How to Replace a Water Heater

So… our water heater has been on the downhill for about a year now. Now that the leak and corrosion became more substantial, we finally decided to get the stinking thing replaced. This tank was installed in 2001. We purchased our home in 2013, and in 2019, we are just now replacing it. 18 years is a pretty good lifetime for a water heater!

How do you replace a water heater? Shut off the water and gas, let the water cool, unhook the tank, drain it and hook everything back up, right? Well, there are a few more steps that I didn’t know about, so read on and follow each step accordingly:

A utility room with a furnace, water heater and water pump

This is what we were dealing with. The cold water in to the tank had corroded over:

An old water heater tank with the cold water in connection with corrosion

And when we removed the pilot light cover, you could see a lot more corrosion there too:

An old water heater tank with the pilot hole cover showing lots of corrosion

Ugh. I was overwhelmed and paralyzed with the pressure of replacing this old thing. I even told Sam, “Honey, you may have to carry us through this one.” Which didn’t seem to phase him at all.

We first looked online for a used water heater; which returned results for new ones at the price you’d pay at Lowe’s, or 10+ year old ones for super cheap.

After speaking to my parents, and venting my weight, I gained the advice from my dad “Erika, one thing you never want to buy used is a water heater. Trust me on this one.” And; they are helping us out with this water tank replacement.

With that decision made; we purchased a brand new water heater. Thanks for the advice and help dad and mom!

FYI: When we received a quote from a local plumber on a water heater purchase and installation, they wanted to up charge us for the appliance 30%, include a $355 installation fee, and a $35 service fee. No way! I’ll save myself a few days of selling my time, and do this whole operation myself. (Ok, with a tiny bit of Sam’s help. Hehehe) Time to put on my DIY pants. If nothing else, it will make for a great blog post!

These are the basic instructions on the water tank appliance box that we followed:

1. Check to make sure your unit is venting correctly by turning on your gas appliances (our stove top) and set a blown out match next to your vent on the top of your tank. If the smoke blows in, your vent is doing it’s job. First task done, and knowing our vent wasn’t blocked was a relief. (I didn’t know this was something I needed to be concerned about until I read an instruction to check the venting.)

2. Turn off the gas and remove the gas connection to your old water heater.

We had a valve shut off right on the inlet pipe, so we turned it to the off position, and removed the pipe that supplied the gas:

A gas inlet pipe hooked up to an old water tank in the process of being removed

3. Detach the venting:

Water heater tank with the venting removed

4. Turn on your nearest faucet and let the hot water run until it is cool.

5. Shut off the cold water supply and drain the tank.

We have a drain next to the tank so we didn’t need any buckets… but here is an ugly truth picture. Our tank was full of hard water deposits! We had to remove the water release valve, and get all the gunk out in order to drain it! Using a screw driver, we jammed that sucker in the hole and out came the hard water deposits.

Water heater tank with hard water deposit sludge coming out of the water release valve

It was pretty gross… but I have to say, I thoroughly enjoyed this step! It was quite the entertainment.

6. Remove the pressure release valve from your water unit:

Water heater tank with a pressure release valve being removed

7. Disconnect the water supply pipes to your tank, and remove the tank:

Water heater tank with the cold water inlet and hot water outlet being removed.

Disclaimer: we are not professionals, and this account is for entertainment purposes only:

Ok, so with the tank removed, we got down to the dirty business. And I’m talking about black mold, people! We found some hiding in our walls; so out came the old drywall, and the mold was removed using bleach. Don’t try to wipe the mold off. Get a spray bottle, load it up with a mixture of water and bleach, then get paper towels and put them under the mold, to catch the sludge when you spray. Work from the top down, replacing the towels as needed. We had masks and long sleeve shirts on.

After this cleanup, we spent 3 hours drying out this room by hand, with heat guns, and we left a space heater down there over night. We also treated our cleaned wall with hydrogen peroxide and white vinegar the next day. What I learned online was that bleach is effective in neutralizing the mold on non porous surfaces, but hydrogen peroxide and vinegar are more effective in neutralizing black mold in porous areas; like drywall.

A utility room with a furnace on the right, an open space to the left of it, and a water pump with a pressure tank on the left and open drywall in the background

Viola; no more mold. Now we are keeping drywall out of this area for now to keep an eye on the black mold.

8. Replace your old water heater with your new tank.

A new Rheem water heater tank in a utility room not hooked up to the water

9. Put the pressure release valve that you removed from your old tank back on the new tank.

A pressure release valve and copper tubing on a new water heater tank

For the gas and water hookups, we used a flexible hose kit to install our new tank, which included a gas hose as well.

A water tank installation kit with flexible hoses and a gas hose

10. Mark and cut the copper pipes to insert the new flex hosing, and use compression nuts to attach.

We also had to install new shut off valves, since our old copper pipes were now too long, and so we had to cut them out.

Sam first reconnected the water new flexible pipes and fittings back to the new tank using plumbers tape in all of the new joints. These joints ended up leaking, so he removed both hot and cold water connections and replaced the plumbers tape with Oatey Great White Pipe Joint Compound. This stuff saved our butts. No more leaks. We had to make a trip back to our home improvement store for this stuff. Only applying plumbers tape for the joints was not cutting it to tighten the fittings. This stuff helped us achieve a tight seal.

A brand new Rheem water heater tank with new flexible hosing attached to the cold water in and the hot water out

11. Make sure that the water release valve is closed on your new tank, and proceed to fill the tank with water. Watch for any drips that may occur with your new connections. If there are leaks, tighten your connection. (I know, easier said than done.)

12. After your tank is filled, reconnect the gas supply line.

13. Install the vent to the top of your new tank.

A vent hooked up to a new water heater tank

14. Turn on your gas supply line. Ensure there are no leaks with gas detection solution. (You can purchase an official bottle of this stuff for $9, but we used dish soap.)

A water heater tank with a new gas line installed and a bottle of soapy water next to it

15. Follow lighting instructions and set your thermostat.

Well, that was about $400 saved on installation, and another $100 saved on the unit itself. I’d say it was a job well done!

With Love, Erika Nora

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