Speaking of PEX...

I went to a realtor’s open house this week and stumbled across a whole (small) subdivision where every home is being piped with PEX. I don’t have an inspection there yet, but would like to know what to look for in such a system. TIA


Most completed homes will have very little of it visible unless it has a crawlspace or unfinished basement.

Look for pipe ends at fittings that are not cut off squarely, this causes the crimp ring to be too far from the fitting where the crimp force is on the very edge of the barbed end.

Look for the fittings that have QPEX stamped on them.
See www.zurnclassaction.com for info and search on here for QPEX or Zurn.

Be careful, the ones stamped with DPEX are not an issue. These are Durapex.
The D and Q do not look all that different on the fittings at some angles.

Also look for the typical installation errors, clamps too tight or pipe bent to sharply or damaged. PEX should have isolation where it passes through concrete.

Pex is not rated for TPR valve piping but allowed in many areas.

A local builder had some leaking issues that they traced back to the plumbers crimp tool being out of calibration. The plumber would have found the problem if he used the Go-No Go tool to check the crimps to see if they were the correct diameter (not too small and not too large).
Over crimping can crack the brass fitting.

I helped a plumber find a leak on a new home one day, a pex pipe was dripping some water with no visible damage at all. He replaced a six foot section and the leak was gone. Very strange problem, manuf. defect or maybe the pipe had been exposed to too much sunlight or over stressed during the pressure test.

I called a manufacturer a couple of months ago when I found it being used for a TPR, and they said it was rated for that use, and it was fine.

I was in a home last week that was plumbed with HePex. It has fittings when you swell the end, and has compression fit with plastic rings. None of the fittings had plastic rings on them…I suspect there will be some issues in the very near future.

Not necessarily, The PEX has a physical memory, and expanding it to fit over a fitting is all that may be necessary, dependng on the fitting.
That being said, there are too many types of fittings on pex, this creates confusion to anyone not doing it on a daily basis.

PEX is not approved for the T&P valve.It does not meet the temperature requirement ,the fittings reduce the size of the pipe.Check your code book.Ed Willis

According to the manufacture whom I spoke to on the phone, it does.

If you look at the PEX pipe it will have a 180 deg. temp rating stamped on it. Last I checked water would be well above 180 before the TPRV popped. Code says it must be temperature rated and non reducing, PEX can do neither.

would a letter from the manuf, eliminate any responsability/confusion regarding allowingTPR drain or would more likely fall under AHJ

No, manufacturer would have to pay for the testing to have it listed