Well Pump Sizing??

[dieselscout80]

I have a 170' deep well that feeds my house, any yard watering and filling stock tanks. The house has three full bath rooms, kitchen and laundry. In an out building there is a 1/2 bath. In the future we'll be adding another bath room in the house either a 3/4 or 1/2 and I'd like at least a 1/2 bath in the garage at some point (if we ever build a barn a 1/2 bath would be great there too).

The current pump is a submerged pump with 2 wires IIRC, but I don't know the HP (we've only owned the place a year).

Possible future uses may include sprinkling some pasture grass in extreme conditions like this year since we are past 45 days with no rain.

I want to plan for a future well pump replacement what size pump should I look at getting as a replacement? Is just getting the biggest best? I think 1 HP is the largest size submersed well pump I've seen.

ps the previous owner used the well/pump to fill the one acre pond here when it was built about 3 or 4 years ago, so the current pump maybe living on borrowed time.

 

[mmurphy]

Is the the pump all the way to 170' depth of well? Some times well depth is not same as pumping depth. You need to have an idea of your pumping head, that is how far up your pump can push a column of water till it quits moving anymore water, or gpm desired.
2.31 feet of head = 1 psi.
A typical residential 3/4 water line with a meter flows about 5 gpm at 45 psi. (give or take a little)
It is important to know on pump selection, its pump curve to determine if that will do what you are asking it to do. HP is not a good determining factor.
My best advice is talking to a local well driller, to see what style of pump would be best for the USE you have in mind, and what water quality is there. Some water is hard on different styles and or materials of pump.
When you change that pump, put a air tube down with a pressure guage and valve stem much lika a car tire so you can find out with pressure guage a few times a year your pumping, and static level is doing.

 

[Egon]

You may want to start with the flow rate of the well and make sure that is not exceeded.:thumbsup:

Submersible pumps do come in larger HP sizes.

 

[dieselscout80]

You may want to start with the flow rate of the well and make sure that is not exceeded.:thumbsup:

Submersible pumps do come in larger HP sizes.

The guy we bought from said the well put out more than 150 gal per minute per the well driller. The town a few miles away wanted to buy water from the well.

I have know idea how far down the pump is. The line to the house is 1".

Where do you find the larger size pumps at?

 

[Jay4200]

I have a 170' deep well that feeds my house, any yard watering and filling stock tanks. The house has three full bath rooms, kitchen and laundry. In an out building there is a 1/2 bath. In the future we'll be adding another bath room in the house either a 3/4 or 1/2 and I'd like at least a 1/2 bath in the garage at some point (if we ever build a barn a 1/2 bath would be great there too).

The current pump is a submerged pump with 2 wires IIRC, but I don't know the HP (we've only owned the place a year).

Possible future uses may include sprinkling some pasture grass in extreme conditions like this year since we are past 45 days with no rain.

I want to plan for a future well pump replacement what size pump should I look at getting as a replacement? Is just getting the biggest best? I think 1 HP is the largest size submersed well pump I've seen.

ps the previous owner used the well/pump to fill the one acre pond here when it was built about 3 or 4 years ago, so the current pump maybe living on borrowed time.

The important metrics are (1) depth of water, NOT total well depth, and (2) desired GPM. If your well head is deep, then you need bigger pumps, however, if your well head is shallow (can you look down and see water?) then a too-big pump will cavitate and damage itself. The pump, regardless of depth, only pumps from the head level, not from where the pump itself sits. Every pump has a head depth vs. GPM curve. If your head is less than the lowest end of that curve, you can damage the pump. You can add pseudo-depth if required, however, by adding additional check valves in series (one at pump, one at pitless, one at tank - usually does it).

A typical residential pump runs about ~7-10 GPM or so. Pick a desired GPM, estimate your well head depth + line losses, then go to a plumbing supply house and they'll pick out the right pump for you. Gould is known as the best pump brand to get in this area.

Pumps usually last about 25 years. I wouldn't worry about filling a 1 acre pond, especially if the pump was running wide open the whole time. What kills a pump is start-stops, so short-cycling due to a bad pressure tank will significantly shorten lifetime.

JayC

 

[Egon]

Where do you find the larger size pumps at?

One source of many.


3" & 4" Submersible Well Pumps from Goulds & Myers

 

[dieselscout80]

The important metrics are (1) depth of water, NOT total well depth, and (2) desired GPM. If your well head is deep, then you need bigger pumps, however, if your well head is shallow (can you look down and see water?) then a too-big pump will cavitate and damage itself. The pump, regardless of depth, only pumps from the head level, not from where the pump itself sits. Every pump has a head depth vs. GPM curve. If your head is less than the lowest end of that curve, you can damage the pump. You can add pseudo-depth if required, however, by adding additional check valves in series (one at pump, one at pitless, one at tank - usually does it).

A typical residential pump runs about ~7-10 GPM or so. Pick a desired GPM, estimate your well head depth + line losses, then go to a plumbing supply house and they'll pick out the right pump for you. Gould is known as the best pump brand to get in this area.

Pumps usually last about 25 years. I wouldn't worry about filling a 1 acre pond, especially if the pump was running wide open the whole time. What kills a pump is start-stops, so short-cycling due to a bad pressure tank will significantly shorten lifetime.

JayC

Jay,

How do you find this out without pulling the pump?

If the pump has never been replaced its about 20 years old now.

 

[beenthere]

dieselscout80
If 20 years old, you will find out shortly (within a few years) when you pull the pump.

Just replaced mine, and the pump (1 hp) was down at 260'. Put the new pump (1.5 hp) down at 270'. The well is dug to 320'.

I let the pump/well guy put down the pump they handled, as then any problem it is up to them to fix. Are you planning to pull this yourself?

Look around the pump control box for depth information, or in some states there is a well report on file with the state (is in WI) when the well was first drilled (or pounded). Other than pulling, likely no other way to measure pump depth.

 

[dieselscout80]

dieselscout80
If 20 years old, you will find out shortly (within a few years) when you pull the pump.

Just replaced mine, and the pump (1 hp) was down at 260'. Put the new pump (1.5 hp) down at 270'. The well is dug to 320'.

I let the pump/well guy put down the pump they handled, as then any problem it is up to them to fix. Are you planning to pull this yourself?

Look around the pump control box for depth information, or in some states there is a well report on file with the state (is in WI) when the well was first drilled (or pounded). Other than pulling, likely no other way to measure pump depth.

Why did you switch to a smaller HP pump?

 

[beenthere]

Didn't....went up to 1.5 hp from 1 hp.