Low water pressure in shower - old topic but what is the solution????

[bertschb]

I do hope you find a solution because keeping mama happy is quite important !

It is indeed! In my first two Grand Design 5th wheels I tried three different shower heads as well as removing/modifying flow restrictors. I also removed water filters and water softeners and tried different hoses. No difference to speak of. This new RV probably has the best performance of the three. It's actually acceptable to me. Not great, but it's fine for me. My sweet wife? Not so much. Since I can't control the water at the post, we will just have to live with what we have. For us, it's one of the few things that reminds us we're in an RV. Well, that and the fact that I hit my head once a week on something. RV's are designed for short people

[Guest]

[QUOTE=howson;n21126]

I realize pressure can increase (or decrease) at the output without changing the pressure at the source--anyone who's ever clamped down on the end of a hose with their thumb knows what happens in that instance. The restriction at the output probably does decrease overall output. That makes sense. No different than electricity (I think). Put a 10 meg ohm resistor in line with a 12v battery and you'll get very low current flow. Swap it out for a 10 ohm resistor and the current will be very high.

Howard,

When you put your thumb over the hose you are creating a low pressure region that is defined by the Bernoulli principal. This low pressure region is created by accelerating water past a decrease in cross sectional area (an effective orifice) where this is why the water can have increased speed and as a result will shoot further out past your thumb. There is also a decrease in flow where if you were capable of holding back all flow the line pressure would stabilize. This would result in the same pressure regardless of what restriction is upstream if you were able to hold all flow back with your thumb. This would be the static pressure. So a restriction such as a faucet low flow restrictor or kinked hose would reduce the flow rate as well as the pressure at the shower head. If the shower head is the restriction, the pressure would be high but the flow rate would decrease and the exit speed of the water would increase. If there is doubt, install an 0.010 orifice and turn on the faucet but shut off the shower head (if it were to seal completely). The static pressure would be the same over time. But if you open the shower valve (at the head) there would be low dynamic flow and pressure.

The oxygenics shower head mentioned by Dan is a very nice improvement. Once I opened up the restriction in the faucet and installed the Oxygenics PowerFlowRV shower head, we have been happy.

https://oxygenics.com/products/powerflow-rv/

Jim

[howson]

Guest

This is what I get for debating with engineers. I'm gonna lose. It's like debating grammar with my English 101 at college. That didn't turn out too good, either.

But I'm in for a nickle, so let's go for a dime.

How is that little gauge at the end of the faucet any different from how a gas pump works? At some fuel stations the liquid comes out like gang busters so the gallons measurement on the display increases rapidly. Some pumps are slow as molasses, so the gallons pumped display increases very, very slowly.

Isn't the little volume meter on the faucet effectively doing the same thing? Why is that "wrong" to measure? If a change is made in the plumbing and the meter registers more volume in the same time period, isn't that a good result?

[Guest]

Guest

This is what I get for debating with engineers. I'm gonna lose. It's like debating grammar with my English 101 at college. That didn't turn out too good, either.

But I'm in for a nickle, so let's go for a dime.

How is that little gauge at the end of the faucet any different from how a gas pump works? At some fuel stations the liquid comes out like gang busters so the gallons measurement on the display increases rapidly. Some pumps are slow as molasses, so the gallons pumped display increases very, very slowly.

Isn't the little volume meter on the faucet effectively doing the same thing? Why is that "wrong" to measure? If a change is made in the plumbing and the meter registers more volume in the same time period, isn't that a good result?

Howard,

I believe your correct. If there is a restriction UP Stream and you close off the exit with a valve/gauge, the pressure will be the same until you open the valve. A higher pressure pump will increase flow and pressure and the shower head and will continue to do so until the pressure becomes choked or sonic at the restriction. We do not have to be concerned with that in this case. I was only explaining some physics in how water accelerates from a restriction, and decreases flow and pressure down stream. Honestly if Brian's faucet has the tiny hole as mine in the pic, I would drill or ream it out, install a new shower head, since the factory shower head is designed to flow water through a tiny 1/8 inch diameter restrictor. Then a higher pressure/volume pump can be installed if folks are still not satisfied. This is assuming the plumbing in the rig is not kinked or restricted.

Jim

[Cate&Rob]

bertschb
Hi Brian,

Well that went "theoretical" in a hurry LOL! Who ever thought we would get into Bernoulli Principles and venturi flow in a shower discussion .

Back to basics . . . if there are too many flow restrictions built into the city water supply system, an alternative mentioned earlier would be to improve the on-board pump system and use this for showering. For the type of water pump used in our RVs, delivery volume goes down as pressure goes up. Attached is a generic pressure/volume curve for one of these pumps. This is why opening up the showerhead orifice for more volume results in lower pressure.

The pumps in our RVs are typically rated at 3 or 4 GPM . . . but, this will be at 0 back pressure. As the back pressure goes up, the available flow goes down such that at a pressure reasonable for a shower, there might be only 2 GPM available.

There are higher capacity 12V water system pumps available. These are typically used on larger boats, but would work equally well an an RV. Attached is a picture of a Shurflo twin pump rated at 3 times the capacity of the OE pump in your RV. I have no first hand experience with this pump, but part of the product description is "residential quality showers" .

If you went with a higher capacity pumping system, the 12V wiring would have to be upsized accordingly.

Something to consider is that increasing water throughput will fill up the grey tanks much more quickly.

Rob

[Canyonlight]

Brian bertschb - I turst you are using some sort of water pressure gauge regulator somewhere in your fresh water supply system when hooked up to city water. I realize that you shared in your test in a earlier post, that the difference between city water and using the pump and tank are similar. What pressure are you set at and is it possibly that your gauge may have some restriction and/or may not be actually displacing the pressure of water as the gauge is reading ? I seem to recall in the instructions when we got our regulator that this could be a real possibility.

Just a simple man with another simple idea !

Dan

[bertschb]

Brian [USER="29"]I turst you are using some sort of water pressure gauge regulator somewhere in your fresh water supply system when hooked up to city water.

Hi Dan

Yes, I've used two different adjustable water pressure regulators. Both set at 60psi. I don't notice any difference between them as far as shower flow/pressure goes.
https://www.rvwaterfilterstore.com/w...tainless-gauge

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Canyonlight]

Hi Dan

Yes, I've used two different adjustable water pressure regulators. Both set at 60psi. I don't notice any difference between them as far as shower flow/pressure goes.
https://www.rvwaterfilterstore.com/watts-263a-lf-stainless-gauge

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Yes, that's the same one I and many others use as recommended by our knowledgeable RV forum friends. We left ours at the 45 psi factory setting.

Dan

[Country Campers]

Not that this will make a huge impact on the problem or solution but here it goes.

Since we started camping , long ago , I purchased the brass water pressure regulator. This does not have any gauge and is not adjustable. I believe it is set at 40 or 45 psi. This is just a simple flow thru device. In our previous TT's it did not bother us much , only used on weekends and the showers or tub in our case was so small I could only get half way in one. In our 29RS we used the factory shower head for about a year and then purchased the oxygenics one or the other. We right away notice the "power" difference. There is also very little difference in the pump or shore water. I am thinking there is some kind of plumbing pipes that could possibly be changed to increase the "power" at the shower. Our kitchen sink has lots but our shower did not have that much.

Brian

[Guest]

[QUOTE=Cate&Rob;n21180]bertschb
Hi Brian,

Well that went "theoretical" in a hurry LOL! Who ever thought we would get into Bernoulli Principles and venturi flow in a shower discussion .

Back to basics . . . if there are too many flow restrictions built into the city water supply system, an alternative mentioned earlier would be to improve the on-board pump system and use this for showering. For the type of water pump used in our RVs, delivery volume goes down as pressure goes up. Attached is a generic pressure/volume curve for one of these pumps. This is why opening up the showerhead orifice for more volume results in lower pressure.

Cate&Rob Rob,

We are in line with our thoughts. Seemed that Howard wanted to know how this stuff works. Since we know without any doubt that the faucet is a deliberate restriction in the system, and the shower head is designed for this restriction, the basic and cost effective solution would be to bore it out and change the shower head.

To your point if the pump cannot keep up with the new higher flow capacity, a better pump may be in order. I did not find this to be the case with our rig but depending on what folks are after such as a very strong shower, higher pressure may be in order.

Also I had purchased a brass water pressure regulator (valterra I believe) a few years back where the set pressure at 60 psi did not perform well. Turned out the gage was defective where the pressure really was being skewed low. Once I replaced it with a good quality oil filled gage, the proper adjustment made a difference.

Those inline water filters (especially partially clogged) can also result in reduced flow and pressure. Ran into a fellow at the rally who I helped out with low pressure and it was his water filter.

Jim

[bertschb]

So if I want to run water from the tank using the pump for showers, I need to do the following, correct?

1- Go outside and shut the water off at the post
2- Go inside and release pressure from a faucet
3- Go back outside and switch the control valves on the Nautilus panel to tank water
4- Turn the water supply back on at the post
5- Turn on the water pump

Once the shower is done and we want to get back on city water, I would reverse this. Kind of a hassle but I would get extra brownie points if I did this each morning for my wife.

[Cate&Rob]

So if I want to run water from the tank using the pump for showers, I need to do the following, correct?

1- Go outside and shut the water off at the post
2- Go inside and release pressure from a faucet
3- Go back outside and switch the control valves on the Nautilus panel to tank water
4- Turn the water supply back on at the post
5- Turn on the water pump

Once the shower is done and we want to get back on city water, I would reverse this. Kind of a hassle but I would get extra brownie points if I did this each morning for my wife.

Hi Brian,

I'm pretty sure that I could come up with a way to do this with a remote from your recliner . . . but, lets go with the manual mode first
.
Put a valve on the RV end of city water hose and everything can be done from the Nautilus panel location.
1) Turn off this new city water valve.
2) Drain pressure using the outside hose connection at the water panel
3) Switch Nautilus valves
3) Turn on water pump with switch at Nautilus panel

BTW, if you are happier with a higher volume on-board pump, leave the water system that way and just fill the tank how ever often that needs doing.

Rob

[howson]

Moderator note: For those looking for ncitro 's question (and the subsequent discussion) regarding filling the water tank and water inside the camper simultaneously, see https://gdrvowners.com/forum/operati...-the-same-time

[bertschb]

UPDATE:

I didn't use my water pressure regulator at the RV site where we spent our summer in Bend, OR and our "water pressure" at the shower head was weak - as usual. As we traveled south this week towards our lot in Palm Springs I chose once again not to use the pressure regulator. First stop was Durango RV resort in Red Bluff, CA. Shower pressure was awesome! Almost too strong. That was the first time in our three 5th wheels at any RV park where we had a good shower experience. Decided to skip the pressure regulator at our next stop in Lost Hills, CA. Once again, the "water pressure" at the shower was excellent! Hoping to continue the trend, I skipped the pressure regulator when we arrived at our lot at Outdoor Resort in Palm Springs and once again, the shower head pressure was outstanding! So, no more water pressure regulator for me. I'd rather repair plumbing problems than have weak shower flow. Of course, that's easy to say when I have no problems and great pressure

As an FYI, I went outside a few minutes ago and installed the pressure regulator. Set it at 60psi. With water turned on at the kitchen sink, pressure dropped to 45psi and shower water flow was reduced back to where it was when I started this thread (weak).

[Calbar]

UPDATE:

I didn't use my water pressure regulator at the RV site where we spent our summer in Bend, OR and our "water pressure" at the shower head was weak - as usual. As we traveled south this week towards our lot in Palm Springs I chose once again not to use the pressure regulator. First stop was Durango RV resort in Red Bluff, CA. Shower pressure was awesome! Almost too strong. That was the first time in our three 5th wheels at any RV park where we had a good shower experience. Decided to skip the pressure regulator at our next stop in Lost Hills, CA. Once again, the "water pressure" at the shower was excellent! Hoping to continue the trend, I skipped the pressure regulator when we arrived at our lot at Outdoor Resort in Palm Springs and once again, the shower head pressure was outstanding! So, no more water pressure regulator for me. I'd rather repair plumbing problems than have weak shower flow. Of course, that's easy to say when I have no problems and great pressure

As an FYI, I went outside a few minutes ago and installed the pressure regulator. Set it at 60psi. With water turned on at the kitchen sink, pressure dropped to 45psi and shower water flow was reduced back to where it was when I started this thread (weak).

What kind of pressure regulator do you have? Some of the really cheap RV ones are really bad for reducing flow to a trickle. I use a house style adjustable regulator and soldered the hose fittings to it. The only time I have poor flow is when something has plugged one of the screens either right in the faucet or at the Nautilus connection.

Rob