City water on, fresh water pump on

[Rroobb]

Everything is getting water from the city side one at a time or individually.
Step on the flush pedal and the pump kicks on ,nothing else causes the pump
To come on accept the toilet.
I have turned off the pump I get good water everywhere including the toilet.
Pressure valve only affected by the toilet?

 

[16ACE27]

There's no reason to have the water pump on when connected to City Water.
Depending on how your plumbing is configured, the opening of the toilet valve may cause a momentary pressure drop in the pump's pressure switch to cause it to cycle, regardless of the presence of city water.

 

[ducksface]

Unless a criminally long shower is going to happen there is no reason to be connected to shore water.

Shore water can cause many more problems than just the slight one you're experiencing.

 

[Rroobb]

I agree no need to have the pump on when on city water, I agree with the momentary pressure drop
But that should happen when I turn on the sink or show or both at the same time, this is only happen when I step on the flush valve

 

[16ACE27]

I agree no need to have the pump on when on city water, I agree with the momentary pressure drop
But that should happen when I turn on the sink or show or both at the same time, this is only happen when I step on the flush valve

The toilet has a ball valve which starts the flow with a dump.

The other valves are globe valves and start the flow with a trickle.

 

[Rroobb]

Not sure why that would effect the city water verses the fresh water
City water has more pressure so why is it allowing the pump to kick on

 

[16ACE27]

Not sure why that would effect the city water verses the fresh water

That's why you asked the question and I assume you meant city water vs pump water. They're both (or should be) fresh water.
And I assume the pump comes on whether you are on City water or the pump when you flush the toilet? So not sure what the "verses (sic)" is about.

It's all about dynamic fluid flow.
You wouldn't have the issue if you had a properly installed accumulator.

Turn off the pump if using City Water and don't lose any sleep over it.

 

[Rroobb]

Your absolutely right,
No need to lose sleep
I'll try

 

[Tom3]

Not sure why that would effect the city water verses the fresh water
City water has more pressure so why is it allowing the pump to kick on

Thor Class A & C Owners Manual (2022) repeats this statement a number of times, “Do not turn ON the water pump when using water from an external source. Only run the water pump if using potable water stored in your fresh water tank.”

So I have to ask why you need to solve what appears not to be an issue?

 

[Rroobb]

I guess my curiositcuriosity

 

[ducksface]

I would eliminate seven worries by eliminating shore water:
Vandal
Burst
Pressure surge
Pressure drop
Freeze
Theft
Leaving your pump on while using shore water.


Everyone here knows at least one story of any of the above.
Using your pump eliminates all seven.

 

[Rroobb]

Thanks for all your help and advice
You right use one source at a time and don't lose any sleep
Good new, looks like everything on the RV has survive the winter, first trip will be April 1st