The little tank that leaked

We were having leakage problem with our potable water expansion tank in the past few weeks. We noticed it when the basement was cleaned up and then there was this wet spot on the floor. It turned out that rust-colored water was dripping from the ridge in the middle of the tank. It was a slow leak so I was never in a hurry to deal with it -- especially when I am not as handy as CherkyB.

So... the other day (last Thursday) I asked wife to call plumbers to find out how much it would cost to get a new tank installed. The next thing I know, I got a phone call from her in the middle of the day asking me what pressure range to buy for the tank. The conservation went something like this:

Wife: "What is the size of the tank we have?"
Me: "Huh? What tank?"
Wife: "Water expansion tank. The one that is leaking."
Me: "Oh. I don't remember. Can I get back to you later in the day?"
Wife: "I am at Home Depot already."
Me: "I thought you were supposed to call plumbers for installation pricing?"
Wife: "Yeah, but I am at Home Depot already so I will just buy one and we can return it if it doesn't work"
Me: "Okay... you need to make sure you get a tank with max pressure of 150"
Wife: "I see two tanks here and they are blah blah blah mdoel #s.... not sure about pressure"
Me: "Maybe I can go buy it later after work?"
Wife: "Nah, it's okay. I will just get one that looks like the size of ours."
Me: "I don't know. We are supposed to match the pressure."
Wife: "You can always return it. I will just get it."
Me: "ok..."

Half an hour later I got another phone call:
Wife: "I just opened the box. The pressure is between 40-150"
Me: "Okay. I don't know how to install it though."
Wife: "Why don't you ask your co-workers?"
Me: "I will double check. EDF said to drain the pipe, unscrew the old one and screw in the new one"
Wife: "Ok"

Later I got home to find a new water expansion tank with 2x the capacity of the old one. Hmm... this does not look like the same size as the old one...

I then read the installation warnings and how we are supposed to match the pressure of the tank to the pressure of the pipe... along with several warnings about how it should really be installed by professionals who know what they are doing to follow local code. That is when I went back upstairs to tell wife that we may still need to call plumbers to install the tank.

This morning wife asked whether she should call plumbers and I said to give me a day to find out whether someone had installed this at work. Well, I did not find anyone who had actually installed one. Some asked why I have a potable water expansion tank and all I could say was that it was for the water heater and it was there when we bought the house.

I went by EDF's cube for further consulation. He was sitting in his cube but he had a "DO NOT DISTURB" sign posted with notes saying "you are NOT an exception. Come back at the following times..." Figuring that note was not for me, I popped my head over the wall and asked whether I really need to pressurize the new tank or whether I should come back in half an hour. He created an exception and answered my questions... At the end of the day I ran into him in the parking lot and found out that everyone figured they were exceptions. Hmm... I guess that was not too surprising.

After dinner tonight, I went downstairs to look at the leaky tank some more. It had two drips of water on it. I asked my brother-in-law what he thought and he said the installation seems to indicate the need to match pressure but he also could not find the pressure meter. Since no one has yet to say "Don't do this! It is highly dangerous", I figured I'll give it a shot after everyone has used the water and was made aware that we might be out of water for a while.

The first step was to turn off the water heater since installation guide said to turn everything off. We then turned off the main pipe and then drained the pipe using the tube and drain mechanism in my first DIY project. It took about 5-10 minutes to drain the water and during that time we realized that we probably did not need to turn off the water heater since we had turned off this valve to prevent water from going in/out of the water heater.

The next step was to unscrew the old tank. When I climbed on the ladder, I noticed that the old tank had no supporting mechanism to allow one to apply a wrench to screw it on/off. Wife said "Just use your hands and twist the tank". I twisted the tank and it came off easily.

Then came the easiest part - screwing the new tank. This new tank had a supporting mechanism to allow a wrench to be applied so it was relatively trivial to screw it on tightly.

We turned the water back on and nothing exploded... so that was a good sign.

Then we read the instructions on how to turn on the water heater and found out that we needed to light it manually. It took some time but we eventually got it to work. It reminded me of the early days in my childhood when I used to be so scared of lighting the gas-powered water heater. The fire went out often in those days and I always thought it was going to explode when I lit the matches -- not to mention the tank was out in the dark backyard. I will probably check the water heater tank often in the next few days out of paranoia.

We do have a CO detector in the house so hopefully it will detect gas. Though I have never seen it register an alarm after installing it -- it is either working really well or it is not working at all.

The important lessons learned are:
1) wife is always right. she bought the right tank (it fits).
2) wife is always right. she told me to unscrew the old tank by hand and she was right.

I am such a lucky man... hopefully the new tank will hold when the sprinkler turns on...