Plumbing in the Home/expansion tank


Mr. Ambler -
About 18 months ago I installed a new 40 gallon electric water heater. I immediately had pressure increases on my plumbing. I installed a small (1 gallon?) Watts expansion tank - which isn't very close to the heater. It is maybe 10 - 12 feet away from the tank. It worked well for about a year. But now it isn't working. The pressure coming from the faucets is VERY strong for about 20 seconds and then returns to normal. I went down there and measured the pressure on it, and it was about 35 PSI. The label says 20 psi pre charged and 80 psi max. The pressure relief valve on the heater itself doesn't not appear to be getting triggered. The temperature setting on the water heater itself is quite low. I can hold my hand in the stream of hot water without discomfort. The pressure regulator from the street water source was replaced a few years ago, and I believe it is fine. No problem there. I upper the pressure in the expansion tank to 70, but i think that may have been a mistake.  Any ideas?  Thank you very much sir.

Dear Bill,

   The expansion tank is the correct solution to the problem.  See when cold water is heated it increases in pressure and without sufficient room for the expansion it will come out of the faucet with suprising force.

   The expansion tank needs to be checked.... this is done by removing the tank from the system and then checking the pressure in the bladder.  You may need 40 to 60 lbs of air to offset the expansion of your water, but once it is properly set it should work well for quite some time.

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Thomas Ambler


I am experienced at troubleshooting and solving all types of plumbing problems. Issues related to specific manufacturers fixtures and specifications though are beyond my field of expertise. I have dealt with problems in both rural and urban areas, and with water supply and drainage systems. Plumbing issues can be very obscure... such as odors, stains or occasional seepage. I have even had to chase rats from a customer's sewer line.


I have 25 years experience dealing with plumbing systems (which also includes hot water and steam heating systems). My main expertise is in diagnosing and solving problems. I have worked in construction and installation of new systems but do not regard myself as an expert in that area.

Asbury Park Press, Seattle Times, Denver Post.

I completed high school and one year of college. I served 4 years in the Marine Corps and have education in electronic and electrical troubleshooting and repair. I have attended classes on installing and repair of oil burners, and I have EPA universal certification for air conditioning and refrigeration. I am now enrolled as a full-time student at Everest college to re-train for a new career. Any donations of financial support would be greatly appreciated.

Past/Present Clients
All of Denny's Restaurants in NJ, Several Burger King stores, I have done work at two different homes for Bruce Springsteen. I have also worked for Jim Johnson (of J&J) and his family, Whitney Houston, Steve Forbes and many others.

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