Water Heaters - Flexible or rigid pipes in a new heater self-installation.

Dear Experts:

I have to replace a gas water heater first time in my life, and I was told that alignment of the old pipes with the pipes from the new heater is the biggest problem.

Big stores suggest to use water and gas flexible hoses for self installation. Although, I would still have to solder male endings to the ends of copper pipes, but alignement would be easier. Some people, though, say that flexible hoses will eventually leak. Although, I have no problem replacing a flexible hose, it does not look like a good job.

My questions are:
1. Is it OK to use water and gas flexible hoses for self installation?
2. If it is, do I have to anchor the tank somehow, to prevent its fall?

Many thanks in advance,

Learner
NY State.

P.S.
1. Is it better to use flexible pipes of spiral copper or covered by stainless steel wires? The latter look stronger to an amateur.

2. In addition to dielectric nipples provided by the tank manufacturers, do I have to install dielectric unions between steel of the tank and copper water pipes?

Learner, Welcome to the DIY Forums.
They make flexible water lines for connecting a water heater. They also make the flexible gas line. It is truly easier for the DIYer. I have not heard of them leaking any worse. There is really no reason to anchor the tank. The weight from the water will keep it stable and it will not be top heavy.
Hard-piped looks better and thats why plumbers do it. Good luck.

I assume you are not in California, where flexible gas and water lines are mandatory, as are TWO heavy metal straps, of a design and material certified by the State Architect!

I guess if you had to compare absolutes, then a rigid connection would probably be rated superior. But there are millions of water heaters here connected as I described, and the norm is that the connections last the life of the heater. But that is not 100%; occasionally a minor leak can happen, and you just replace the water line flex. Gas leaks rarely happen unless the connector is subject to mechanical stress or damage.

I would only do it with the stainless steel flex pipes. It's just too hard the other way and I think it looks worse with all those couplings near the end where it's been hacked of several times because the water heater has been replaces so many times.

Dear Experts:

Many thanks for your thoughtful advice. I am determined to use flexible pipes now; however, I changed my mind about copper vs. stainless steel. Looking at the "stainless steel" flexible hoses, I got a feeling that only the wire mesh is stainless. Another customber easily kinked such a hose just to demonstrate me. The salesman does not have a clue of what was inside but said that most people are using spiral copper flexible hoses, so they must be beter. Is it true?

Another thing that surprised me is that the salesman suggested to use compressed fittings instead of soldering male adapters. He said that they are reasonably strong. On the cold water pipe I have a valve soldered close to the place to solder. That can convince me to use 3/4" compression fitting if it is reasonable. The book says that it is acceptable only for M-thickness which I presume it is.

And finally: nobody in the store new what compound to use to fill a 1/4-3/8" gap between a larger hole in a brick wall chimney and the flue pipe.

Such is life of a learner...

Thanks.

I have only seen the copper flex pipes installed. I would go with them.
I do have a question about the water heater flue pipe going into the chimney. What else is this chimney used for? Many areas do not allow the flue pipe to go into the chimney for a furnace because when the water heater is not running, the smoke, gases or whatever comes from the furnace can back down into the water heater flue. Check local code on this.

Copper flex is used by most plumbing installations. They can handle bends much more gracefully than a stainless hose that tends to crimp under the same routing installation. I have seen 3/4 compression used in supply valves and fittings. I have not seen a leak from these yet. If compressed properly why would they?

I have seen way too many pinhole leaks in the braided. The inside liner is vinyl or something. With the reinforcing braid, you will not have a catastrophic blowout, but the pinholes are annoying!

You need to seal the flue penetration with refractory mortar or some other compound rated for this service. A good buillding supply house will have something for you.

I have seen many water heaters installed with copper flex. While it offers an easy install, it does have a drawback. The black washer between the flex and adapter tends to leak. Not right away, but after 5 years or so. It is usually a very slow leak, but it causes a lot of rust on top of the heater. While replacing that washer is no big deal, it is something you should be aware of. For this reason I always use sweat solder copper pipe.

Learning to solder pipe is not as difficult as you think and a propane/mapp gas torch is rather low in cost. Practice on some scrap copper pipe.

Thanks 594tough for your insight on braided. Based on your experience, I will never think about using it. Interestingly, the braided also uses a black washer. Two things to worry about now (the hose and the washer).

Flex gas line is great. Never had a problem with it.

I agree that sweating is the best solution. I have included a link that is interactive on soldering. Even if you decide to go with flex, you will find this interesting.

http://www.doityourself.com/info/h2handlecopper.htm

Dear Experts:

Many thanks for your thoughtful advice. I am not afraid of soldering, I have tools and supplies, but I have two questions about my particular situation.

1. I looked through an earlier discussion where people said that flexible copper hoses (unlike sweat soldered copper pipes) offer dielectric protection in direct connection to steel nipples. I have dielectric steel nipples. Can I directly connect sweat solder copper pipes to them, or I have to use some kind of dielectric connector, or at least some kind of dielectric washer in the basic copper female connector that I am going to screw on the stell nipple?

2. Because of the low position of the shutdown valve on the cold pipe and another pipe that sends some water to the gas furnace or the air blower (I have not figured it out yet), there is a very little distance from the valve to the nipple. All instructions prohibit sweat soldering near the nipples because of plastic inserts and dip pipe, but they do not say how near. I will pre-solder about 2-inch pipe to the female socket but the end of the pipe has to be soldered in with the socket tightened to the nipple. Can I solder 2-3 inches away from the nipple, or the heat can damage it? It will also be about 3 inches from the valve with water, so I might have to drain the whole system to stay further from the water. I can certainly, resolder the valve and another pipe to a higher position but that escalation pushes me to go with a flexible pipe and do not bother.

Many thanks again,

Learner.

soldered adapter to connect the nipple of water heaters, does that
invalidate the dielectric effect of the nipple? I thought the soldered
adapter does not seal with the plastic insert of the nipples, rather it
seals with the iron thread of the nipples, correct?

Thanks,

SZ


I have seen many water heaters installed with copper flex. While it offers an easy install, it does have a drawback. The black washer between the flex and adapter tends to leak. Not right away, but after 5 years or so. It is usually a very slow leak, but it causes a lot of rust on top of the heater. While replacing that washer is no big deal, it is something you should be aware of. For this reason I always use sweat solder copper pipe.

Learning to solder pipe is not as difficult as you think and a propane/mapp gas torch is rather low in cost. Practice on some scrap copper pipe.

Thanks 594tough for your insight on braided. Based on your experience, I will never think about using it. Interestingly, the braided also uses a black washer. Two things to worry about now (the hose and the washer).

Flex gas line is great. Never had a problem with it.