modifications you made become obsolete (for the better).
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