urhstry
ArboristSite Operative
Anybody have any ideas how to diagnose this or hoe to check for air?
And yet another heating question/problem.
- Thread starter urhstry
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It sure sounds like you are air locked after you changed the pump. Like the others have said this pumps air lock easy. You are going to have to open the line up and see if you are getting flow or not. I have a pump set up that I hook up to my system and then I force liquid threw the lines and have T;s solder in at the heat exchangers with ball valves on them so I can bled the air out of the lines as I run the pump. I have four lines running to my house each one is 360 ft long and I had a hard time getting the air out of the system when I first set it up.
I think I understand your system now - the OWB just heats the water in the oil burner system with a water to water HX then that water flows through the water to air HX in the hot air furnace ducting.
What is the temp of the OWB circuit going in and out of the W2W HX? And the temp of the oil burner circuit in and out? The oil burner circuit temp will probably never equal the OWB circuit if that's what you are after even under no load (losses in heat transfer/lines/volume of water in system/etc.) I don't know if that's what you were measuring before the pump change.
If there is air in the system you may be able to loosen a fitting downstream from the W2W HX until the air escapes. The pump can't push a bubble of air all the way back down the return line to the OWB but should be able to burp if you can crack a closer joint. Be prepared for a little water on the floor.
The W2W HX could have deposits restricting flow also. Might have to remove a line to check flow. More water on the floor.
Is there a speed control on the Grundfos 15 pump? Is it possible it's moving water too fast on high speed to get enough heat transfer? Do you have a back-up pump you can swap to eliminate the pump as being defective?
Hope you can find it - most of us know how frustrating it can be not to find the cause to a problem right away.
What is the temp of the OWB circuit going in and out of the W2W HX? And the temp of the oil burner circuit in and out? The oil burner circuit temp will probably never equal the OWB circuit if that's what you are after even under no load (losses in heat transfer/lines/volume of water in system/etc.) I don't know if that's what you were measuring before the pump change.
If there is air in the system you may be able to loosen a fitting downstream from the W2W HX until the air escapes. The pump can't push a bubble of air all the way back down the return line to the OWB but should be able to burp if you can crack a closer joint. Be prepared for a little water on the floor.
The W2W HX could have deposits restricting flow also. Might have to remove a line to check flow. More water on the floor.
Is there a speed control on the Grundfos 15 pump? Is it possible it's moving water too fast on high speed to get enough heat transfer? Do you have a back-up pump you can swap to eliminate the pump as being defective?
Hope you can find it - most of us know how frustrating it can be not to find the cause to a problem right away.
I thought the water from the outside unit should circulate all the time? And the way he has it set up, the inside unit should circulate all the time through the w/w hx so the inside unit is always up to temp? Is the w/w hx large enough?
you may have to bleed air off at the hights point, where ever that may be.
you may have to bleed air off at the hights point, where ever that may be.
urhstry
ArboristSite Operative
applefarmer
ArboristSite Operative
If you can hear water flowing you have air in your lines. The best way I have found to get it out is to restrict the flow after the hx with a valve. I don't completly close it but restrict it to force the air threw the hx. If you don't have a valve, I would install one after the hx then simply repair the line. It is simple to do with sharkbite fittings. Hope this helps.
