Am I A Good Candidate for Boost Pump on Public Water?

[sgiorgianni]

Hello,

We have been having trouble with low water pressure since we purchased the house 2 years ago. We are unable to enjoy taking 2 showers at the same time or even take a shower and run the washing machine. We finally replaced the old water softener with a new one (and a piped bypass so we could test everything), the town upgraded the meter, and everything looks right and there isn't any obstructions but we still are unable to get adequate flow for 2 enjoyable showers at once. If I bypass the softener/filter it doesn't improve the situation by much. I think we are a candidate for a boost pump aka Scala2, but I find the whole pressure vs volume issue beyond my grasp.

My details:
House built in 1996, 2 bathrooms 2nd floor, water meter in basement
3/4 copper coming into house and through meter through the house (I'm sure they drop to 1/2 at some point)
51 PSI max possible for the water main we are on (called the town)
40 PSI at our meter
5 GPM flow at a spigot right off the meter
3.5 GPM flow from 1 tub (PSI drops to 36)
2.8 GPM flow from one of the tubs with 2 tubs running (PSI drops to 29)

Is a Scala2 boost pump an adequate solution for us? I feel like we have a pressure issue, not a volume, but I still don't grasp the specifics and need an expert!

 

[Valveman]

It does sound like you have plenty of volume since you still have 29 PSI with 2 tubs running. But stay away from the hype of those Scala2 things and get a regular long lasting jet pump and a PK1A to control it. Getting the pump the company spends the most money advertising is like getting stuck with a Tar Baby. They make the all in one and does everything you need pump sound inviting because it makes them the most money, which of course will cost you the most money, especially in the long run. I would get something like a Goulds J10S and a PK1A. Set the pressure switch for 50/70 and the CSV for a constant 60 PSI in the house. Even with two showers going the 60 PSI constant will be so strong you will no longer even need soap in the shower.

 

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[sgiorgianni]

Thank you for the info! I did some reading, cancelled my order for the Scala2, and ordered a PK1A kit! Could you guys help me figuring out which pump to get?

You recommend a 1hp, that’s a good size? Some charts seem to say 3/4hp, but I’m new at this.

When shopping for a pump to boost public water pressure, I am just looking for a “shallow well” jet pump right?

Why that specific J10S pump? Are there features I should be looking for?

 

[Reach4]

I would think that the J5S would have enough oomph to boost your city water. In between the J5S and the J10S is the J7S.

https://www.lockewell.com/pdf/goulds/j-series.pdf

 

[Valveman]

The J5S is probably large enough. However, with a CSV you can install as large a pump as you think you need for max flow. The CSV1A as comes in the PK1A kit will make it work like a small pump when small amounts of water are being used. With the J10S you just have the ability to use twice as much water at a time, like when you have company. No one will have to stagger their shower times.

 

[sgiorgianni]

Thanks, I got a Cycle Stop Valve and a J10S. I just got it installed but it isn't working that well though.

I don't have a check valve. I thought the CSV would act as one and I thought I had one in the pump (Gould J10S)? The pressure builds up to where it's supposed to be and then drops off back to the municipal PSI over 10-20 seconds. Looks like I'll be installing one tomorrow.

Most importantly, it doesn't keep up the pressure when running 2 showers, which was the entire point of this. With 2 showers running, it only puts out 35-40 PSI. The intake coming in from the street is showing 30 at this point. Max of 7PSI increase over no pump. Not satisfied, any idea?

 

[Reach4]

Is this powered by 230 or 115 volts?

I wonder if cleaning the jet nozzle with a wire would help if the voltage is right.

I would consider putting a Winters Instruments PCT330 -30 inHg 60 psi gauge.

on the input pipe. It can measure both pressure and vacuum.

https://www.supplyhouse.com/Winters-Instruments-PCT330-4-1-2-PCT-Contractor-Pressure-Gauge-30Hg-0-60-PSI
The picture on that page does not match the gauge.

 

[sgiorgianni]

230 volt on a dedicated circuit.

I have a gauge right off the meter before the pump, and that one is reading ~30psi.

What does it look like when a pump runs out of flow? Does pressure drop to ~0? Is there some other way to tell if it’s the pump or if it’s the supply?

 

[Reach4]

230 volt on a dedicated circuit.

I have a gauge right off the meter before the pump, and that one is reading ~30psi.

What does it look like when a pump runs out of flow? Does pressure drop to ~0? Is there some other way to tell if it’s the pump or if it’s the supply?

How far is that? There may be substantial restriction after that gauge and before the intake of the pump.

Negative pressure = a vacuum. 30 inHg of vacuum is a very strong vacuum that you will not achieve normally, even with 100% blockage. That gauge that reads the vacuum or pressure would tell the story.

Clean the jet nozzle. That is what the plug under the intake is for. Hope that is the deal rather than the line from the water meter being kinked/crushed....

 

[sgiorgianni]

I will try cleaning the jet nozzle.

Water meter and entrance into foundation is right next to the pump itself. The pressure gauge on the meter is right next to the pump, there is no way that there is a restriction between the two.

Ill let you guys know, thanks

 

[Valveman]

Thanks, I got a Cycle Stop Valve and a J10S. I just got it installed but it isn't working that well though.

I don't have a check valve. I thought the CSV would act as one and I thought I had one in the pump (Gould J10S)? The pressure builds up to where it's supposed to be and then drops off back to the municipal PSI over 10-20 seconds. Looks like I'll be installing one tomorrow.

Most importantly, it doesn't keep up the pressure when running 2 showers, which was the entire point of this. With 2 showers running, it only puts out 35-40 PSI. The intake coming in from the street is showing 30 at this point. Max of 7PSI increase over no pump. Not satisfied, any idea?

Which CSV did you get and has it been adjusted? With 30 PSI coming into a J10S pump you should have good pressure. Of course you will need a check valve to make it work properly. But the check valve only matters when the pump shuts off. When using a 40/60 switch setting, the CSV should be adjusted to hold 50 PSI constant while running one shower. You should still have like 48 PSI with two showers running.

 

[sgiorgianni]

Is this powered by 230 or 115 volts?

I wonder if cleaning the jet nozzle with a wire would help if the voltage is right.

I would consider putting a Winters Instruments PCT330 -30 inHg 60 psi gauge.

on the input pipe. It can measure both pressure and vacuum.

https://www.supplyhouse.com/Winters-Instruments-PCT330-4-1-2-PCT-Contractor-Pressure-Gauge-30Hg-0-60-PSI
The picture on that page does not match the gauge.

Quick question: Trying to understand vacuum gauges. If I have positive pressure coming into the pump (pressure from the main), will my vacuum be 0?

I show some pressure on my gauge on the suction side of the pump, this indicates that I am not “sucking” from the main IE pulling a vacuum...?

 

[Reach4]

Quick question: Trying to understand vacuum gauges. If I have positive pressure coming into the pump (pressure from the main), will my vacuum be 0?

Talking about a combination gauge, such as the one I suggested above... https://www.mcmaster.com/vacuum-pressure-gauges/pressure-and-vacuum-gauges-6/ talks some about combination gauges. A vacuum is relative, in this case, to atmospheric pressure.

With the pump not on and no water being drawn, I expect the gauge to read about 30 on the clockwise side of zero. When you start using water, the needle will turn CCW more and more. If there is a lot of flow, the pressure can go below zero. We call that a vacuum.

You expect the pressure on that gauge will stay positive (above zero) in all cases. I am not so sure. Why? IMO, either your pump is defective, flow is a lot bigger than expected, or the pressure at the pump goes to less than atmospheric pressure -- a vacuum on the gauge.

But no, if there is positive pressure into the pump at some point in time, the needle will be clockwise from zero -- not a vacuum. Now do you have positive pressure? The gauge would be my indicator.

 

[Valveman]

If the pressure goes to zero or negative you are sucking more water than you can get from the mains.

 

[sgiorgianni]

OK I have put a pressure/vacuum gauge on the intake to the pump. Also makes it easier to read being oil filled, an unexpected bonus.

Did a lot of experimentation, here is my results!

-The pump never pulls a vacuum which tells me that the flow from the street is unimpeded. If I drain the sprinkler system and open it wide, the pump can push water into the system with no restriction and almost as easy as discharging into the air. Then for just a moment the pressure goes to 0, the pump cavitates quite loudly, and it unmistakably runs out of flow. This pulls about 18 GPM, the max that a 3/4 inch copper pipe at 40PSI should really handle. Seeing this, I am good with the flow into the house from the main.

-I had to fiddle and experiment with the valves and CSV allot. Something I didn't notice before, should have known, and know now is that the more flow there is the greater PSI drop there will be. So when I flow 10 GPM through a water softener and 2 filters, a 15-20 PSI drop is normal. What I ended up doing is tuning the CSV to 65-68PSI and the pressure switch to ~58-72 PSI. Both measured at a gauge *after* the filters at about 2GPM. Fun fact, if you remove the small spring from the pressure switch you get about a 18 PSI range and nothing narrow-er.

So now, normal usage, with the pump off I hold around 70-72 PSI in the house. Pump kicks on during normal usage and it will hold 65 PSI during normal usage. 2 showers running it will only drop a few PSI(6 GPM). With a tub and shower running the PSI will drop to 55-60. Two tubs drops to 50.

This is noticeable, but still enough pressure to allow the showers hold their temperature well and be an acceptable pressure. You can barely detect a toilet flushing while taking a shower and this is when expecting it. And you can take 2 showers at once with adequate pressure. Which was the true goal.

I was hoping for 2 tubs running full bore and maintaining 65 PSI, but I accept this is a limitation of running both off a 3/4 copper trunk and shrinking to 1/2 when it branches off. I feel good about the system I have setup, I feel its running acceptably, and I thank everyone for their help!