New pump, not building pressure

[DWR]

Fresh water tank full. All lines full of water. Unhooked City water connection. Valves in normal mode. Turn pump on. Opened all faucets one at a time. Pump works fine. Shut off faucet, pressure builds and pump shuts off. Travel to boondocking site., and the pump runs and doesn't build pressure and shut off. Not sure why. Checked connections. No leaks. Any thoughts?

[johnwen]

Try opening a faucet for a few seconds...usually you can hear a change of the pump sound as it primes.  Then close the faucet and see if the pressure builds.  You may have lost the prime as you traveled.

[DWR]

I have gone through all faucets and opened them and closed them. I can hear changes in the sound of the pump. Always keeping under the 2 minute recommendation for pump run time. Does not improve. Still stumped......  I have cycled through 4 minutes of cracking open faucets. Seems like a lot of air in lines. Perhaps I am leaving the faucets open to long. More than a few seconds....... Pump runs very quiet compared to when all is working properly........ 

[Steph and Dud B]

We've had this problem repeatedly in the exact scenario you describe. The "solution" was to open the hot and cold outside shower until the air purged from the system, which could take a couple of minutes. (Don't worry to much about the 2 minute limit. I once accidentally left the pump on for 20 minutes after draining the water from an old trailer and there was no harm done. 3 or 4 minutes is probably OK.) After that we'd be fine until the next stop when we'd have to do it again. 

Seemed like an air leak on the pump intake side, but I couldn't find one. I recently replaced the pump. One thing I noticed while doing that was that the pump filter didn't seem very tightly screwed onto the pump, something I had never thought to check, so look at that. Now the new pump is in. We'll see what happens next. 

Also, can you include your Oliver model and  model year in your signature line? Makes it easier to help people sometimes.

[jd1923]

1 hour ago, Steph and Dud B said:

Also, can you include your Oliver model and  model year in your signature line? Makes it easier to help people sometimes.

Yes, this is certainly a must! (at least your hull #)

After I fill the FWT, I put the hose on City Water and fill the 6-gallon Suburban HWH (we don't know if you have this or the Truma on-demand model). Then bleed the air out of the toilet first (if you have a standard model) then all faucets. Yes, good idea to also bleed the outdoor shower as it can be forgotten and you're right there when filling water! We have never run into the issue of air in the lines later (how does air appear out of nowhere?)!

OTT installs bare minimum water pumps! Fancy hulls, bottom-end pump that could use more PSI and GPM! Maybe we never have this issue due to installing a high-end US made variable-speed pump? This pump can run dry for days! Highly recommended. 😂

Edited July 12 by jd1923

[DWR]

I have gone through all faucets and opened them and closed them. I can hear changes in the sound of the pump. Always keeping under the 2 minute recommendation for pump run time. Does not improve. Still stumped......  I have cycled through 4 minutes of cracking open faucets. Seems like a lot of air in lines. Perhaps I am leaving the faucets open to long. More than a few seconds....... Pump runs very quiet compared to when all is working properly........ 

[DWR]

Oliver haul #1619, 2025.Legacy Elite 2. Thank you.... I will did follow the de winterization procedure. Thinking going back to a known starting point would be prudent. I will continue and let every one know how it works out.... Again thank you so much for your responses. I absolutely love this travel trailer. But I do have a learning curve to work through. Worked all day, and am "home" for the night. I did have a concern about the trauma water heater with so much air in the lines...... Did not want to harm that in any way. Any thoughts on that? Again thank you all .......

[Tom and Doreen]

You can try setting your valves to the normal position, turn your pump on, then turn the valve circled in the picture below  'on' briefly. You will hear water rushing into your fresh tank. What this does is pump water from your fresh tank back into your fresh tank. This will purge the air out of the pump and associated components.  This has happened to me many times after traveling and arriving at a site, somehow air gets into the system. 

Edited July 13 by Tom and Doreen

[DWR]

thank you.... will give it a try........

[DWR]

I see there is no teflon tape where the screen attaches to pump. Made me raise an eyebrow. That connection might not be the best without it..... Just thinking out loud..... Thanks again.....

[Steph and Dud B]

Now that you mention it, ours doesn't have Teflon tape there, either. Anyone have Teflon tape at the connection between the pump and its filter? 

[Tom and Doreen]

I believe that the filter / screen utilizes an 'O' ring for a seal and it's on the low pressure / suction side of the pump.  

[johnwen]

Yes... only an o-ring on ours as well...no Teflon tape.

[DWR]

Just to follow up on post. What I found ...... No oring, where screen housing connects to pump. Flexible line attached to screen housing did seem a little loose, snugged it up. One of the "quest fittings (unsure if that is the brand) was loose enough to allow air to draw in ....... After correcting these issues, all works great. Small issues easily remedied..... Thanks for the conversations. All tips used and helpful......

[DavePhelps]

Glad you discovered the problem.

Regarding the water filter o-ring, I like to lube it with a small amount of silicone based plumber's grease. It helps with the seal and keeps the o-ring in good shape. Also, don't over tighten the filter screen housing. Firm hand tight is all that is needed. No tools!
Cheers,

Dave

[DWR]

O Ring size: 9/16 x 3/4 x 3/32 seems to work fine....... Just thought I would throw that out there in case any one runs into the same issue......

[John Dorrer]

On 7/12/2025 at 1:39 AM, DWR said:

I have gone through all faucets and opened them and closed them. I can hear changes in the sound of the pump. Always keeping under the 2 minute recommendation for pump run time. Does not improve. Still stumped......  I have cycled through 4 minutes of cracking open faucets. Seems like a lot of air in lines. Perhaps I am leaving the faucets open to long. More than a few seconds....... Pump runs very quiet compared to when all is working properly........ 

Is you outdoor shower knobs closed tight? Open outdoor faucets have caused similar issues.

 

Update: I was replying to the original post and didn't see the complete thread🙃

Edited 1 hour ago by John Dorrer
Updated Comment