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Discussion Starter · #1 ·
I have a customer that has called my company to try and explain why a hot water coil burst in cooling season(it burst at all the utubes on back side like it froze). The management company put new coil in and it burst in 2 days. This is a hot water coil that used a water heater to supply hot water. Of course they think by me installing it it will work. My concern is it will happen again. My thoughts are it is getting to much pressure and to hot. There is a pressure expainsion valve assembly that releives pressure on system on domestic side after tempering valve, but nothing on heating side(it is like this on all units). It is fed with cpvc 3/4". When i install the new coil i was going to replace relief valve on expansion valve assembly, put pressure gauage on pipe feeding the coil and monitor temp to see if water heater tstat is out of wack. He has had couple others burst as well. My orginal thought bad batch of coils. Any ideas?
 

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Discussion Starter · #3 ·
it is a heating hot water coil and i cant see any reason why it would freeze unit is inside apartment and has not been below freezing
 

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Good question!

I have a apartment complex I do work for and I have had that senerio happen in the heating season primarily but occasionally in the summer, the tenant in the apartment in the winter will turn the hot water heater up all the way which obviously increases temperature and pressure but most of these set ups don't have expansion tanks which leaves the system with no buffer. I have started putting a expansion tank in and so far has resolved the problem.

Good luck!
 

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Discussion Starter · #5 ·
well changed coil today installed pressure gauge on system to see what was happenning and also put what they call expansion valve with 100psi relief on it on heating side of system the one that is in system now is on incoming cold water. Is this right? Anyway after running system it is running 75 average psi and i adjusted water temp to 140. System pressure did not change much while tank heated up or down. I guess time will tell if it holds. I did find the tsat stuck with cooling on all the time and would not shut off wondering if ac unit could get the hot water coil down to freezing temp it would have to run for a bit before that would happen so don't think that could happen but coil did have freezing type damage
 

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Discussion Starter · #6 ·
well coil has not busted so i think i am safe. After i changed coil they asked me to check a/c out to make sure it was working. I found that the a/c condenser wouldn't shut off from tsat. So i changed the tstat out and i do believe how ever unlikely that this was cause of coil busting after talking to the building guy i found that they had issue with this system before. I guess info would be nice up front. So hopefully problem solved:thumbsup:
 

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I hope your problem is solve as they find out there is an issue regarding the system, let us know once its solve. Good luck
 
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