Replacing old water heater

[user 32496]

So...I have to replace my 19 year old electric water heater ASAP since it started leaking yesterday. I can't believe it only lasted 19 years! The old one is a Bradford White 50gal, 4500 kWh heater with a serial number starting with B. Bradford White says that indicates a 2005 model.

It currently doesn't have an expansion tank so I need to add one. I've heard all kinds of things about the position requirements for the expansion tank so I thought I'd put it out here for expert advise. I have checked the installation instructions on two different expansion tanks and they show a picture of the tank installed with the water on top and the air on the bottom but the Zurn model says this:

INSTALLATION
5. Strapping or bracing must be used when tank is installed in the horizontal position. This will allow support of the tank when filled with water.

So, does it matter what the orientation of the tank is?

Also, the current setup has cpvc attached directly to the input and output of the heater. I seem to remember hearing that an 18" metal piping is required between the water heater and plastic pipe however I don't see that in the IPC code. Chapter 5 simply says:
SECTION 503

CONNECTIONS
503.1 Cold water line valve. The cold water branch line
from the main water supply line to each hot water storage
tank or water heater shall be provided with a valve, located
near the equipment and serving only the hot water storage
tank or water heater.

I found this picture on-line where the installer just tee'd right out of the heater and installed the expansion tank upside-down right on top. Is that acceptable?


Here's the current setup...

 

[user 32496]

Does anyone have experience or comments about either of these heaters for a replacement?

This one is closest to me


This one is slightly cheaper

 

[Twowaxhack]

Basically the same. They all leak at some point, and I’ve seen all brands leak on day one and all brands that have lasted over 20 yrs.

Expansion tank goes on cold side in any orientation you want.

Some codes allow plastic straight to electric heaters. Some don’t.

Replace your relief valve piping to full 3/4 size and don’t use flex lines or soft copper.

 

[user 32496]

Thanks! I was hoping @Twowaxhack was on duty today!

 

[havasu]

Yeah, it is nice to get an expert's opinion on things. I wish our other experts would chime in more often. They are all a wealth of knowledge!

 

[RS]

If you're getting by without an expansion tank, why do you need one now? If you're on a municipal water system you need one, if on your own well you don't, the well pressure tank is an expansion tank. Unless there is something I didn't think of! We have never had one, but we have always been on a well with a large pressure tank.

 

[havasu]

Honestly, we are on municipal water here, and I have never seen an expansion tank in my 68 years of living in this area.

 

[RS]

If there isn't a check valve in the system you don't need one, but I assumed all water meters or prv's have a check valve, to prevent a homeowner from contaminating the municipal system by somehow back feeding. It has happened!

 

[Twowaxhack]

There are several reasons why a system could/would need an expansion tank.

All being a closed system, on city water or well water.

 

[RS]

Further explanation needed! If you have well with a pressure tank, wouldn't that take the place of a expansion tank? It always has for me.

 

[Twowaxhack]

Further explanation needed! If you have well with a pressure tank, wouldn't that take the place of a expansion tank? It always has for me.

Not every plumbing system is the same. There are several ways to have a closed system.

 

[user 32496]

We are on Municipal water. Originally, there was a pump and well (which is still here) but at some point municipal water became available. I assume there is a check valve on the meter or near it.

I see a shut off valve, a meter, and a pressure regulator. One of them may act as a check valve, I don't know.




When we lived in Sacramento area, our house was built in 1989 and had a gas water heater, on city water, with no expansion tank. I had the water heater professionally replaced in around 2005 and no expansion tank was installed at that time.

I understand the reasoning behind the expansion tank though. They are cheap and easy to install, so.... I bought a 2 gallon expansion tank and a bracket to hang it on the wall. I also bought two 18" stainless steel lines to go between the heater and my house connections. I don't see that requirement in the IPS code book but it seems like a good idea. My old heater didn't have a pan under it either. I'll add that but there is really no good way to hook the pan to a drain. Code says if I am replacing an old heater that didn't have a pan and a drain, I don't have to hook the new pan to a drain.

 

[Twowaxhack]

Some PRV’s have a bypass feature that will allow backflow but depending on what the unregulated pressure of the city line, that unregulated pressure may exceed the maximum allowed ( above 80 ) and the bypass feature becomes useless.

I’m going to say based off the pics that you most likely do need an expansion tank.

 

[user 32496]

Well…I finally finished the water heater installation. Thank you to everyone’s wonderful suggestions!

I had the luxury of time because, most of our house, is served by a tankless heater but the water heater that I replaced is only used for the clothes washer and one bathroom that doesn’t get used much.

I really wanted to clean up the plumbing around the WH so I ended up cutting into the wall behind it. The utility room, where this WH is, was added on at some point in time, so the wall behind the heater used to be an exterior wall.



The Pex coming down from the attic is there because the old, original galvanized pipe that came from the main house, broke under the slab. I just bypassed it through the attic.



Besides the connection to the house through the attic, there are also old CPVC pipes that connect the WH to the washer and also the bathroom on the other side of the wall. I found that the old CPVC is a little brittle so I carefully cut it with a Dremel style tool. (Notice, the hot is the blue pipe and the cold is red).



I used sharkbite elbows to transition from the CPVC to the Pex and ran the Pex upward inside the wall. The CPVC originally came out of the wall here and ran up the outside of the wall to the WH.

I added an electric shutoff switch (per code) and two 18” flexible stainless connectors between the tank and the new plumbing.



I decided to hang my expansion tank with the water on the bottom and the air on top. I just feel better with the water on the bottom, however, I realize that if I have to change out the expansion tank, it will be a mess.

I used two dog-eared Pex to Female pipe thread elbows, screwed into the wall, to make my connections sturdy.



I put a pan under the WH although there is not a good way to hook the pan to a drain.



That white pipe to the right of the WH is a dip-tube I bought for the old WH but it wasn’t needed and so I never installed it.

I was thinking about how to get rid of the old WH and Ruby says, “I’ll just put it on FB MarketPlace for free. It will be gone in no time!”

I thought, who would want an old WH that leaks? I told Ruby to be sure to state that it leaks in the FB Market post and she did. We had 15 people within minutes that wanted it. The first guy was a flake so she went with the #2 guy and he came out the next morning and picked it up. I didn’t get to ask him what he was going to do with it though.

 

[havasu]

They can easily get $20 from a metal recycling company.

 

[pasadena_commut]

Where does the pipe on the temperature/pressure relief valve go?

 

[user 32496]

Where does the pipe on the temperature/pressure relief valve go?

I have it tucked into the pan which I know is not ideal but that’s where it is.

 

[GReynolds929]

I would highly recommend painting or covering the exposed PEX to protect from UV damage.

 

[user 32496]

I would highly recommend painting or covering the exposed PEX to protect from UV damage.

Good idea! Thanks!

 

[pasadena_commut]

I have it tucked into the pan which I know is not ideal but that’s where it is.

Not an expert, but I believe the code says it must discharge through an air gap in the same room as the heater, typically it would be right next to that heater.

I kind of doubt that most drain pans would actually be able to handle the flow from an open TPR valve without either overflowing or splashing over the side. Yet another good reason to put the water heater in the garage (or some basements) where the concrete floor isn't going to be damaged by the water.