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Topic: Plumbing Mystery  (Read 434 times) previous topic - next topic

Plumbing Mystery

This one has me stumped. When shower is running and temperature is stable. If you operate the toilet the shower gets colder. I don't get how asking for cold water at the toilet would make the shower get colder. I tried the bathroom sink and it had no effect on the shower. Just the toilet. Thoughts on this.
Robert scratching head.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Plumbing Mystery

Reply #1 –
When cold water flows I reduces the pressure in the hot water lines.
Check air the pressure in the water system pressure, it should be about 40 lbs.
If water squirts out of the pressure tanks air valve you need a new tank.
Tim Dianics
Pam Sapienza
Vader PupZilla Labrador Canine Beast (AKA Pup)
Columbia, MO
1996 U320 4000
2021 Jeep Gladiator, Diesel

Re: Plumbing Mystery

Reply #2 –
I have heard of people plumbing the toilet to hot water in a residential home to prevent tank sweating.  I realize there's no tank in an RV toilet but maybe it was done for the bowl or maybe just a mistake at the factory?  You might check.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Plumbing Mystery

Reply #3 –
Quote from: JohnFitz –
I have heard of people plumbing the toilet to hot water in a residential home to prevent tank sweating.  I realize there's no tank in an RV toilet but maybe it was done for the bowl or maybe just a mistake at the factory?  You might check.

I don't think that's the problem. The water system on this coach is zoned thru a distribution manifold. There is only one water line to the toilet and it's cold water.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Plumbing Mystery

Reply #4 –
Quote from: TGordon –
When cold water flows I reduces the pressure in the hot water lines.
Check air the pressure in the water system pressure, it should be about 40 lbs.
If water squirts out of the pressure tanks air valve you need a new tank.

But that doesn't explain why only the toilet makes the shower get colder but the bathroom sink doesn't.
2008 Nimbus 342
Build# 6464
ISM 500
Allison 4000 w/retarder
2021 Jeep Grand Cherokee

Re: Plumbing Mystery

Reply #5 –
Quote from: Res777 –
But that doesn't explain why only the toilet makes the shower get colder but the bathroom sink doesn't.

Other than using more water when you flush vs. sink?  I do know that when I was about to take a shower, I always told wife not to do dishes, etc.  Water remained within tolerable temps.  Same with a residential home!  No secrets!
Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus
 

Re: Plumbing Mystery

Reply #6 –
1/2" incoming pipe is only rated for two fixtures .
You problem is generally a pressure issue, try hooking to city water and if the problem disappears then you know it's a pump/ pressure issue
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

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