water pump psi

[RPC]

I have a 2014 thor chateau 23u. I need to change the water pump. It has a 40 psi pump in it now. Can I put a 55 psi pump in? Thank You

[cavie]

Originally Posted by RPC

I have a 2014 thor chateau 23u. I need to change the water pump. It has a 40 psi pump in it now. Can I put a 55 psi pump in? Thank You

You can but why? 40 # is more then enough. Many people use 40# all their life at home. 55 will cause you to use more hot water. 55 will also cause you to use more FW if you boondock a lot. 40# is less pressure for leaks.

[ducksface]

We run a higher pressure pump.
70psi comes to mind.
We like the higher pressure for the shower and, well, a toilet or a cup only holds what you put in it and the shower handle is adjustable for volume from skin peeling to a trickle....

Higher pressure gives options low pressure doesn't.

[TripleGGG]

I agree on higher pressure. Coach says max pressure of 100 psi. We run 65 to 75psi. I run 70 at home.

[cavie]

Originally Posted by ducksface

We run a higher pressure pump.
70psi comes to mind.
We like the higher pressure for the shower and, well, a toilet or a cup only holds what you put in it and the shower handle is adjustable for volume from skin peeling to a trickle....

Higher pressure gives options low pressure doesn't.

you are looking for trouble with that much pressure they way these things are built

[16ACE27]

These pumps aren't rated by pressure so much as volume. Of course volume and pressure are related, but not always the way you think.

Most of these pumps have an adjustment that sets what pressure they shut off at. So you can have a 1 GPM pump with the cutoff set at 75 PSI and when there is no water flow and the pump shuts off you have 75 PSI in the pipes.

But as soon as you open a faucet the pressure drops and at the reset point the pump starts pumping again. Here's where flow capacity comes in:

That 1 GPM pump can't keep up with the flow of the faucet so the best continuous pressure may only be 15 PSI, but;
A 5 GPM pump easily keeps up with that single faucet being open and not only pumps enough water to keep up, but enough water to hit that 75 PSI cutoff and shutoff until the pressure again falls below the reset point.

So don't look at pressure, look at rated flow.

[lwmcguire]

Originally Posted by 16ACE27

These pumps aren't rated by pressure so much as volume. Of course volume and pressure are related, but not always the way you think.

Most of these pumps have an adjustment that sets what pressure they shut off at. So you can have a 1 GPM pump with the cutoff set at 75 PSI and when there is no water flow and the pump shuts off you have 75 PSI in the pipes.

But as soon as you open a faucet the pressure drops and at the reset point the pump starts pumping again. Here's where flow capacity comes in:

That 1 GPM pump can't keep up with the flow of the faucet so the best continuous pressure may only be 15 PSI, but;
A 5 GPM pump easily keeps up with that single faucet being open and not only pumps enough water to keep up, but enough water to hit that 75 PSI cutoff and shutoff until the pressure again falls below the reset point.

So don't look at pressure, look at rated flow.

Exactly and the only way to shop for a pump is flow rate first and psig next

[Porkchop]

I also have 70 psi. The pex is rated for 100. Don't know where cavie lives but I can't ever remember seeing a muni system as low as 40. "cause you to use more hot water?"
Couldn't imagine taking a shower in that.

Bill

[lwmcguire]

Well heck, just to keep this going I have never lived in any city where we had more than 50 psig. Here in this area 40-50 psig is norm and they turn it down at night to save energy and usage is lower as well, and ramp up the psig in the morning

Most midwestern towns use water towers and the head determines the psig at the homes

Other cities use pumps to augment or given the terrain full time and they use variable speed motors or in the older system simply turned on or off based on demand and target psig

In TN we did have regulators installed and maintained by the water department to limit the pressure due to the variable psig from elevation changes

they were all set between 45-50 psig

There is simply no need for high pressure in an RV unless you truly want to peel hide in the shower

You can empty a water tank in a hurry if you run an RV pump at 70 psig given you plan on opening up faucets, if not then again why do you need that much psig?

I have owned RV's since we had the little hand pumps and never yet seen one with 70 psig pump as OEM.

so you fellows with the psig pumps can sure as heck empty your water tanks in a hurry

Consistent volume is still the key at a standard range psig

[taylorbob1]

Here’s your answer

https://www.amazon.com/Seaflo-Pre-Pressurized-Accumulator-Tank

If you don’t have an accumulator tank, you’ve been missing out.
Adding this mod will make it seem like you have more pressure, while running the water almost like home.

I suggest that you try this first before you go to a higher rated pump.

[MLP]

Great flow 5.5 gpm Seaflo water pump. SEAFLO 55 Series 12V 5.5 GPM Variable-Flow Water Pump

[Porkchop]

A muni system with 40 psi? WOW!!! Couldn't live there. I live in a small town <250 people with two deep wells, no tower, but a small 5,000 gal pressure tank, ground mounted. Pressure is 61 psi. Has been since system was installed in 1968. Prior to that everyone had their own well. No one has ever complained about "excess" pressure. No one has ever had plumbing problems. You are able to run more than 1 sprinkler at a time in your yard. I know this for certain because I was the mayor for 16 years-up until we went rving. No one has ever complained about using too much water because of the pressure either. Why would I want less in my rv? By the way-we do not have water meters either. Every one pays the same amount per year=$220.

I still don't understand "use more water" When the glass is full it's full regardless of the pressure isn't it? Or have things changed because of covid?

I do agree with the accumulator tank. They work great!


Bill

[16ACE27]

Originally Posted by Porkchop

A muni system with 40 psi? WOW!!! Couldn't live there. I live in a small town <250 people with two deep wells, no tower, but a small 5,000 gal pressure tank, ground mounted. Pressure is 61 psi. Has been since system was installed in 1968. Prior to that everyone had their own well. No one has ever complained about "excess" pressure. No one has ever had plumbing problems. You are able to run more than 1 sprinkler at a time in your yard. I know this for certain because I was the mayor for 16 years-up until we went rving. No one has ever complained about using too much water because of the pressure either. Why would I want less in my rv? By the way-we do not have water meters either. Every one pays the same amount per year=$220.

I still don't understand "use more water" When the glass is full it's full regardless of the pressure isn't it? Or have things changed because of covid?

I do agree with the accumulator tank. They work great!


Bill

You don't understand what about "use more water"?

How it works if you have more pressure? Think about it: for a given size hole the more pressure you have (push) the more volume of water will go through the hole - using more water.

The concern about using more water? If you have full hook-ups - there is no concern. The concern comes in when you are boondocking and have either a limited gray water capacity, or a limited freshwater supply or both.

[ducksface]

Originally Posted by 16ACE27

You don't understand what about "use more water"?

How it works if you have more pressure? Think about it: for a given size hole the more pressure you have (push) the more volume of water will go through the hole - using more water.

The concern about using more water? If you have full hook-ups - there is no concern. The concern comes in when you are boondocking and have either a limited gray water capacity, or a limited freshwater supply or both.

I think what we're not understanding understanding is:
Run it where? A cup is a cup, a sink full is a sink full. The container dictates the total amount and the valve handle position determines the flow no matter the pressure.

My garden hose puts out 70psi.
I.dont use that to uproot and destroy the tomato plants and it doesn't overflow the container.
The valve is turned to suit the need.
The difference is while I can trickle to the tomatoes I can also spray water on the roof if needed.
Higher pressure allows more options, nothing else except the slight possibility of leakage if the pipes and fixtures won't hold 2/3 of their rating.

[RPC]

Thanks for the info. I guess I have trouble figuring if the pump can only pump 3.0 gpm does the psi make a difference other than the higher pressure in the lines when the pump is not running. Thanks again

[MLP]

Originally Posted by RPC

Thanks for the info. I guess I have trouble figuring if the pump can only pump 3.0 gpm does the psi make a difference other than the higher pressure in the lines when the pump is not running. Thanks again

If your faucet can, with pressure, deliver more than 3 gpm, then yes you need a pump that can supply more volume. If you are not getting enough flow, check the faucet screens. They may be clogging up. I will put up with less flow so long as I can get a decent shower. I installed an Oxygenics shower head and seldom need to use the on board water tank with the water pump. When I do, the shower head does the job. We use the Powermassage with the wide stream setting.

https://oxygenics.com/products/powermassage-handheld/

[16ACE27]

Originally Posted by ducksface

I think what we're not understanding understanding is:
Run it where? A cup is a cup, a sink full is a sink full. The container dictates the total amount and the valve handle position determines the flow no matter the pressure.

My garden hose puts out 70psi.
I.dont use that to uproot and destroy the tomato plants and it doesn't overflow the container.
The valve is turned to suit the need.
The difference is while I can trickle to the tomatoes I can also spray water on the roof if needed.
Higher pressure allows more options, nothing else except the slight possibility of leakage if the pipes and fixtures won't hold 2/3 of their rating.

You're adding a variable that was fixed in my explanation.

[Porkchop]

Ted=I just went and checked. I was correct. When the glass was full I shut the faucet off at both slow and full pressure. Did not use more water in either case. With your advanced knowledge maybe you can explain it better for those of us with diminished thinking ability?

Bill

[16ACE27]

Originally Posted by Porkchop

Ted=I just went and checked. I was correct. When the glass was full I shut the faucet off at both slow and full pressure. Did not use more water in either case. With your advanced knowledge maybe you can explain it better for those of us with diminished thinking ability?

Bill

Did you put the glass in the bottom of your shower and take a shower for the same period of time at both high and low pressure?

The "use more water" argument applies to taking a shower, running the sink while washing your hands or brushing your teeth or shaving as some people do; not filling a specific size container.

But if you time it, you'll find you fill that specific size container faster with higher pressure.

[Porkchop]

I'll be damned! Now I wonder why they put variable flow devices on the end of every water device in my rig? Maybe they didn't presume everyone was stupider than they were?

Bill