PVC from secondary pan

I’m taking an AHIT course and they said you cannot use PVC as a water heater pan drain pipe. Is this correct? It seems the pans you buy at Lowes and Home Depot have PVC fittings already attached to them.

No, not that I know of.

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pvc is not a listed w/h drain pan material
that being said most ahj turn a blind eye/ignore the written word
i continue reporting & let the chips fall
pan & drain


You must be reading the curriculum incorrectly. PVC is approved as a drain pipe from the water heater pan. It cannot be used in the TPRV discharge pipe.

Post the section of your curriculum you are referring to instead of a blind statement.

He read it correctly, the pan’s drain must be that of materials approved for water distribution because of the temperature. You can use CPVC but not PVC.

PS: check the image he posted, it’s right in it

I’m taking an AHIT online course to prepare for the NHIE. They used the image I posted above and then specifically said PVC cannot be used for either the TPR drain piping or the pan drain piping.

Where are you located?

Can you post from current UPC or IPC code?

I live in Georgia (IPC), but the course I’m taking is not a state-specific course.

The code was already posted by none other than Barry :slight_smile:

504.7.1 Pan Size and Drain
refer to table 605.4 of IPC


Table 605.4 in IPC. This table is for piping approved for potable water distribution so yes this is correct.

Will the PVC the CPVC drain is ran to be able to withstand those temperatures?

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I haven’t, personally, tested the theory to see how well it would work under different scenarios… but I believe it would be able to “better”, yes. It, obviously, would depend on many different things… like how long is the pan’s drain, how well is it supported, how long does the discharge last, etc… It’s not a big deal IMO, but the code does make sense. If you disagree with the code, you can submit a recommendation to the panel that agreed on it :slight_smile:

So, you can’t drain a water heater into a PVC floor drain either then?!

Start recommending all house drains that handle a hot water source connected to a water heater be CPVC or better yet, copper!

Yea, water at the heater is 120F to start but not after it drains into the pan from a small leak.

Desecration is the greater part of valor people. Try using some.
As Badair said, just note it and leave it at that. No recommendation for a Fluid Dynamics Engineer to evaluate further required…