Aww, Poor Wadda Heater Go BOOM!!!

[hausdok]

It's always fun to re-post this every once in a while.

Unvented Cylinder Explodes

[Mark P]

So who recommends to customers they test the TPRV once a year?

[hausdok]

Not me,

Others might do it and might have had better luck, but the last time I did that, which was about two months after I first got into the business in 1996, the customer asked me to show him how to test it. Like an idiot, I complied and the thing refused to shut off and continued to piddle, and piddle, and piddle. After the inspection and a trip down to the local Ace Hardware and then a trip back to the house to replace the valve, I decided that I'd let them read their water heater manual instead. Now I tell them to drain the crud out occasionally, change the anode rod, and follow the other instructions contained in the manual for the water heater - which includes the manufacturer's recommendation about testing T & P valves.

Yeah, yeah, I suppose I could have used a peckism and declared, "See, it failed under testing," so I wouldn't have had to pay for it, but that really isn't a test anyway, all it proves is that the valve isn't stuck, not that it will open when it's supposed to at 150 lbs of pressure or at 210°F as it's supposed to.

You need to eat more, Mark. You're looking a little haggard.

OT - OF!!!

M.

[msteger]

I don't make that recommendation to my clients, and I do note in the report that I do NOT test the valve and mention that doing so can often cause it to leak, like the post above mentioned.

[Bob White]

From Rheem's generic Use and Care Manual for residential electric water heaters:

"At least once a year, lift and release the

lever handle on the temperature pressure

relief valve, located near the top of the

water heater, to make certain the valve

operates freely. Allow several gallons to

flush through the discharge line to an open drain."

From a typical Rheem gas water heater user's manual:

"At least once a year, lift and release the

lever handle on the temperature pressure

relief valve, located near the top of the

water heater, to make certain the valve

operates freely. Allow several gallons to

flush through the discharge line to an open

drain.

NOTICE: If the temperature and

pressure relief valve on the hot water

heater discharges periodically, this may

be due to thermal expansion in a closed

water system. Contact the water

supplier or your plumbing contractor on

how to correct this. DO NOT plug the

relief valve outlet."

I exercise every TPR valve that isn't frozen shut (unless it discharges in a way that can damage something). I've left a few of them dribbling with a note to the homeowners to replace them (it helps to attach the note to the "routine maintenance" section of their water heater manual.) No callbacks from angry or litigious homeowners yet --- over TPR valves, anyway.

Most of the "leakers" tend to slowly shut (or the rust/corrosion seals again) after ten or fifteen minutes, though. On these, I recommend replacement in the report.

I do not consistently recommend exercising the valve in my report, though I usually talk about those things either during or at the end of the inspection.