I have a sets unit (tankless watre heater) my hot water temp keeps going up and down due to my pressure goimg up and down. I asked the water people I they coud raise the pressure but said it was 35psi. To 45psi. The sets unit people told me that it was my pressure and I need to fixc that 1st ; but was told about a in-line pressure pump.would this work?

Are you on well water or municipal water?

On a community water well system.

Do you need more pressure, or just a consistent pressure? In other words, would a consistent 40# work, or do you need 45+?

I need a consistent pressure. It fluctuates, that the hot water gets cold then hot. Sometimes it stays where I set the shower handle at .this is the same threw out the house.
Plummer told me but wouldn't clarify you need pressure or volume? Oh thanks for helping

If pressure is that low and the fluctuation is that broad, then you would do better to install a pressure reducing valve set at 35psi.

As for installing a booster pump, pressure as low as yours isn't going to be helped unless you install a storage tank to draw additional volume from.

I think Growler is entirely right about this. 35# seems to be a little low to me, but that might be about the best you can do. You might look into adding a booster pump with a pressure tank as you would have with a well, but be aware that you would still need the pressure valve to maintain a consistent pressure.

You more experienced guys, are you a little surprised to see 10# of pressure change in short periods on a municipal water system? That seems a little odd to me.

You more experienced guys, are you a little surprised to see 10# of pressure change in short periods of time on a municipal water system? That seems a little odd to me.

The wide disparity in pressure fluctuations would be explained by other users on the already low pressure water system drawing water at the same time.

Really, his only option here is to set up a water storage system and a booster pump.

My suggestion would be two glass lined 50 gallon tanks run in series and a 50psi booster pump located in an outbuilding somewhere, far enough away from the house that the noise of the pump won't drive him to distraction.

And before I forget, you will need an atmospheric vacuum breaker installed on the inlet of the first tank in the series.

Well I looked at some booster pumps and the one I found was a flowtec — 1560 GPH, 3/4 HP, 1in. Model# FP4815

One well guy I talked to said that this should do it and it is only needed when we take showers mainly . My only other choice is to redo the whole system and put ;spot water heaters. In each bath. Do I really need to put a water tank?
Why wouldn't the booster pump just work by itself?

Because supply isn't going to keep up with demand.

So your are talking about the volume not pressure ,or it's basically both .

What is an " atmospheric vacuum breaker".. I found 2 pressure tanks with bladders in them, will those be fine? And this booster (flowtec — 1560 GPH, 3/4 HP, 1in. Model# FP4815) will both these be fine? Thet booster is adjustable according to the specs;but the tanks are exspensive..

Izzy, Click on;Davey’s HS multistage booster system with Hydrascan control gives strong, even water pressure HS12-30HT1,HS12-40HT1,HS18-30HT1, HS18-40HT2, HS20-65-Ht2, XF14-30K1 (http://store.waterpumpsupply.com/davpumboossy1.html)
To check out in-line booster pumps. Let me knoiw what you decide. Tom

Yeah I looked at the pumps and they upgraded their the bt's #'s now.. my gpm is 55seconds a gallon and this pump will bring it to 3 gpm. ; but do I still need the 2 pressure tanks with a pump? I still looking and making sure I pick the right one. Thanks again

The bladder tank is there to provide a steady flow. I can see no advantage in having two of them. Regards, Tom

Okay so then I'll need 1 tank and I looked up the davy's pumps and found that they said the bs series was not made for whole house pressure. I looked at the "BT Torrium Control Pumps". They seem to be the one I want and how do I exactly choose what size tank and who to buy from? There is expensive; the Low Flow Packages about $1800.00 with pump ans a mini pressure tank, the holding tank is 220 gals.