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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
How to prime the pump: this article describes how to prime a water pump to restore water pressure to a building by pouring water through a plugged opening in the well pump.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
An alternative water pump prime method that avoids any disassembly or the need for tools is at Prime the Pump by Garden Hose.
Also see Water Tank Types and before assuming that a water problem is due to the well itself, see Water pump and pressure tank repair diagnosis & cost an specific case which offers an example of diagnosis of loss of water pressure, loss of water, and analyzes the actual repair cost.
Our photo at page top shows the plug that would be removed to prime this Meyers pump by pouring water into the pump housing.
If your water pump is a two-line jet pump and if it's running but there is no water delivered to the building, the problem could be that the pump has lost its prime. This pump needs to send water down into the well (and through a special valve at the end of the water pickup-pipe in the well) in order to bring water back to the building.
See WATER PRESSURE LOSS DIAGNOSIS & REPAIR for help in determining why you have no water or no water pressure in a building. If the diagnosis determines that you need to re-prime the water pump, the instructions are provided in this article.
Where a two line jet pump is installed, you may have lost prime at the pump. The pump motor will run but no water is delivered.
If this happens it is possible to re-prime the pump with water from another source. Check valves installed at the proper location at the pump and perhaps elsewhere can help prevent loss of prime on this system. (Other problems that can give the same symptom include internal damage to the water pump, a well that has run dry, or a piping leak between the well and the building it serves.)
Turn off the water pump if it is running "dry": If your jet pump (or other above-ground well water pump) loses prime and cannot draw water from the well, don't let it keep running as you may burn up the pump motor or damage the pump internal parts. The pump won't be damaged if it runs dry for a minute or a few minutes, but leaving it running for half an hour with no water could be another story.
Before following this procedure to directly prime a dry water pump that has lost its prime, you might want to try the simple Prime the Pump by Garden Hose that we describe above.
Our photo (left) shows the two line F&W (Flint and Walling) two line jet pump in our lab. That big brass plug in the center of the top of the pump body (center of the photo) closes the opening that is used to prime the pump if it should be dry. Don't take out this plug before reading the instructions below.
If your water pump is a submersible unit the pump is located down in the well itself. In this case if you have not got water pressure, the problem may be with the pump or the well itself, but it's not a loss of prime - submersible water pumps are self-priming.
If your water pump is a one-line jet pump, it is sucking water from a shallow well; you probably don't need to do so, but the instructions below show how to prime the well pump and they should work equally well for either a one-line jet pump or a two line jet pump.
If your water pump keeps losing prime, a shallow well jet pump well line could have a bad foot valve (in the well) and so be losing prime. A leak in the well line can also lead to loss of prime. If priming the well water pump using one of our methods shown below seems to fix the problem but soon the well pump loses prime again, your plumber will want to check for a bad foot valve in the well or a leak in the well piping between the well and the building. See WATER PRESSURE LOSS DIAGNOSIS & REPAIR.
Frequently Asked Questions (FAQs) about how to prime a well pump using the pump priming plug opening
Question: Wayne CSW50 2-line jet pump, lost water pressure.
I'm absolutely confounded by my system. While we were away on vacation, the folks taking care of our animals called to tell us there was no water in the house. This is only to say I have no idea what's happened during the last 7 days to get to the point of having no water. When I got to looking, the pressure switch did not appear to be working because the pump would run when I bypassed the switch applied current directly to the pump.
So I replaced the pressure switch, and the pump seemed to work fine. However, priming has been a problem. This pump is less than a year old, and I didn't have trouble priming it the first time (using the 2nd, or plug method) when I replaced the old one. But this time - no dice. I do have a shutoff between the pump and pressure tank. When I close the valve, prime the pump, and run, enough pressure builds to trip the pressure switch and shut the pump off. But as soon as I open the valve to fill the house (or if I prime with the valve to the house open), it won't prime. I also filled the pressure tank with some air and noticed a slow leak. This system predates me, and I don't think it's a bladder type.
My pump is a two line jet pump, Wayne CSW50. There are no markings on the pressure tank, so not much there. One odd thing I did notice when I added air to the system was that I got air coming up from around the area where the lines go through the surface into the well. I didn't expect to see air escaping there. I didn't think much of it since I could get the pump to pressure up when shut off from the house - but in the interest of full disclosure in case it sparks a thought.
Mr. McCurdy: you might get somewhere in diagnosing this well water loss problem by starting with the diagnostics at the article WATER PRESSURE PROBLEM DIAGNOSIS TABLE - I'd start there rather than looking at pump priming (the article series here).
However, your clue that you got air coming up through the ground around the well piping near the pipe entry into the well suggests that there is one or there may be two issues:
1. a leak in well piping near the well - dig there and investigate the pipe condition, or look for a leak at the pitless adapter
2. an air leak into the well piping or low water in the well allowing air into the system
Question: Goulds 2-line deep well jet pump, worried about warm pump motor during priming
I just finished installing a Goulds 2 line deep well pump. I am currently priming the system, but I'm concerned about the electric motor housing getting warm. Is this a normal occurrence? I'm worried that the motor will burn out and my pump will be no more than a paperweight. Also, after installing a new pump, how many times should the pump be manually filled with water? How will I know when full priming has been achieved? - Brian Scholtes 9/9/11
Brian, it's normal for the pump motor to get warm but not red hot - usually you can find temperature numbers on the data tag. Don't run the pump dry however as you may damage the impeller. Usually I can get the pump working with just 1-3 fill-ups of prime, but it could be more depending on the depth of your well piping.
Question: leaky foot valve, pump and pressure tank are preventing loss of prime
I just used this method last night and we were lucky it worked. An electrician had installed a new circuit breaker panel and power was off for several hours. They tried to re-prime it but no luck. We thought we were looking at a $3K bill to open the well and finally make the switch to an in-well pump.
One thing I did not see (or missed) -- I closed the valve between the pump and the tank, so all the water I poured in went into the well line. I did have to be nimble -- fill it fast, quickly screw the gauge back, and flip the switch.
When the pump luckily started pumping, I opened the valve [to the tank] slowly. Our well guy suspects that we do have a leaky check valve, but as long as we don't lose power, we seem to be OK for a while. - Bob Stewart 8/25/2012
Reply: effects of slow well pipe or foot valve leaks on losing prime - relation to power outages
Thanks for the helpful field report, Bob.
Indeed a leaky check valve or foot valve means that whenever the pump stops water drains from the above-ground 2-line jet pump back into the well. The reason you don't lose prime immediately is that water stored in the pressure tank is feeding backwards into the well as pressure drops due to the leak. As pressure drops to the cut-in, the pump cycles on, repressurizing the water pressure tank and piping, and so prime is preserved for now.
This is the classic situation in which people observe
Questions & answers or comments about how to prime a well pump - priming through the pump body itself.
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