Amtrol ST-12-C THERM-X-TROL ASME Expansion Tank, 5 Gallon  Logo
Posted on Mar 28, 2010
Answered by a Fixya Expert

Trustworthy Expert Solutions

At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.

View Our Top Experts

Lots of water on basement floor at pressure tank.

When we flush the toilet the pressure drops to 38psi, pump turns on, pressure rises to 90 psi, pressure valve blows off air and water, pressure drops back to 50 psi. We also have surges in pressure when taking a shower.

1 Answer

jimmy

Level 3:

An expert who has achieved level 3 by getting 1000 points

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Vice President:

An expert whose answer got voted for 100 times.

  • Master 409 Answers
  • Posted on Mar 29, 2010
jimmy
Master
Level 3:

An expert who has achieved level 3 by getting 1000 points

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Vice President:

An expert whose answer got voted for 100 times.

Joined: Mar 09, 2010
Answers
409
Questions
1
Helped
146577
Points
1094

Sounds like the bladder tank at the well is ruptured this will cause pressure surge, and pump short cycling, and needs to be replaced asap.

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Water level in gas water heater ?

redux 1
all that is 100% normal, (new T&P not leaking now.
a real tech would make sure the thermostat on the side of tank works right.
after all the P&T is to protect it from go to steam 212f} and exploding
the tank is full of hot water, this is NO DEMAND hot water heater, it this old design is full of hot water all the time
and both the thermostat senses it and the P&T guards it from overheating not exploding

if that is confusing call a real plumber to the home and have it check it out and even explain how all this works.
some will for free, called GOOD WILL.

call them stop guessing.
do not tamper with T&P and for sure never try to make it stop leaking or making noise, DOING CRAZY acts.
replacing it is all good.

be safe don't guess, OK?,
0helpful
1answer

I have a ideal mini c28 which is loosing pressure when the boiler is off, but when topped up and heating turned back on the pressure keeps rising

According to the laws of physics, pressure will rise as temperature increases and falls as temperature decreases in a closed system. The issue is how much does the pressure change for a given temperature change. The more air in the system, the less the pressure change, and vice versa. Vent your registers (pump must be off). If they are noisy from water flow, vent again. Let the boiler come up to temperature and shut itself off. Check the pressure at this point. If it is less than about 15 psi, add water to get it to 15 psi. If it is over 15psi, vent the surge tank to get to 15 psi. If your surge tank is totally full of water, you will have to find a way of getting air into it. Always check your pressure at the same water temperature to really know if you are losing water from the system.
0helpful
1answer

My boiler has a squeeling sound during the warmu up. I think it is coming from the expansion tank?

The squealing sound generally comes from a circulator pump, if it has a drive coupling between motor and impeller housing there is an oil cup/or oil hole, add oil until it is full! If it is a cartridge style circulator you may have to replace it.

Sometimes air in a system will cause this squeal noise as well. Purging the air out of system may be required. If you need to know how to purge a system there is a good pdf file at this link for $8.95 The Basics of Purging Air
From your Forced Hot Water System
&
Troubleshooting A Leaking Boiler
Relief Valve
Miller Furnace Books Repair

The Expansion tank is factory set to 12 psi and the only way to tell if it remains with 12 psi is to drop the system pressure to zero and check the tank with a pressure gauge. If water comes out the air valvestem when you apply the pressure gauge, the tank is bad, replace it! If there is less then 12 psi on the tank add air to 12 psi and open water valves back up to normal operating pressure. Usually the feed valve will automatically stop at the preset setting.If the boiler is leaking water out any relieve valve drains, the feed valve, relief valve and or expansion tank may need to be replaced.
0helpful
1answer

How to top up the pressure on the boiler

According to the laws of physics, pressure will rise as temperature increases and falls as temperature decreases in a closed system. The issue is how much does the pressure change for a given temperature change. The more air in the system, the less the pressure change, and vice versa. Vent your registers (pump must be off). If they are noisy from water flow, vent again. Let the boiler come up to temperature and shut itself off. Check the pressure at this point. If it is less than about 15 psi, add water to get it to 15 psi. If it is over 15psi, vent the surge tank to get to 15 psi. If your surge tank is totally full of water, you will have to find a way of getting air into it. Always check your pressure at the same water temperature to really know if you are losing water from the system.
1helpful
1answer

Leaking hot water heater

If it is older than 15 - 20 years and leaking on the floor under the tank, purchase and install a new appliance, If the T&P valve is leaking, change the valve. If it still leaks, replace the expansion tank which should on the supply water line. Try not to install an expansion tank "on its side". BEFORE YOU DO ANYTHING, make certain your incoming water pressure does not exceed 65 -70 psi. This could be the real problem. If so, install a new water pressure regulator. It is usually located inside the basement wall. In a Garden Home, it may be outside at the curb in the ground by the water meter. It may be in the ground buried near the entry through the foundation. It may be near the water heater.
0helpful
1answer

Hello,

The pressure tank psi may be too high. To set it you get the system to pressure up and stop then check that water pressure. Whatever that is, is what the tank should be set at. Too much air pressure and the water pressure will suddenly drop before the pump kicks in.
To set the tank properly turn off the pump, drain all water pressure, then set the air pressure in the tank to the same as the water pressure was. Turn it back on and check again.
0helpful
1answer

Too much water draining from Vulcan Electric H/W relief valve.

Dear Julie. Do you have an expansion tank installed? If so it is probably waterlogged. If you come home shower etc. use lots hot water then go to bed or leave the cold water in your tank heats and expands as it heats. In the old days a toilet ballcock valve would relieve this pressure but modern toilets with diaphragm valves wont so the pt valve relieves pressure. Installing an expansion tank on the cold water line near the heater will absorb the extra water & stop the pt valve from activating.
0helpful
1answer

When hot water is on & toilet flushed the temp drops

Check strainers and screens into the sink, at the spout and into the hot water heater. Sediment buildup could be limiting the flow which woul make the system more susceptible to pressure drop when the toilet is flushed.
0helpful
1answer

Pipes humming in house

From your description, I am guessing you are on a deep well with this answer. I think you have an issue with the well pump. To isolate it do this...........

Turn the main supply valve off to the house. Your well tank should have a hose bib on the well tee. Hook a hose up to that and run it outside. Open the valve to the hose until you heard the pressure click on which activates the pump. After the click close the valve and listen for the hum. If it still hums it is the Well and not the piping in your home.

Will follow-up.............

Please rate this response after testing and Good Luck, Phil
Not finding what you are looking for?

246 views

Ask a Question

Usually answered in minutes!

Top Amtrol Water Heaters Experts

Brad Brown

Level 3 Expert

19187 Answers

Paul Carew

Level 3 Expert

3808 Answers

ADMIN Andrew
ADMIN Andrew

Level 3 Expert

66963 Answers

Are you an Amtrol Water Heater Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...