Plumbing – Legal water heater replacement


I'm looking to replace my water heater. I currently have a 15 year old 40 gallon gas water heater, and it's time to go. I had several quotes from local plumbers, and choked at the prices. I'm going to go with a 50 gallon Rheem from Home Depot, and am going to do it myself, and I want to do it legally, to code, and inspected.

I have a good deal of experience with plumbing and electrical installation (copper pipe soldering, 110V and 220V electrical, etc), and want to do this the right way.

The heater sits in the basement on a concrete slab, in the utility room, which is near the floor drain. The current water heater does not have a pan, but I'm planning on installing one, and routing the output drain from the pan to the floor drain (with an air gap). I'm planning on doing the same with the relief valve off of the water heater, keeping the two drain lines separated, and running both to the floor drain (keeping that all important air gap between the end of the drain pipes and the floor drain opening).

Anyway, I've been looking through the county's website (I live in unincorporated Jefferson County, Colorado) and have requested an account to get a permit. The county directs me to the universal plumbing code. I was able to obtain a copy of it, and started reading through it, and it seems extremely vague. I'm not sure what codes I need to observe for installation of a replacement water heater.

One thing that I will be testing for is the in-flow water pressure for the house from the city. If that is too high (over 80 PSI), I'll need to install a pressure regulator, which, as I understand in my county is another permit. If I need to put the pressure regulator in, I'll need to also add an expansion chamber to the cold-water side of the water heater, as the additional pressure from heat expansion can no longer be relieved to the city, as it's now a closed system.

The cold water inlet to the existing water heater already has a shut-off ball valve that only cuts the water to the heater, which is one thing I've been reading about.

So, this leads to a few questions.

  1. Where's a really good place to get a summary of the codes that I need to worry about (other than the universal plumbing code, which I can refer to for specific code details)?

  2. What pitfalls should I expect while doing this myself?

Finally, I noticed that a lot of the new Rheem heaters at Home Depot are WiFi enabled. This sounds really cool on the surface. Does anyone have experience and can comment on them? What about the fact that the water heater has a 110V powered igniter instead of a pilot light?

Best Answer

You should make two phone calls. The first to your local building department, which should be able to answer all your code related questions. They may even have a handout or other documentation, that outlines the requirements of replacing a water heater.

The second call should be to a local Rheem dealer, or directly to Rheem. They will be able to answer any questions you have about the equipment.

Some things to watch out for:

  • Make sure you drain the old tank completely, as water can be quite heavy.

  • When draining the tank, make sure you open the hot valves at fixtures. This will allow all the water to drain back to the tank.

  • When opening valves at fixtures, watch out for mixing valves. These can accidentally backflow cold water through the hot water pipes, which would lead to an undrainable tank.

  • If you have to install an expansion tank, make sure you charge it properly.

  • Make sure you know where to dispose of the old tank, as some municipal garbage collectors will not take water tanks.