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Topic: Water Pump and Accumulator (Read 887 times) previous topic - next topic

Water Pump and Accumulator

Awhile back I replaced the water pump in our rig. We now have an Aqua Jet II (55-Aqua Jet-ARV). I chose to leave the accumulator in the system in that it was working just fine. Still is. It's a Flojet model 20799. The tank indicates that the proper pressure is 3 psi < the pump's "switch on" pressure. Anyhow, I wrote Aquatec to find out what my pump's switch on pressure is. Here's their response for those of you that might have the same question or are trying to decide whether to retain your accumulator.

Quote
We do not recommend that you use an accumulator tank with our pump. The tank may cause a non-shut off condition of the pump. We recommend that you remove the tank. Our on pressure setting of the pump is 42 psi.

I guess I'll remove ours one of these days, probably when the pump won't shut off!
jor
93 225
95 300
97 270
99 320

Re: Water Pump and Accumulator

Reply #1 –
Hmmm... there ought to be a fix for this that would keep the accumulator in the system. I really like having that accumulator because at night you can flush the toilet without having the pump come on and wake someone up.

Perhaps a relief valve?

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Water Pump and Accumulator

Reply #2 –
??? A properly installed functional accumulator doesn't keep the pressure from reaching the "turn off" point. I don't understand the recommendation.

The accumulator is generally set to a pressure near the "turn on" point. Is the 42 psi the "turn on" or "turn off" point? I did not find the values in the manual for the Aquajet.

Our old pump was set to turn on at about 25 psi. I set the accumulator pressure to that value with the water system open. All worked well and as expected. When I installed the Aquajet ES, I left everything set the same and have been pleased with the results.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Water Pump and Accumulator

Reply #3 –
I just installed an ShurFlo 4008 since my old accumulator became waterlogged. Yes I installed it without Steve Cooke or Dave Abel's help. They weren't here and I couldn't find anyone else to Tom Sawyer into doing it.

I thought I would save some money by eliminating the accumulator tank but now that I have the 4008 installed, I prefer a system with the tank so I bought a new accumulator yesterday. According to the pump data sheet, the new pump comes on at 40 psi and shuts off at 62 psi. According to the new accumulator tank, the pressure of the tank must be at least 2 pounds lower than the turn on point, 40 psi in our case, so the tank pressure should be less than 38 psi.

The only problem I have completing the re-installation of the new tank is that I put one of the slip on, O ring type plugs on the end of the gray tubing and I can't get it off. I guess it is like the Shark Bite type fittings but it was designed for the old gray pipe. How do you get that type of fitting off? I really don't want to have to cut and replumb the tank.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Water Pump and Accumulator

Reply #4 –
Kent, If it is a Sharkbite they make a tool to remove it.  It looks like a little horseshoe, it depresses the collar and then it will come off the pipe. If a Watts type you screw the collar back and depress the ring and it will come off.
Gary B

Re: Water Pump and Accumulator

Reply #5 –
Gary, thanks a lot. Can I get the tool from Home Depot?
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Water Pump and Accumulator

Reply #6 –
Quote
The accumulator is generally set to a pressure near the "turn on" point. Is the 42 psi the "turn on" or "turn off" point? I did not find the values in the manual for the Aquajet.
JD, it's the turn on pressure. I wrote them because they did not include it in the documentation. Yesterday I set my accumulator  pressure to about 39 or so according to the label on the accumulator (3 psi less than turn on). Before I did that it had been about 50 psi and everything seemed to operate normally. I'm going to leave the accumulator in until it fails.
jor
93 225
95 300
97 270
99 320

Re: Water Pump and Accumulator

Reply #8 –
Howdy Huck (Kent),

Really? You worked on your water system?  LOL !!!  I'm glad it went well..

I'm sure Dick S is like me and wants to know what caulking you used?? 

Hope all is well, TTYL,  Dave A
Dave and Nancy Abel
'00 U320 36' WTFE  Build #5669
'10 Jeep Wrangler Unlimited Rubicon
Livingston, TX  SKP's Fulltiming

Re: Water Pump and Accumulator

Reply #9 –
Thanks to all for updates on "turn on"/"turn off" pressures. I plan to measure the pressures on our new pump with a gauge and set the accumulator appropriately for our system. It's working now. If things go well, I won't "fix it until it doesn't work right any more." :D
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Water Pump and Accumulator

Reply #10 –
I have an Aquajet ES which was recently installed. The advertising at RV Water Filter Store: Standard Filter Canisters for Whole RV claims 3.5 gpm at 65 psi. I just measured pressures at the "air pressure fill" end of the accumulator. I used a Longacre Racing brand dial gauge with a range of 0-60 psi. I measured a "turn on" pressure of 32 psi. I found the "turn off" pressure to be 58 psi. It set the base pressure of the accumulator to 32 psi. Current ambient temperature is about 94F. The base pressure of the accumulator will drop a bit at lower ambient temperatures.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX