Shared Knowledge

"Rheem Gas Hot Water Heater Leaking at Bottom - Do-it-Yourself (DIY) Fix"

19 September 2011


Summary: in my case, Rheem used a plastic water drain valve that was the cause of the leak. DIY repair if you have the tools.




RheemGlas Model 21V75 natural gas water heater.

RheemGlas means metal tank has a porcelain-enamel lining.

Bought new in 1991.

75 gallon model.

Started seep, leak, at bottom, towards front or where thermostat is located, around one "foot."

First thought was, given age of water heater, time for replacement but new, similar, Rheem almost $1200 and then there is install hassle or cost.

As weakest part of water heater water containment is around any water tank penetration, looked at hot water out, cold water in and finally tank drain valve.

Could feel and then see, water seep from around tank drain valve.

Perhaps a simple tightening of drain valve into tank would cure problem?


Plastic drain valve:

Tighten drain valve into tank....take monkey wrench and begin to turn clockwise on drain valve.

Pop goes the Wessel!

Drain valve was plastic (why didn't I notice?) and with not even a strong torque, busted clean off and water shot out everywhere.

Quickly turn off cold water inlet valve.

Quickly turn water heater thermostat to "off" and then turn off all natural gas to the heater via the gas cock valve.

So after 75 gallons bucketed to nearby toilet and floor cleaned....


Do-it-yourself (DIY) fix:

Inspected hole in tank for drain valve and was threaded but had left-over plastic drain valve stuck in threads.

Using a rubber mallet and small flat blade screwdrivers, carefully managed to get hunks of old valve out of hole.

Appeared threads in tank were good so wondered if standard size and thread??? No idea.

Took what is left of old tank drain valve and headed to Home Depot.

Determined I need male, 3/4inch drain valve and finally settle on Camco "water heater" drain valve because it has extra long threading.

Expect threads in tank to be rough because of old plastic valve and thus hand thread new Camco slowly into hole.

Use monkey wrench and tighten new Camco another complete turn..

Take new Camco drain valve back out of tank.

Insert Camco into hole again and tight it in.

Take Camco out of hole.

Now using Teflon pipe tape, wrap tape around Camco drain valve threads.



Make 6 complete Teflon tape turns around Camco drain valve threads.

Now hand thread Camco back into Rheem tank drain hole and then use monkey wrench to slowly tighten.

As extra long threads on Camco, tighten drain valve further into tank than I have gone on previous thread-cleaning insertions and withdrawals.

Making sure Camco drain valve is closed (flat blade screwdriver), I turn on cold water fill valve.

Go around to all faucets in house and open to let air bleed out of hot water line as tank fills.

Tank eventually fills and no more air being released from faucets, so shut down all faucets and let water heater sit.

No obvious leak on floor anymore.

Turn natural gas cock valve to "on" or to allow natural gas to the water heater and then light the pilot light.

Once pilot light lit and stays lit, turn heater thermostat to warm and burner fires up.

After water reaches desired temperature, check water at faucets and ok.

Check around water heater and no leak.

We will see.

Only time will tell now but sure drain faucet/valve on water heater not going to pop off every again.

Oh, and black cap shown in picture of new, installed, drain valve is for "insurance". Should the actual valve portion begin to leak or try to leak, the black cap keeps it from leaking on the floor.


Ron - Shared Knowledge Home