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Why does pressure in captive air tank keep getting higher?

I checked and set the pressure in my captive air tank by the proper procedure to 40 pounds( shut off pump, drain system of all pressure , check tank pressure, set to 2 pounds below cut-in pressure of pump). After a short ime noticed that my water pressure would drop to almost nothing before the pump kicked on; a classic symptom of the pressure in the captive air tank being too high. When I checked the pressure in the tank again, by the same method (pressure drained from system) it read 55 pounds. I thought I screwed up so I readjusted the pressure to 40 pounds. The next day the same thing occurred. I checked the pressure in the tank (again, after draining the system) and the pressure was back above 50 pounds. Yesterday I set the pressure at 10 pounds. The water pressure in the house seems good now. I checked the pressure in the tank (again after draining the system pressure) and it's now at 13 pounds. Can someone please explain how the air bag is gaining pressure???

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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: I have a whirlpool front load washing machine model WFW8300SW00

Hay Crab.
what I have found is that the washer thinks it is not pumping out .. if your drain pump is clearly removing the all the water in a good time... then the problem is your pressure is telling the computer that it still has water in the machine...

replace the pressure switch and it will solve your f21 error.

It is a round unit on the right hand side on top...with a tube and wires going to it...let me know if it helps

Posted on Apr 05, 2008

  • 1 Answer

SOURCE: whirlpool duet sport wfw8300sw00 f-21 error

Unplug the machine. Unscrew the 3 screws under the front edge of the washer. The service technician manual is attached to the panel that slides down and off. Find F21 code. See suggested procedures. Note: My drain pump filter had a baby wash cloth in it along with some change that was disrupting the flow. It is exceptionally easy to remove, clean, and reinstall. Just line up installation notches when reinstalling. Whirlpool should have mentioned this filter in the User & Care Guide, but I could not find it anywhere in there.

Posted on Mar 20, 2009

  • 59 Answers

SOURCE: Drain valve in Porter Cable air compressor

this valve works backwards, you screw it out to stop airflow. If that doesn't work, replace the valve.

Posted on May 25, 2009

  • 69 Answers


Most likely the pump is leaking somewhere, if the new hose is not leaking. Hoses don't just burst without showing signs or wear and tear, i.e. cracking and splitting. The pump was probably having problems, and this caused the hose to burst. Look for signs of leakage, and if you can't find them, the pump is shot.

Posted on May 27, 2009

  • 256 Answers

SOURCE: Drain valve on air compressor won't open or close

I would use an ajustable wrenck to try and open the valve. Being at the bottom and in the water, this is a common occurrence. to replace the valve, there is a Hex nut outer fitting (part of the valve) that you have to remove right by the valve "T" handle. Put a wrench on this and remove the complete valve. It too will be very hard to remove. When you install the new valve, use some anti-seize compound to make future removal easier.

Posted on May 31, 2009

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