Expansion tank replacement
 

Several neighbors as well as myself have had the expansion tank bladders fail, we have all replaced these ourselves, here is basically what is involved.

Lowe's sells 2 of these, one is rated for 1 year warranty and one for 6 year warranty. The 6 year warrant one exactly matches what was installed originally.

1. Turn of power to hot water heater.
2. Turn off water supply to hot water heater.
3. connect a hose to the drain valve of the hot water heater and open the valve to reduce pressure.
4. Using two (2) wrenches remove the existing expansion tank. Keep a towel handy as you will have some leakage.
5. Take a water pressure gauge and measure the pressure at a hose bib.
6. Pre-charge the new expansion tank to that pressure with an air compressor.
7. Apply two layers of Teflon tape to the threads of the new expansion tank.
8. Screw the new tank in place and hand tighten.
9. Using two (2) wrenches tighten the new expansion tank.
10. Turn on the water supply and check for leaks.
11. If you have a small leak try tightening the expansion tank, be sure to use two wrenches against each other.
12. Turn the power back on to the hot water heater.

Hope this helps.

Perfect......

How did all of you know that the expansion tank bladder failed? Is there a way to test? Are there symptoms that can be observed?

At first I thought step 5 would put a stop to me doing this DIY project -- "Take a water pressure gauge and measure the pressure at a hose bib." Then I remembered that I have water pressure gauges on my NOVA filter system. Bingo!

Right on V.T....! I just replaced mine the other day. Typically these will last 6-10 years. It is an easy DIY job.

To tell if you need to replace this you can gently tap on the side of it. You should hear a difference in sound as you go up.....there is a rubber bladder inside and kept a "pillow" of air to compensate for varying pressures within your domestic water system. Thus the difference in sound.

If you hear no sound difference, or if water comes out the Schrader valve when checking it, your tank bladder has compromised and the tank should be replaced.

On a side note, if you have not replaced this expansion tank in years and you find yourself paying a plumber to replace an old water tank, you might as well have them do both when you have them there.

Frank D.

One symptom may be water leaking out of the relief valve.

Question: Can you skip Step 3 by opening the hot water faucet in the laundry tub next to the water heater? That would eliminate the risk of causing a leak in the drain valve.

If the relief valve is leaking (not tripping), the valve needs to be replaced. It wouldn't necessarily indicate a defective expansion tank.

I guess so, but the drain valve was right there and you are really supposed to drain some water once a year or so, so that is what I used.

OK, I'll be the ignorant person today...
Having not yet moved into a TV home, where would one find such expansion tank and what is its purpose?
... (Come to think of it, can I have an expansion bladder installed in myself?)

Google is your friend

If you have the “Push/Pull” plastic water shut offs under your sinks and by your toilets, and occasionally you find one or more turned off and you push it back in to get the water flowing again, it is because of the tank on top of the water heater. Time to replace it, and if your water heater is more than 15 years old, you may want to replace that before you HAVE to replace it.

Over 40 years I have owned 4 houses previous to moving to TV. None of the hot water systems had an expansion tank installed. I never noticed any variations in water pressure or premature failure of the components. I would think if there was excess pressure build up sufficient to cause damage it would pop the pressure relief valve on the hot water heater. A Google search didn't convince me as to the need of an expansion tank.

I think a big reason so many tanks fail here in the villages is from improper installation. When these tanks are installed the expansion tank pressure is supposed to be set to match or be just below the house pressure. When these tanks are new they are pre set to approximately 40 psi off the shelf. Most homes here average about 60-70 psi or higher. I believe this will shorten the life of the bladder if not set properly prior to installation. We have seen tanks fail anywhere between 3-5 old and they should last 7 years. If I had a tank that was 5 years old and it tested good it would definitely be on my list to change for preventative maintenance.
Also if you have no filter and straight chlorine hitting the rubber bladder that will shorten the life also. The chlorine level in the villages is at 1.5 and this is almost 6 x higher than up north.
Spread the word help your friends and neighbors out hardly anyone knows they have a expansion tank let alone how to test them annually.

Btw it’s Florida code to have one for the last 20 years ( I believe)

Here are some reasons:
1. The expansion tank is required by code
2. A normal water pressure is about 60 psi, and the expansion tank is designed to maintain that pressure level.
3. The relief valve is a safety device that will only trip if the pressure exceeds 150 psi, which is way higher than a normal pressure. These valves often get clogged with calcium deposits and may not function properly over time.
4. Older houses are less likely to experience excessive water pressure because they may have small leaks in the system or may not have a good backflow preventer.
5. If you use all the hot water in the tank, and then shut off every fixture in the house, the tank will be full of cold water which will heat up. As it heats, the water pressure will increase due to expansion which can result in a dangerous pressure level. The expansion tank is designed to allow for the water to expand and keep the pressure down.

Thanks for the information, so if replacing an expansion tank, should the tank be charged to 60 psi or 40 psi? I don't see an easy way to determine the system pressure to be able to match it in the expansion tank.