Cottage Lake Water Pump and Supply Questions

[Whitty21]

Hi there,

My family recently inherited my grandparents cottage, and with it, all it's problems.

Our water pump is almost dead, so we are working on an upgrade.

The pump used to sit outside under a box all summer, but we have just built a new pumphouse that the new one will be situated in.

As it is set up now, the pump (3/4hp shallow) is 30 feet from the lake, with a 10ft rise, with the pressure switch on the pump. It then goes ~200ft to the cottage, with ~40-50ft vertical to the pressure tank. I have come to learn that the pressure tank and pressure switch should be close together.

There is 30 amps (120V) of power fed down to the lake (just one circuit as it is just a 2 conductor feed).

My plan was to run a 120V sub panel at the pumphouse, to allow for a 20amp circuit for the pump, and a 15 amp circuit for lights and outlets. Having the feed be for more than just the pump eliminates the possibility for the pressure switch to be at the tank up at the cottage, correct?

Would the best option be to move the pressure tank down to the pumphouse, and have the 1" poly just drop down to a manifold up at the cottage? A second tank and a CSV valve?

The setup as of now has worked for 30+ years, but if we are rebuilding it I want it to be as correct as possible.

I hope I gave enough info, but let me know if I missed anything.

Edit: This is all in an unorganized township, so no codes or inspections, though I do want it to be correct.

Thanks in advance

 

[Valveman]

Any of those ideas will work. You can leave the tank at the house, just move the pressure switch up to the tank. Just add a new switch and wire around the switch on the motor. You can add a CSV at the pump or anywhere before the tank/switch.

With a CSV you don't need a very large tank, so it could go down by the pump. However, the pressure switch will still need to be replaced so it can be after the CSV as in one of the PK1A kits.

 

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[Whitty21]

Any of those ideas will work. You can leave the tank at the house, just move the pressure switch up to the tank. Just add a new switch and wire around the switch on the motor. You can add a CSV at the pump or anywhere before the tank/switch.

With a CSV you don't need a very large tank, so it could go down by the pump. However, the pressure switch will still need to be replaced so it can be after the CSV as in one of the PK1A kits.

The pressure tank isnt close to the electrical feed for the pump. So I think keeping the tank down in the pumphouse may be our best option. We currently have a 20ish gallon tank up at the cottage and would likely replace with something similar.

We arnt interested in going any smaller as we are off grid and don't have solar yet, so it is nice to have a bit of storage. Being off grid, the only water usage is 2 sinks and a RV toilet, so we arn't throwing heaps of water

Would a pressure tank set at 60psi be good for pushing up 50 feet? I assume there would be a decent amount of loss, but we dont need a bunch of pressure

 

[Valveman]

A 20 gallon size tank only holds 5 gallons of water, and it is not likely to be full when the power goes off. Keep a 5 gallon jug of water in a closet if you want water when the power goes off.

To go up in pressure you need a pump that can do that. You will lose 21 PSI going up 50'. If would be best to have a 50/70 pressure switch at the pump so you would get 30 to 50 at the house. For that you would need a pump that has a max pressure of about 80 PSI. You would also need at least a 10 gallon size tank, so your 20 gallon tank is fine if you have the room.

 

[Whitty21]

The pump we purchased came with a pressure switch attached. Is it fine to use that, with the pump right beside the tank, tee'd into the tank and a drain? Or would a proper tank tee be the better approach?

 

[Valveman]

It is always best to have the pressure switch on the pressure tank. However, if the pump with switch is close enough to the tank it will work fine. If the tank is too far from the switch it can cause the pump to bounce on and off rapidly on start up, which isn't good.

 

[Whitty21]

It is always best to have the pressure switch on the pressure tank. However, if the pump with switch is close enough to the tank it will work fine. If the tank is too far from the switch it can cause the pump to bounce on and off rapidly on start up, which isn't good.

If I do go with a proper tank tee with a pressure switch, do I bypass the one at the pump and just splice to the motor leads?

 

[Reach4]

A tank tee is a manifold that makes the pressure that the pressure switch sees pretty much the same as the pressure at the pressure tank.

If there is no flow in a pipe, there is no pressure loss. What you describe is one good way. The other good way is to run a sense line to the tank tee / manifold. Plug the hole that the built-in pressure switch sense line connects to in the pump housing.

I think you could set the existing pressure switch high (clockwise on the nut on the big screw is about 10 psi increase for 3.5 turns. Then use the terminal strip in the old switch to connect wires in parallel to the new pressure switch.

Convention for 240 volt is that the two hots from the breaker go to terminals 1 and 4. For 120 volts, there are different thoughts, and one is to parallel the contacts on the pressure switch to switch the hot.

Converting your pump to 240 may be easier than you think. You would need a 2-pole breaker. The old wire can usually be repurposed to carry 240.