And yet another heating question/problem.

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urhstry

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I have my water set at 180 degrees on my Ranco at the OWB. The temp on the thermometer in my house on the OWB side of the HX is 180. Zero loss. HOWEVER, the other side of my HX which is the heating loop for my home never gets to the 180 temp and barely gets to 165. This is without anything on and just having the water circulate through the loop without a fan on the exchanger for the hot air heat. Is this correct? And of course the other issue I am having is that when two zones call for heat, the water loop temp drops to somewhere in the 130 range even though the OWB side can keep up. What am i doing wrong or what needs to be changed?
 
seems like an unusual heat loss.

does the water flow good? ie: no blockage in the HX?
 
The entire set-up is only two years old but I can''t say for sure if there is any sort of blockage. How can I tell?
 
The hot water from the OWB should go in the top (or downstream air side) of the HX. Then the air crossing over it does not get cooled as it passes over the next series of tubes.

Not sure why such a drop with no load. Are you measuring it with the same thermometer in a similar fashion? I don't really have a feel for how much mine drops when it calls for heat - 130 may be acceptable.
 
is your pump big enough to circulate the h2o quick enough. Not sure. I put a bigger pump in and am using less wood this year and it colder out....
 
This is a new problem but only after revising my system. I changed from a Taco 009 to a Grundfos 15 pump on high speed. The system works well when its in the 30's and higher but it just can't make the heat in the cold weather we are having in PA. This pump takes the return water and pumps it back into the HX and then into an oil burner where it can circulate in the house as needed.
I have a thermometer plumbed into both sides of the HX to see the temps. Taking away all other parameters, why, with no load, would the water not be able to match itself on both sides of the HX?
 
You could try switching sensors/thermometers to see if one is out of calibration - you know if you're making heat in the HX then it's the sensors! Hopefully you have valves to shut off so you can make the swap easily.
 
Problem is definitely not with the thermometers. The air coming out of the floor registers is lukewarm at best. I am not even sure what to try. It won't come up to temp as it should.... doesn't make sense.
 
You said you changed pumps. Have you checked to make sure you don't have any air in the plumbing after the work? These little curculating pumps don't self prime and can't even make enough pressure to push a very big slug of air through the system and back to the furnace.
 
Now that is something I didn't do.. or know about. How exactly would I go about doing that? Lines come out of the boiler to the pump, through the HX, back into the manifold of return lines into the boiler. Once I turned the pump on, I could hear bubbling in the oil burner tank.
 
You said you changed pumps. Have you checked to make sure you don't have any air in the plumbing after the work? These little curculating pumps don't self prime and can't even make enough pressure to push a very big slug of air through the system and back to the furnace.

good call.....he could have an air lock in the HX allowing only a little bit of water to pass.

i don't have an OWB, but isn't there a way to check water circulation at the stove return line?

would there be a way to flush the lines with a garden hose?

i've done that with my gas boiler system when i've had to work on it to get all the air out of the lines.
 
I have wye strainers at both sides of the HX.. if I unscrew the cap off, it should bleed the air out if there is any there... going to try that now.
 
I can't find air in any part of the system... I shut everything down and let the OWB hang at 190 while the other side of the HX came up to about 180. It didn't seem to want to go any higher and the temp dropped to 64 in my house so I turned the system back on and it is s-l-o-w-l-y coming back up to 70 and the HX loop temp is at 155-160.
 
The hot water from the OWB should go in the top (or downstream air side) of the HX. Then the air crossing over it does not get cooled as it passes over the next series of tubes.

Not sure why such a drop with no load. Are you measuring it with the same thermometer in a similar fashion? I don't really have a feel for how much mine drops when it calls for heat - 130 may be acceptable.

Correct me if I'm wrong,but the water from the boiler should enter the bottom port of the water to air heat exchanger,flow through the exchanger then out the topmost port. The same applies to a water to water exchanger. Scott
 
Let me clarify.. I am talking about a water to water heat exchanger in order to keep the OWB system separate from the oil burner water. My hot air heat is supplied by a line coming off the oil burner to a water to air HX that lays flat across my central A/C.
 
Correct me if I'm wrong,but the water from the boiler should enter the bottom port of the water to air heat exchanger,flow through the exchanger then out the topmost port. The same applies to a water to water exchanger. Scott

My hot water from the OWB goes in to the top of my water to air exchanger and comes out the bottom. When the cool air flows over the exchanger it's pre warmed by my lower coils and super heated by the top that goes in to my ducts. I have a 009 pump on my system and have a loss of 10 degrees through my exchanger with the fan going. My garage has a 007 pump and set up the same way. When the fan is off, I see no real heat loss if any.

I would think that your coil must have air in it. You say that you can hear the bubbles. You shouldn't hear anything in your lines. On the older cars, if the heater core was air locked, the one heater hose would be hot going in to the coil and cold / warm going out. Can you back flush your system with water and push the air back in to the OWB? In reality, those little pumps can not force out the air. They were not made to push water like we think. Can you remove the return line from your exchanger to make sure you have a flow of water? If it worked before it should work now. I doubt the exchanger would be plugged that fast.
 
On my plate to plate exchanger I have the hot water from my OWB going in at the top of one side and out the bottom. The water going from the boiler should go in at the bottom on the other side and out the top. Again, the water is pre-heated and gets hotter as it goes out. Again, these can air lock so check for air. You must have a 30 plate exchanger or better so chances are it shouldn't be clogged yet. Your pump could be air lock and gravity is heating your lines so check your pump also. My first 007 pump was new and the impeller was stuck so my lines still heated going in but cool to the touch on the way out of the exchangers.

Air in the system is the biggest thing to cause trouble
 
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I am starting to believe that this could be my problem.... I know how to get the air out of my oil burner lines but the W2W HX is a soldered loop with no breaks to get at... same for the HX over my A/C unit.... I don't know enough about HVAC to know what to try first.
 
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