Is it ok to for a sub to pump directly into pressure tanks?

[Jfharper]

I'm assuming it is. But I thought I would ask if it was ok and what things to watch out for.

The long story:
Currently, my holding tank is leaking at the outlet. The holding tank is on a platform about 25 feet off the ground which make is challenging to work on. The leak is pretty bad, but my sub still only comes on and runs for 35 min and then is off for ~1:15 (h:mm) because I irrigate some trees, as apposed to ~25 min on and 1:30-1:40 off before the holding tank starting leaking.

IF the pipe breaks at the outlet rendering my holding tank useless, my plan is to directly pump from the sub into my two pressure tanks to get by while I figure out how to approach the holding tank fix. I have a T at the top of the well that is already hooked up to the pressure tanks but a gate valve closes it off currently, so the sub only fills the holding tank via a float switch. There is a gate going to the holding tank, so I could close that. I could manually turn on the sub to fill the tanks, watching a pressure gauge to turn off at 60 PSI, and we can ration water in the house (I would turn off all irrigation) while I'm repairing or replacing the holding tank.

I'm thinking this might be a good time to pull that holding tank down and take that platform down, because it just makes things more difficult to work on and we really don't benefit that much from the ~20 PSI gravity feed, either when the power goes out, and we don't use gravity feed irrigation which there were a few pipes setup for.

I know I could hook up a pressure switch to the sub relay to handle turning it on/off automatically, but I'd hate to have something go wrong and my new sub I just installed go out. Maybe just a bit paranoid, but I don't mind doing it manually just to avoid a second problem when I already have one problem to deal with first.

So, what should I watch out for with the sub to the pressure tanks fill up? TIA.

 

[Reach4]

There is a gate going to the holding tank, so I could close that. I could manually turn on the sub to fill the tanks, watching a pressure gauge to turn off at 60 PSI, and we can ration water in the house (I would turn off all irrigation) while I'm repairing or replacing the holding tank.

That works. You could also maybe control the submersible with the pressure switch that normally controls your pressure pump that gets fed from the above-ground water tank.

 

[Sponsor]

 

[Jfharper]

That works. You could also maybe control the submersible with the pressure switch that normally controls your pressure pump that gets fed from the above-ground water tank.

You know, I just looked at it, and think I might do that...it looks pretty easy. Basically, disconnect the booster pump from pressure switch and run a wire from one side of the pressure switch to the float relay switch.

 

[Valveman]

If your well pump will make enough flow and pressure, you don't need a storage tank. If after installing the pressure tank and pressure switch on the well pump you find it can't keep up with demands, you will need to replace the storage tank.

 

[Valveman]

Also if you do pump the well dry a Cycle Sensor would shut the pump off before the pump is destroyed.

 

[Jfharper]

From the image from this post:
https://terrylove.com/forums/index.php?threads/help-identify-pump-switch.75877/#post-557189

I'm assuming I would disconnect the black (C1) and white (L1) which are from my float switch, and connect a hot (when on) from my pressure switch to C1 . I believe this is how it would engage this 2-pole contactor (I think that is what it is called) and turn on the sub.

Then at 60 PSI, the hot would disconnect at the pressure switch and the power relay would turn the sub off.

Do I have this correct?

 

[Jfharper]

If your well pump will make enough flow and pressure, you don't need a storage tank. If after installing the pressure tank and pressure switch on the well pump you find it can't keep up with demands, you will need to replace the storage tank.
View attachment 47632

Forgot to mention, the new sub I just installed is a 1/2 HP 16 GPM. I would think it would keep up, if we only run 1 shower at a time and offset laundry and dishwasher, which are new and more water efficient.

But I understand what you are saying...I think when I water the grass, and have irrigation on it is nice to have the storage tank and do think it helps. I'll have to think about what I want to do...but thanks for your note.

 

[Jfharper]

Also if you do pump the well dry a Cycle Sensor would shut the pump off before the pump is destroyed.

That has been on my "to get" list for about 5 years now. Might be a good excuse to pull the trigger, just so I have $100 insurance.

I thought they were $100...maybe I was wrong.

 

[Valveman]

There is a wiring diagram on this drawing.

 

[Jfharper]

There is a wiring diagram on this drawing.
View attachment 47633

Thank you.

 

[Jfharper]

If your well pump will make enough flow and pressure, you don't need a storage tank. If after installing the pressure tank and pressure switch on the well pump you find it can't keep up with demands, you will need to replace the storage tank.
View attachment 47632

Trying to determine if my new well pump has enough pressure...it is a Grundfos 16S05-5 with a MS402 motor. The sub sits at 80 feet and I think my water level is around 50 feet now that California has gotten rain flowing from the Sierra's. I believe these are the links (I don't know how to read these curves):
Pump:
https://product-selection.grundfos....tid=GMA&productnumber=10013605&qcid=393366885

Motor:
https://product-selection.grundfos....detail.html?custid=GMA&productnumber=79192006

 

[Reach4]

Trying to determine if my new well pump has enough pressure...it is a Grundfos 16S05-5 with a MS402 motor. The sub sits at 80 feet and I think my water level is around 50 feet now that California has gotten rain flowing from the Sierra's.

This will be easier than curves. It looks like you would need to set the pressure switch to maybe 20/40 PSI depending on the water level. Make sure that the pump does not take a couple minutes to do the last few psi before shutoff after using water. You want some margin.

I think you can do two showers at once, but have the people start and stop the water use slowly enough to get the other person time to react if needed.

 

[Jfharper]

This will be easier than curves. It looks like you would need to set the pressure switch to maybe 20/40 PSI depending on the water level. Make sure that the pump does not take a couple minutes to do the last few psi before shutoff after using water. You want some margin.

I think you can do two showers at once, but have the people start and stop the water use slowly enough to get the other person time to react if needed.

View attachment 47634

Got it...thanks. We only have one shower. I'm assuming the gray values are the gpm at that lift/psi?

 

[Jfharper]

Make sure that the pump does not take a couple minutes to do the last few psi before shutoff after using water

You mean when someone is using the water? Make sure it doesn't take a couple minutes for the last few psi? If it does, I assume I set the cutout to less...maybe 38.

 

[Reach4]

You mean when someone is using the water?

No. I mean when you have stopped using water. You want the pump to pumping enough water to keep cool enough. A 1/2 hp motor does not need a lot of flow, but it needs some.
If the pump is supplying water, it can run all day.

 

[Valveman]

That pump has a max pressure of 65 PSI. So from a lift of 50', it can only build 43 PSI. A 20/40 pressure switch is the best it will do, but it will work fine just filling the storage tank and not using a pressure switch.

 

[Jfharper]

No. I mean when you have stopped using water. You want the pump to pumping enough water to keep cool enough. A 1/2 hp motor does not need a lot of flow, but it needs some.
If the pump is supplying water, it can run all day.

I understand.

 

[Jfharper]

That pump has a max pressure of 65 PSI. So from a lift of 50', it can only build 43 PSI. A 20/40 pressure switch is the best it will do, but it will work fine just filling the storage tank and not using a pressure switch.

Thanks. Yeah, I will definitely be fixing the storage tank or replacing. I have to climb up there tomorrow morning and see whats what. It's about 25 feet on an extension ladder. Hopefully it is just the nipple screwed into the tank outlet, but I can't see clearly from the ground even using binoculars. Too hot outside to do it now...it's like 100 degrees F.

 

[Jfharper]

My well guy just mentioned maybe reducing the air pressure in the tanks so the well pump doesnt hammer. Might do that. I think they are at 38 last I check which was prolly a few years ago. Will see.

 

[Reach4]

My well guy just mentioned maybe reducing the air pressure in the tanks so the well pump doesnt hammer. Might do that. I think they are at 38 last I check which was prolly a few years ago. Will see.

Your air precharge (always check and set with water pressure zero) should usually be 2 psi below the cut-in pressure.

A bit high, and the water pressure will stutter before the pump can get the new water there. Way high, you will also get less drawdown before the pump needs to start again. Too low, and you will stretch the diaphragm more.