anybody swapped out their heat exchanger? I'm wondering if replacing the one my installer recommend for my house would give me more heat and and help me have a better system. Background: I have a Hardy H4 for a 3000 sq. ft. Two story very old house. We have a minimal amount of insulation. I'm getting set to add additional blown in cellulose to what we have in the attic. We have batts retrofitted under the crawl space. Wall insulation in only a few walls where I have replaced siding. Setup of the system as a split system with two thermostats and two separate pumps. No domestic water being heated. Pipes insulated and in a 4" pvc pipe 2 feet underground. Goes 70 feet to the house. Wierd thing about my setup, after it was first installed it didn't work very well at all. I had the installer back out and he flushed the heat exchanger. He said it was full of red mud....we have red clay where I live. How does that happen unless clay got scooped into the pipes when they were first installed? Anyway, how difficult is it to swap out a heat exchanger? What is entailed in doing the job? I have pretty good diy skills.
Shouldn't be that hard to change. Depending on the size difference you may need to do some sheet metal fab. Then hook up your pex to the new heat exchanger.
Measure temps leaving the boiler, arriving at heat exchanger, leaving heat exchanger, and arriving back to boiler. Compare to see where you are losing heat. Also measure house side in and out of heat exchanger to see how much btus is actually getting transferred. Clay in system would come from being sloppy when running pipes as you suggested. Changing exchanger wont be bad. Put in a wye strainer so you dont mess up the new one. Matter of fact, i would try removing and flushing the current one before replacing. But i am guessing you dont have much time now, lol. Check your circs also to make sure no dirt there. Again, wye strainers!
I don't have a boiler but have many years experience in the HVAC field and can say that depending on where the heat xchanger is (Ease of access) it shouldn't be a difficult swap. The biggest issue will most likely be that you will have to make some new sheet metal pieces to adapt to your duct work since the new heat exchanger will most likely be larger
The red 'mud' could be settled rust. As far as the heat exchanger, is it water to air or water to water?
Thats a good point about rust. Especially since it is an open system, of which i kno little about except ur supposed to use some sort of water treatment and have it tested periodically.
Thanks for your replies. I'm pretty sure it was actually Red clay mud from the initial install. plus the Hardy is all stainless steel so I don't think it could rust, maybe? The heat exchanger is water to air that exists through our central heat and air system.
L Good ideas. I'll check on those temps with a digital temp. gun I have. Last year I emptied the entire stove and replaced the water after I recirculated it. Just making sure it was fairly clean. I was just thinking of replacing the heat exchanger to gain more heat output.
Just make sure when using the IR temp gun you are using it on a surface that will give you accurate readings. Trying to use it on copper or brass will give you all kinds of crazy results. If you have to, you can hit a small area with some flat black paint to help. As coal reaper said, it is very important to check those temperatures both for btu loss in your underground pipe and btu transfer in your heat ex changer. If you know your temperature drop and your GPM flow than you can easily figure out how many btu's are being used.
