Pump sizing?

Thanks in advance for all of the knowledge you guys share. I need to replace the check valve at my submersible pump sometime soon. I also have a check valve in the basement that keeps the pressure from draining back. We have lived here for over 11 years so the pump is older than that. I'm thinking if I must pull the pump to replace a check valve I should probably replace the pump at the same time.

According to a well report we got when we purchased the house it says the well is approx. 225 ft deep with approx. flow of 1 gallon per minute. I know this is not alot of flow but we can live with it if we don't water the lawn etc. It is 6" well casing and the level is approx. 50 ft from the surface. What size pump do I need. Thanks, Craig

With such a well, and such low production, a very small pump such as 1/2 HP [with the correct number of stages] would suffice. If your existing pump has worked correctly without problems except for a leaky check valve, simply replace it with a pump of the same specifications.

Also replace the down pipe with 1" black poly, 160 psi, if its not already, while you're in the hole.

You might install a franklin pumptec control to help in case of water shortage, along with a low pressure cut off pressure switch.

You have the luxury of knowing the problem, so take the time to shop and collect the parts at a good price for the eventual swap.

The other guys here will tell you to remove the check valve at the tank, but I have not seen any problems in my systems that have that.

There are two reasons I don't like a check valve up top is for health reasons and it can also mask problems in the well. Apparently from what you said, you had a leak down the well. Most people assume the check valve is bad, but this is almost never the case. It is usually a hole or crack in the droppipe which should be telling it's time to do some maintenance before the pump falls off completely.

bob...

Thanks for your replies. Do 1/2 hp pumps come with different # of stages? And what would the correct amount of them be for my application?

The reason I suspected a bad check valve is I started getting alot of rust in my whole house water filter and the water pressure is still strong. I thought if it was a cracked or broken line the pressure would be weak. I'm sure going to replace the droppipe anyway just to upgrade everything.

Also what health reasons are you eluding to with the second check valve?

Thanks

A submersible pump should be sized carefully for each well based on depth of well, gallons per minute and assumed average drawdown depth to water.

A 1,000 foot deep well may have a static water level of 50' from surface, and a pumping depth from surface at 5GPM of 300'.

If you have a pump that was working well, just replace that same one.

Depending on the number of stages a 1/2 hp pump will work from 10 feet to 500 feet and deeper, with various amounts of GPM.

It appears you do NOT know that you have a bad check valve on the pump -
rust is NOT a symptom. If you remove the surface check valve and cycle the pump, and upon shut-off you can hear water or detect water returning to the well, THEN and only then may you assume the pump check valve is bad or that you have a leak in the down pipe. I would move slow toward swapping the pump. You may be low on water in the well.

The pump you need is a 10 gallon per minute 1/2hp Submersible Pump. It will drop down to less than a gallon per minute at the 200 foot range so it won't over pump the well, but will deliver plenty of water at a higher elevation. It will also make plenty of pressure.

A Pumptec or Cycle Sensor wouldn't be a bad idea either with that low of a yield.

What can happen with a check valve up top is when that valve is closed, a vacuum can be created on the pipe between the up top valve and the pump. If you have a slight leak in your horizontal pipe, it could be sucking in contaminated water which would be delivered to the house next pump cycle.

bob...

Raucina said:

It appears you do NOT know that you have a bad check valve on the pump -
rust is NOT a symptom. If you remove the surface check valve and cycle the pump, and upon shut-off you can hear water or detect water returning to the well, THEN and only then may you assume the pump check valve is bad or that you have a leak in the down pipe. I would move slow toward swapping the pump. You may be low on water in the well.

Click to expand...

As I stated in the O post the water level is at 50' below the surface. We have not run out of water but we are getting lots of air coming out of the faucets. When the pump starts I can hear the rush of water coming into the tank. I have removed the well cap and cycled the pump and don't see or hear any leaks. It could be leaking in the down tube lower in the well or the check valve.


How would I check for leaks in the horizontal pipe?

Thanks

If you don't know where the leak may be, then you don't know that your not running out of water either.

Finding the leak in the horizontal pipe would be extremely difficult. But if you pull the pump and fix all leaks, turn off the main valve to the house and still have water going back, you can safely assume that pipe needs to be changed as well.

bob...