Shower pressure improvement

[DeltaRon]

At a suggestion of a friend, when hooked up to water supply, I also ran the water pump and almost doubled my water pressure. Just wondering if others had tried this?

[Al and Missy]

Typically with both of my trailers and three different shower heads over five years the water pressure at campsites has always been greater that from my water pump. Was this at a campsite that had low pressure? If the experience you described is typical, you may have a defective pressure regulator on your fresh water input.

Al

[DeltaRon]

No. What I’m saying is that if you run both, water pump and city water at same time, your pressure is increased significantly. Pressure regulator is not important.

[rmkrum]

Only if the water pump generates ALL that pressure. The city water inlet does not, repeat not, feed into the input of the pump. It feeds into a check valve that, when the pump runs at a higher pressure than the inlet, will cut off the flow of city water. The pump only draws water from your fresh tank.

If the city water is that low pressure, just fill your fresh tank and run on the pump.

This “run the pump to boost city water pressure” is Airstream legend, not plumbing facts...

[AlinCal]

So if city water pressure is 65psi and my pump puts out 45psi don't I end up with 110 psi?

[rmkrum]

Nope. The best you can do in that situation is about 65 pounds. The pressures don’t add. Reality is the pump won’t even run. The pressure switch cuts it off at 45 pounds (or greater), in this case.

The electrical equivalent is 65 volts on one side of a diode, and 45 on the another diode feeding the same load resistor. Most you will see is 65 volts in the circuit. There will be no current (flow) from the 45 volt side

[Al and Missy]

Originally Posted by DeltaRon

No. What I’m saying is that if you run both, water pump and city water at same time, your pressure is increased significantly. Pressure regulator is not important.

Yes, it is, for two reasons. 1. The pump supplies somewhere around 40 psi, and it has a pressure cutoff switch. When you use water from the tank by opening a valve, the pressure drops and the pump turns on. When you close the valve, the pressure rises (to around 40 psi) and the pump turns off. So the pump will not supply more than the pressure set by the cutoff switch. 2. The fresh water inlet has a pressure regulator valve, probably again at about 40 psi, the nominal operating range of the trailer's water systems. If the pressure from the freshwater inlet is higher than the valve's setting, it reduces the pressure applied to the trailer.

Taken together, if turning on the pump increases the pressure at the faucet, it is because the pressure available on the trailer side of the pressure regulator is lower than the pump output pressure. I'll bet you an adult beverage of your choice that your pressure regulator is bad or your fresh water inlet is obstructed somehow.

Al

[rmkrum]

Or the city water supply pressure is lower than the inlet regulator pressure setting. There is also a little check valve built into the city water inlet to keep water from spewing out the inlet if you run the pump without water connected to the inlet.

I have a regulator at the city water supply with a gauge on it at the end of my hose. I also have a gauge plumbed into my water system, just to keep an eye on what the pump and the cheap plastic regulator on the city water inlet is doing to me.

Yup, Overkill Engineering attitude. If I can’t measure it, I don’t know what’s really going on.

And that gauge will indicate no more that the pump outlet pressure or the output of the cheap inlet regulator. My pump runs up to about 45 pounds max, and the inlet will hit a max of whatever I set on the regulator on the supply from the campground—usually 40-45 pounds to keep from blowing out the fresh water hose. I never see more, only whichever of the pump or my portable regulator is set higher. I basically don’t trust the cheap plastic regulator on the city water inlet.

[DeltaRon]

Understand all comments. Now, with city hooked up and fresh water in tank, start your shower. With shower running, start your water pump and watch as your shower pressure increases. Why is my question?

[SteveSueMac]

Originally Posted by DeltaRon

Understand all comments. Now, with city hooked up and fresh water in tank, start your shower. With shower running, start your water pump and watch as your shower pressure increases. Why is my question?

Maybe the city water pressure is below 35?

Here’s a snip from my trailer’s user manual that explains it:

[DeltaRon]

Thanks. Water pressure reading from city is 50 psi. Still the shower pressure increased when I turn on pump. Seems strange to me. I’ve tried this numerous times at different campgrounds and it always works.

[daleyocum]

Originally Posted by DeltaRon

Thanks. Water pressure reading from city is 50 psi. Still the shower pressure increased when I turn on pump. Seems strange to me. I’ve tried this numerous times at different campgrounds and it always works.

I’ve always done the same, turned on the pump when we take showers, because of the increased pressure. I thought what was happening was it was drawing water from both sources but now I’m thinking it is just pulling from the fresh tank and our regulator is defective or there’s a clog.

That brings me to my question. Is the regulator behind the fresh water city input on the side of the trailer or somewhere else?

[rmkrum]

The factory installed regulator is a clear plastic part on the back of the city water inlet if it’s original.

Yup, if running the pump increases pressure, you are using the contents of your fresh water tank. Many times, the pun is set to run at about 60-65 pounds or so.

That’s why I suggest that it’s easier to just fill the tank in a campground with low water pressure, and just run the pump.

As a side note, always use a filter either on city water, or filling the tank. It helps keep fine particles and other nasty stuff out of your water system.

[link2dks]

Originally Posted by DeltaRon

Thanks. Water pressure reading from city is 50 psi. Still the shower pressure increased when I turn on pump. Seems strange to me. I’ve tried this numerous times at different campgrounds and it always works.

I'm taking a wild guess here. You say the city water pressure is 50psi so I'm assuming you have a pressure regulator at the campgrounds spigot. What you or any of us don't know is what is the pressure after the trailers pressure regulator unless you have installed a pressure gage down stream from that regulator.

My guess is your pump is providing more pressure than your trailers city water regulator is allowing therefore increased water pressure when you turn the pump on.

Dave S

[Al and Missy]

Originally Posted by link2dks

...What you or any of us don't know is what is the pressure after the trailers pressure regulator unless you have installed a pressure gage down stream from that regulator.

My guess is your pump is providing more pressure than your trailers city water regulator is allowing therefore increased water pressure when you turn the pump on.

Dave S

Which is what I said twice.

Take the pressure gauge that was used at the city water inlet and attach it to your trailer's external faucet, or to an internal faucet. What is that pressure?

Al

[rmkrum]

That’s why I have a pressure gauge on the internal system as well. Mine gets up to about 60 on the pump.

[Al and Missy]

Originally Posted by Al and Missy

Yes, it is, for two reasons. 1. The pump supplies somewhere around 40 psi, and it has a pressure cutoff switch. When you use water from the tank by opening a valve, the pressure drops and the pump turns on. When you close the valve, the pressure rises (to around 40 psi) and the pump turns off. So the pump will not supply more than the pressure set by the cutoff switch. 2. The fresh water inlet has a pressure regulator valve, probably again at about 40 psi, the nominal operating range of the trailer's water systems. If the pressure from the freshwater inlet is higher than the valve's setting, it reduces the pressure applied to the trailer.

Taken together, if turning on the pump increases the pressure at the faucet, it is because the pressure available on the trailer side of the pressure regulator is lower than the pump output pressure. I'll bet you an adult beverage of your choice that your pressure regulator is bad or your fresh water inlet is obstructed somehow.

Al

Change all the 40 numbers above to 55 and it will be as in my trailer. I mis-remembered the pressure of my pump - it is 55, not 45. The physics still applies. If turning on the pump increases shower pressure, the pressure provided by the pressure regulator connected to the city water inlet is less than 55. Typical residential pressure is 70-95. Some campgrounds have pressure regulators on their systems, some do not.

Al

[rmkrum]

Yup. Exactly.

I tend to regulate campground pressure to around 40 pounds to protect my city water hose from bursting in the heat. Plastic or vinyl gets soft as it warms.

[smithcreek]

Question, let's say you are only using the pump. When you turn on the shower, the water pressure in the line drops, which causes the pump to come on. Specifically when using the shower, do most pumps stay on continuously or do they cycle on and off?


I'm asking because our trailer was one built during a short period where they used an oddball Shurflo Extreme variable speed pump, so it stays on all the time. What about the standard Shurflo Revolution pump most trailers have?

[rmkrum]

Mine tends to stay on continuously when we take showers. Takes a lot of water flow to run the tankless water heater as well. We turn the hot on full blast then adjust cold for the right temperature. DW loves her hot showers and that’s why we went to a tankless hot water system. (Happy wife, happy life)

It cuts on and off a lot when we flush the toilet or wash hands. I’m going to dig into the dank, dark recess where the pump hides and try to install an accumulator tank to smooth it out.

My pump is not variable speed by any means. I.e., noisy when running...bangs and vibrates the plumbing a lot. Accumulator and flex tubing on input and output should help a lot.