- posted
18 years ago
Well design.. OK you professional plumbers
- Vote on answer
- posted
18 years ago
...
That's an undersized tank for almost any well...20 gal isn't much reserve even for just household use.
I'd not increase the shutoff pressure. This doesn't quite make sense to me...a shorter pump cycle time implies a leaking diaphragm/bladder, but that would raise air pressure as some water will displace air space. Of course, you could also have a small air leak in the valve.
Drain the tank entirely and see if there's any indication of water left (by weight, sound, temperature). Depending on whether it's bladder or diaphragm the orientation is somewhat variable.
The empty tank pressure should be 2 lb below the setpoint. Cycling the pump frequently is indication normally of the loss of volume owing to bladder failure.
- Vote on answer
- posted
18 years ago
pressurize to
hurting them
thanks,
There should be no problem in raising the pressure as long as the pump is rated for it and it almost assuredly is.
Yes, drain tank, decide what pressure you want the cut-in and pressure to 2psi below that. Maintain the 20psi differential between cut-in cut-out. There are controllers available that provide a constant pressure but I haven't used nor worked on them.
Common settings are (but you don't have to stick to them)
20-30 - IMO too low but would be useable for house use only. Poor shower performance. 30-50 - about minimum if you are irrigating IMO. That is what I have 40-60 - Max recommended for residential. Higher pressures cause wear/tear on fixtures.The pre-charge is only there to provide a bubble of air to be compressed. It has no effect on delivered water pressure. The 2psi below cut-in optimizes the pump run time for whatever pressure setting you are using. It results in the minimum start/stop cycles. The starting is what causes most wear on a pump.
Of course there if the pump/well is much lower/higher than the house you have to make allowances for that. .43 psi per foot difference. No change in pressure settings if the tank is in the house.
Harry K
Harry K
- Vote on answer
- posted
18 years ago
- Vote on answer
- posted
18 years ago
Some people do a secondary unit. Pump pushes up to a nonpressurized reservior, then another pump delivers from that to a pressure bladder unit. That's essentially what happens with a cistern, too. I know of one that has a 500 gallon tank in their basement, and they have a really small pump delivering from their well into a 1/2" line so that it is less likely to cause cycling problems to the well. The tank has a float microswitch that calls for water when it has dropped a hundred gallons. They say they have all the water they want. BTW, they also routed outside spigots and toilet flushing water so they are not chlorinated.
- Vote on answer
- posted
18 years ago
The "feet to water" is the vertical distance from the gauge (pressure tank) to water level in well (typically while pumping). You have not mentioned how far down it is from ground surface to water surface, which may be close enough, but can vary over time (dry years or over pumping). If you have a pump curve, it will show X gpm @ Y feet of head. To figure out X you need to know Y. Ignoring piping head loss for now:
Y = (psi_gauge_press * 2.31) + vertical_ft_from_gauge2pumping_H2O_level
When my sister's family built their house which had roughly a 200' well, they used a 1 hp pump and 82 gal pressure tank (set 40-60 psi). You could flush a toilet without kicking on the pump. You could open all 3 spigots outside full blast and the pump maintained 45 psi.
(snip)