Overcoming Excessive Loop Lengths

R Mannino

I know a few of you out there have discussed this problem before. It's just my memory is not what it used to be. How did you "overcome" the problem of excessive loop lengths of pex tubing? I can't recall the exact details but I do remember some of the cures were creative to say the least.



Ron

1pipe

1 pipe

I had a problem with a 600' loop that a general contractor had installed not adhering to the 350" 12" PEX limit.  I was going to install an additional pump on the far side of the loop so I would have one pushing and one pulling which I though would solve the problem.  I never did it in the end though.  I ended up designing it to run for a much longer period of time instead.  If you do that the end of a long loop does eventually come up to temperature.  I think my idea of the pumps at both end would work though.



Tom Friel SF CA

NRT_Rob

several options

1. increase water temperature, to make the average temperature what you need it to be, while not overheating your media (such as, don't go over 140 in concrete) or that section of floor. temp might not be even across the loop but it may not be that bad.



2. more pump. a second pump in line (flange to flange) will double your head at the same flow. might still be inadequate depending on the loop length and flow requirements.



3. If neither of the above two can do it, you can try a 4 way valve to reverse flow through the loop (on a timer) to heat up each end over time, but that's an expensive and more complicated fix.

R Mannino

Thanks Guys

Just trying to help out a friend.