I recently purchased a house with a well that's set at 30/50psi and am not happy with the pressure as my last house was 40/60. I know how to adjust this so that's not an issue but I am curious about the pump handling it. The well is 225' and has a 1/2hp 240v pump. Does anyone see an issue with this size pump handling the pressue increase?
Water pressure vs pump size
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LLigetfa
DIYer, not in the trades
It is not about the depth of the well or the HP of the pump. It is about the depth to the water surface and the number of stages on the pump.
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LLigetfa
DIYer, not in the trades
Plot the curve of the pump by measuring the GPM at the higher pressures to see how close you come to deadheading the pump.
I think you want some margin. So for 40/60, I would like to see the pump deliver 65. Then back off to 40/60.
It would be best to raise the air precharge before raising the pressure switch setting.
Typically 3.5 turns CW on the nut on the big spring raises both cut-in and cut-out by 10 psi.
LLigetfa
DIYer, not in the trades
I think a 5 PSI margin is cutting it too close. I would be more comfortable with a 10 PSI margin.
Unfortunately I don't have the info for the depth to the water surface or the number of stages on the pump, the well and boring report only lists the depth and the pump manufacture/HP/GPM so I don't know the model.
Can you explain a little more what you mean by PSI margin? I may be over my head with this.
Can you explain a little more what you mean by PSI margin? I may be over my head with this.
Can the pump pump up to 70 psi if you keep it running? For 40/60, that would give a 10 psi margin.
LLigetfa
DIYer, not in the trades
The GPM achieved for a particular HP is done by the number of stages. You don't need to know the number of stages if you already know the GPM. Look up the tables for that pump and it will tell you how much total head it has. It will also show the GPM at the various depths so trending the GPM/pressure should let you reverse calculate the depth.
Tighten the large adjustment in the pressure switch almost all the way down. If the pump will build up to 70 PSI, then you can turn the pressure switch back down to 40/60 to be safe.
Even at 40/60 or even 50/70 you still have 20 PSI between high and low pressure as the pump is cycling. Even if the shower is good at 55-60 PSI, it will seem dismal when the pressure tank is draining down to 40 before the pump comes on. This is why "constant pressure" has become so popular for home water systems. With a 40/60 pressure switch a CSV would hold 55 PSI constant while taking a shower, even if showering for a month. 55 PSI constant in the shower will seem so much stronger than without a Cycle Stop Valve as the pump will be cycling itself to death between 40 and 60 over and over, which also makes for weak shower pressure.
Even at 40/60 or even 50/70 you still have 20 PSI between high and low pressure as the pump is cycling. Even if the shower is good at 55-60 PSI, it will seem dismal when the pressure tank is draining down to 40 before the pump comes on. This is why "constant pressure" has become so popular for home water systems. With a 40/60 pressure switch a CSV would hold 55 PSI constant while taking a shower, even if showering for a month. 55 PSI constant in the shower will seem so much stronger than without a Cycle Stop Valve as the pump will be cycling itself to death between 40 and 60 over and over, which also makes for weak shower pressure.
Even before adjusting anything for test, another clue would be to watch how much pressure increase there is in the last 10 seconds of running compared to say the first or middle 10 seconds. If the pressure is rising almost as fast at the end, then the pump would have more headroom for running at higher pressure.
If the last 10 seconds of a 60 second run only gains 2 psi, then it is slowing down. Setting the pressure switch higher is probably not going to be a good idea.
For a pure test, there would be no usage once the pump kicks on, but it seems to me that by taking a movie of the gauge during a shower would be informative too. So this would be an alternate indication to maybe try before moving on to the test described above.
If the last 10 seconds of a 60 second run only gains 2 psi, then it is slowing down. Setting the pressure switch higher is probably not going to be a good idea.
For a pure test, there would be no usage once the pump kicks on, but it seems to me that by taking a movie of the gauge during a shower would be informative too. So this would be an alternate indication to maybe try before moving on to the test described above.
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