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Topic: Pressure/, accumulator tank (Read 323 times) previous topic - next topic

Pressure/, accumulator tank

Removed mine today to drain. I noticed it weighed a lot. Sure enough I depress the air fill valve and water came out, so the diaphragm has a hole in it. Probably 40 to 50 bucks at the RV place or more. You can buy the exact same thing called a different name at Home Depot. Just ask for a water heater thermal expansion tank only about 30 bucks and most likely in stock. Last I heard there is only one company in the US that makes these, and that company is amtrol.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Pressure/, accumulator tank

Reply #1 –
A lot of us just do away with the accumulator. That's what I've done in the past and will do with this rig. Gives you a little more room down there too.
jor
93 225
95 300
97 270
99 320

Re: Pressure/, accumulator tank

Reply #2 –
Quote from: jor –
A lot of us just do away with the accumulator. That's what I've done in the past and will do with this rig. Gives you a little more room down there too.
jor
It's function is to protect the pump motor from burnout from short cycling. Some of the newer more expensive variable speed pumps don't need it.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake
 

Re: Pressure/, accumulator tank

Reply #3 –
Need for an accumulator depends on the water pump.

The old-style (and more reliable) ones benefit from an accumulator.

The newer-style variable speed pumps do not need one.

To test an accumulator:
Remove the blue plastic cover over the fitting on the end of the tank.  You will find a "regular tire type" valve.  Press it for just an instant (small screw driver, key etc). If water comes out, it is BAD (diaphragm busted). Replace it.

Correct PSI is 2 PSI less than "cut-in" PSI for the pump.  So for most, that means 23 PSI.  So with shore water off, pump off, pressure bled off ( open faucet) set to 23 PSI.  A bicycle pump works just fine if you don't have a compressor.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020