I have a two pump system on my 3 story house. One pump draws from the well and fills a large aerator/holding tank at ground level. A second pump draws from that aerator/holding tank and pumps the water thru a pressure tank and into the house. My question involves the second pump and pressure tank. Right now according to the specifications on the second pump it is a 1hp jet pump putting out around 15gpm and the pressure switch is set at 35/55. There is no real performance issues, pressure wise, but I am looking to re-vamp and relocate the system. The pump will be within 10 ft of the holding tank and >10 ft from the location of the pressure tank. There are three people living in the house and there are 12 water outlets (toilets, showers and sinks). Only 6 get used regularly. Would a centrifugal/sprinkler pump work for this application? What size pressure tank would be the best? I see pump set ups that come with a small bladder tank attached..would this work for my application? I understand that there are tons of variables that can be used to calculate the exact specs of what is needed, but I am just looking for a ballpark answer for the pressure tank. What would your design be?

 

If what you have is working..... why not just move it ?

 

I am moving the system. The existing tank is an old fiberglass tank that was put in years ago to supposedly increase the water pressure. It is a really large tank, over 5ft tall and 3ft diameter. It has a removable rubber bladder, but the bladder in it has been ruptured for quite a long time. I contacted the manufacturer for a replacement bladder and they no longer make that style tank and to replace the bladder would be as expensive as buying a new pressure tank.The pumps now are outside and have been in the weather for a few years so I am going to replace them and move them into the garage. So I was looking for some suggestions on pumps and pressure tanks.

 

So, no suggestions from anyone?

 

What water pressure do you want? Pick a pump that can comfortably provide the flow volume while maintaining that pressure. Many sprinkler pumps are designed for lower pressures like 30 psi while many people want closer to 60 psi for an invigorating shower.

Choosing a pressure tank depends on how often you want the pump to cycle on and off. A larger tank means the pump will cycle less frequently. If it is set up properly you'll never know the pressure tank is there, but all a pressure tank does is smooth out the flow and minimize cycling of the pump. It does not have anything to do with your water flow volume or pressure.

 

Thank you for the response...I have decided to put in new pumps of the same model and size of the old ones and go with a 20 gallon pressure tank...

 

Wm-

I think 20 gal is way too small. Your old pressure tank at 5’H x 3’ Dia. would be about an 80 gallon tank and would have a drawdown of about 25-30 gallons whereas a 20 gal tank would have a drawdown of only about 8 gallons. Your pump will come ON/OFF much more often with the 20 gallon tank and the start/stop is what wears the pump out. Pump manufacturers recommend your pump run for at least one minute when it comes on.

If your current pump outputs more than 8 gals/min. you can see that your pump will run less than a minute with a 20 gal tank. I believe the current wisdom is the bigger the tank the better.

 

How about a 1hp/18gpm pump-->50 psi cycle stop valve--> 20gal pressure tank.

 

I’m no expert but the cycle stop valve then is a different story. This seems like a really good tutorial on the cycle stop valve.

https://www.youtube.com/watch?v=LPIUufWjbic

Is it worth it? I don’t know, but maybe one of the pros will jump in. It does add some complexity to the system and obviously another point of failure.

 

Thanks, I saw that exact video..very good info on the CSV...the company offers models that are preset at a specific psi and are non adjustable..those much cheaper than the fully adjustable ones...but, as you mentioned, another point of failure is a good point...the project has been put on hold for a few weeks, but Im still interested in opinions...thanks