Help with water heater

[oxmanwi]

So I just replaced my old water heater with a new unit. My question is, on the cold and hot water connections what to I use to make a leak free seal? I thought using Teflon tape would be good enough, but I was wrong. I have a small pin hole leak which drips every 2 minutes on both sides so I have to redo my copper soldering.

Thanks in advance!

Josh

Pictures:

 

[rlitman]

Threaded copper fittings have this issue. It's partly the nature of the threaded copper, and partly the fact that you sweated the fitting after screwing it tight. That heat relaxes the teflon and loosens the joint, leading to a leak.

First, you should sweat a stub of pipe onto the threaded fitting BEFORE screwing the fitting to the water heater. This will allow you to screw the fitting on cold, and not heat the threaded part with a torch afterwards.

Second, threaded copper fittings require a surprising amount of torque. Their threads need to be seated quite tightly to seal.

Third, because of the poor fitting threads on a threaded copper fitting, I like to do a belt and suspenders approach when it comes to tape. I'll apply a VERY light coating of dope to the root of the male threads. Then I'll wrap the male end in pink (extra thick teflon tape; do not use white tape here, but blue or the new thick grey stuff is fine too). Finally, another light coating of pipe dope (Rectorseal 5 is my dope of choice). Then screw it all together VERY tight and don't heat it after assembly.

 

[mach158]

Installing flex lines are a good idea to prevent the resolder issue. Also I use teflon tape and usually have no problems. I know some prefer the paste.

Sent from my SM-G900R4 using Tapatalk

 

[homebuilt burner]

If you are taking it apart to reseal. I would cut the copper pipe up about a foot, then use a coupler soldered onto the pipe that goes onto the h2o heater. I use tape and past together, tighten with a wrench. Then go back and solder the top of the coupler so the heat is away from the threaded connection. And cool it right away after soldering with a wet rag. I have had good luck with this process.

 

[toyotadriver]

I have had all kinds of problems with threaded copper. I never have any problems with my sweated joints but I frequently can't get copper threaded joints (male and female) to not leak. I think it's the cheap copper pipe fittings that are on the market.

I never have problems with PVC threaded fittings but have had endless problems with copper threaded fittings. I have not had sealing issues when connecting a gasketed threaded flex pipe to a copper fitting mainly because of the way it seals....rubber gasket vs relying on the threads to do the sealing.

I would replace those with flex stainless pipe. It's not expensive and works great. It'll also seal the first time.

 

[Orangestang]

I'd cut that off close to the heater, go buy some unions the right size ,thread those on the heater and sweat the copper to the other side of the union.

 

[csp]

Use this type of flex fitting. These are required by most local building departments in my area due to the shrinking/swelling soils found on the front range of Colorado.

 

[captain14]

Saving this one

 

[md21722]

I second the unions, or use the flexible hoses available today. If you don't have ball valve disconnects now is a good time to install those too. In some areas changing a water heater requires a city inspection.

 

[Muzzy]

Had the exact same problem when I installed my water heater, only I got sick of taking it apart and putting it back together at the union....cause you know the copper unions I bought at lowes dripped too for a bit.

With a drip every couple of minutes, leave it for a week and see if it seals itself.

 

[59 wagon man]

2 copper sweat unions and a good teflon tape

 

[zmaxmotorsports]

Threaded copper fittings have this issue. It's partly the nature of the threaded copper, and partly the fact that you sweated the fitting after screwing it tight. That heat relaxes the teflon and loosens the joint, leading to a leak.

First, you should sweat a stub of pipe onto the threaded fitting BEFORE screwing the fitting to the water heater. This will allow you to screw the fitting on cold, and not heat the threaded part with a torch afterwards.

Second, threaded copper fittings require a surprising amount of torque. Their threads need to be seated quite tightly to seal.

Third, because of the poor fitting threads on a threaded copper fitting, I like to do a belt and suspenders approach when it comes to tape. I'll apply a VERY light coating of dope to the root of the male threads. Then I'll wrap the male end in pink (extra thick teflon tape; do not use white tape here, but blue or the new thick grey stuff is fine too). Finally, another light coating of pipe dope (Rectorseal 5 is my dope of choice). Then screw it all together VERY tight and don't heat it after assembly.

 

[zmaxmotorsports]

Get yourself a slip coupling,Tighten the fitting tighter then sweat the reair coupling.
Or do like I do and eliminate those damn galvanized ******* and just sweat a male adapter on to the copper and rector seal them really good,Then tighten the $hit out of them.