BAC RV Club Forum

General Boards => Technical Support => Topic started by: Tom Pickett on May 08, 2026, 02:36:03 AM

Title: water pump issue
Post by: Tom Pickett on May 08, 2026, 02:36:03 AM
hi everyone
    i installed a new water pump had been damaged because the shop that winterized it did not get all the water out.
  The issue when the pump is on we are not getting full pressure getting air in the system.
  no leaks system works fine on city water. I believe there is a problem with a swain valve. I have not found and cracks in the pex tubing.
  What do you think
Thanks
Tom
Title: Re: water pump issue
Post by: Fred Brooks on May 08, 2026, 07:27:56 PM
   Hi Tom,
   Sometimes when a water pump is changed, there is air in the supply lines as well as in the pump itself. When the pump is turned on it cannot create water pressure because the pump is "cavitating". To eliminate the cavitation issue, loosen the water line on the "OUTPUT" side of the pump. Turn on the pump. You will hear it start to build pressure and leak water at the loose fitting. Tighten the output fitting and the pump will build pressure and then shut off. Hope this helps, Fred
Title: Re: water pump issue
Post by: Eric Maclean Co-Admin on May 10, 2026, 01:22:52 AM
Tom
If your unit has a winterizing valve set up to draw antifreeze into the system it's possible it was left in the winterizing position and the pump is simply just sucking air .

Eric
Title: Re: water pump issue
Post by: Tom Pickett on May 10, 2026, 03:37:17 PM
Hi everyone
   Eric yes my coach has a winterizing switch. The switch is in the normal position. pump is cavitating, anybody have this issue. Ifo believe it has something to do with swain valve but cannot find any info about it.
  Thankyou for all your help so far
   tom
Title: Re: water pump issue
Post by: Scott Shearer on May 10, 2026, 07:39:18 PM
Tom,

Assuming that your 2008 PT like our 2006 PT and has a gravity fill for the freshwater tank and a hose reel for city water. I don’t believe that there is a Swan Quick-Fill valve installed.

There is a check valve that prevents stored water from back feeding when the water pump is in use. I’ve included an image below. From my experience with our PT, when this check valve fails water will leak out of the hose reel connector.

If your coach has an auto-fill function via the Aladdin system, it is possible that the Red Hat electric valve is allowing air to enter the system.

 Another place to look, if your coach has the Prevent-a-Freeze winterization system, the changeover valve could be allowing air to enter the system. On our coach, the Prevent-a-Freeze changeover valve is mounted on the forward bulkhead above the Aqua-Hot.

-Scott
Title: Re: water pump issue
Post by: Tom Pickett on May 12, 2026, 01:48:10 AM
Scott
        that is what i am talking about . How is it activated
    thanks
     tom
Title: Re: water pump issue
Post by: Scott Shearer on May 12, 2026, 03:34:30 AM
Which of the listed devices are you asking about?
Title: Re: water pump issue
Post by: Tom Pickett on May 12, 2026, 02:34:37 PM
 The prevent a freeze, wiring schematic
i cannot find any info on this system,
thanks
tom
Title: Re: water pump issue
Post by: Scott Shearer on May 12, 2026, 06:03:28 PM
Tom,

I've not seen a wiring diagram for the Prevent-a-Freeze, the kit appers to be plug-n-play. You could give Swan a call in Bend @ 541.389.4668.

I believe the image below is what is installed in the our PT.

You can find the kit on Swan's Facebook page but it doesn't appear to be listed on their website. 

-Scott
Title: Re: water pump issue
Post by: Scott Shearer on May 12, 2026, 09:50:22 PM
Tom,

I missed this question, ‘How is it activated’.
 
In coach assist, the 2007 Patriot Thunder owner’s manual:
Page 152 shows the manual winterization valves.
Page 153 discusses how to use the optional Prevent-a-Freeze system.

2006 Patriot Thunder owner’s manual (which is searchable), page 195 shows the location of the Prevent-a-Freeze panel, the Service Center image in the 2007 manual does not show the Prevent-a-Freeze panel.

It doesn’t look like we have a 2008 PT manual online.

Scott