Help, pressure tank size

[Stmar]

Of course tank went out on Labor Day. Tank is a 62 gallon, that replaced a smaller tank and it could have been just what they had on hand at the time. Today my choices are limited; 40, 50, 85 gallon tanks. Which would be acceptable. It would be hard to get a larger tank, the 85, into our crawl space. Would the 50 be okay? 3/4 horse pump, 40/60 pressure switch.

 

[Tughill Tom]

I only have a 20Gal on my 3/4HP system and no issues. I'd go with the 50 just to be on the safe side.

 

[William1]

Depends (of course!!!). How often does your well pump cycle now? The bigger the tank, the less it cycles but the longer you are at the low end of the pressure range (and longer at the high end). I have a 50 gallon. Remember, it does not hold 50 gallons of water, actually about 1/2 that, the rest is air. Mine cycles a few times a day. when I got my place, it had a ridiculous five gallon tank!!!
If you have a lot of people in the house, do multiple loads of laundry,many showers every day, opt for larger.
BTW, you do not have to have one large tank, you can daisy chain them. IE, you could get a 40 and add a second 40 later if you felt the pump was running too much.

 

[CaveCreekRay]

The smaller tank just means your pump has to cycle more to keep the pressure up. That means more wear on your motor contactor and the pressure switch. Could you stack two 40's or 50's down there?

 

[SidecarFlip]

If you are referring to a captive air tank (bladder tank). bigger the better. Bigger the volume of the tank the less the pump cycles, the longer it and the switch gear lasts. I have a 60 on mine and just the 2 of us. 1.5 horse 22 deep well pump, 130 feet downhole. Get the largest you can get in the alloted space.

 

[North Idaho Wolfman]

Depends (of course!!!). How often does your well pump cycle now? The bigger the tank, the less it cycles but the longer you are at the low end of the pressure range (and longer at the high end). I have a 50 gallon. Remember, it does not hold 50 gallons of water, actually about 1/2 that, the rest is air. Mine cycles a few times a day. when I got my place, it had a ridiculous five gallon tank!!!
If you have a lot of people in the house, do multiple loads of laundry,many showers every day, opt for larger.
BTW, you do not have to have one large tank, you can daisy chain them. IE, you could get a 40 and add a second 40 later if you felt the pump was running too much.

Are you sure you don't have a digital well?
Digital wells change the speed of the pump for the demand load, the require a smaller tank and do not use the tank in the same fashion as the old pump up system.
They are much cheaper to run that a standard pump setup as they run the pump per demand, not full out all the time, they are about 75% more efficient.

You can tell by the controller as it won't be a simple on off switch.

 

[Stmar]

Thanks for the input. After looking at the 85 gallon and the specs we went with the 50. Good pressure, the old one must have been loosing pressure before it failed because we can tell the difference. Interesting concept adding an additional tank in series, will keep that one in my memory bank for future consideration.

 

[Stmar]

Searching for a locally available water well pressure tank brought up an interesting revelation. Most of the stores; TS, Home Depot, Menards all stocked 44 and 85 gallon tanks. Any theories on why only these choices in the larger size tanks? After more research I think the 50 that I found is the best fit, the 44 probably would have worked also.