Well Foot Valve and Check Valve Problems
A well foot valve is a one-way valve with a strainer at the bottom of a jet pump's suction pipe, and its only job is to keep water in that pipe when the pump shuts off. When it leaks, water drains back down the well, so the pump loses prime, runs without delivering water, or cycles when no tap is open. Flotec's jet pump manual lists all three as foot valve faults.
Check valves do the same job elsewhere in the system. Submersible wells use check valves in the drop pipe instead of a foot valve, and those failures mean pulling the pump.
Foot valve vs check valve
They're both one-way valves. The difference is where they sit.
- Foot valve. At the bottom of the suction pipe in a dug or cased well, with a strainer on it. On a deep-well jet setup, it sits below the jet in the well.
- Check valve. Anywhere in a line where water must flow only one way. Flotec's shallow-well pump has one built in, and driven-point wells use a check valve near the well instead of a foot valve.
- Submersible check valve. Threaded into the drop pipe above the pump, down in the casing. Your pump's manual sets how many and where.
If you have a jet pump in the basement or a well house, you probably have a foot valve. If the pump is down the well and you only see a pipe and wire at the top, you have check valves.
Signs a foot valve or check valve is failing
Flotec's troubleshooting table matches symptoms to valve problems:
| What you see | Likely valve cause | Fix the manual gives |
|---|---|---|
| Pump runs but delivers no water | Leaking foot valve | Replace the foot valve |
| Pump runs but delivers no water | Check or foot valve stuck closed | Replace the valve |
| Pump runs but delivers no water | Foot valve or strainer buried in sand or mud | Raise it above the well bottom |
| Pump cycles too often | Foot valve leaks | Replace the foot valve |
| Air spurts from faucets | Leak on the suction side | Check the suction pipe and joints |
The classic sign is a pump that has to be reprimed every morning. Flotec says that with working foot and check valves and no suction leaks, a jet pump shouldn't need repriming in normal service.
How to test it
You don't need special tools for the first check.
Let the pump fill the tank and shut off.
Close the valve between the tank and the house, or make sure nobody uses water.
Watch the pressure gauge for an hour.
If the pressure falls with no water being used, water is going somewhere. On a jet pump, that's usually backflow through the foot valve or a suction-line leak. On a submersible, it's a check valve, a drop-pipe leak or a pitless adapter seal. Rule out a running toilet or a leaking outdoor spigot first.
Tools and parts
- New foot valve with strainer, the same pipe size as the suction line
- PVC or poly pipe, fittings and clamps as needed
- Pipe wrenches and thread sealant
- A bucket and water for repriming
Replacing a foot valve on a shallow well
On a shallow jet pump with an accessible well, this is a manageable owner job.
Power off
Shut off the pump breaker and drain pressure at a faucet.
Pull the suction pipe
Lift the pipe out of the well. Have a helper if it's long, because a wet pipe full of water is heavy.
Inspect
Look at the strainer and valve. Sand, a cracked body or a flapper that won't seat all mean replace.
Check the new valve
Flotec says to confirm the foot valve moves freely before installing it.
Set the depth
Flotec puts the foot valve and strainer 5 to 10 feet below the lowest level the water drops to while pumping, and 5 to 10 feet above the well bottom.
Seal every joint
Any air leak on the suction side stops the pump from priming.
Reprime
Fill the pump through the priming tee or plug. Flotec says water should arrive within 1 to 2 minutes of starting. If it doesn't, stop, refill and try again. Our how to prime a well pump page has the details.
Mistakes to avoid
- Setting the valve on the bottom. It pulls in sand and clogs.
- Ignoring suction lift. At sea level, Flotec limits total lift from the pumping water level to the pump at 20 feet, and about 1 foot less per 1,000 feet of elevation. A new foot valve won't fix a water level that's dropped too low for a shallow jet pump.
- Chasing the valve when it's a joint. A cracked fitting on the suction line gives the same lost-prime symptom.
- Repriming over and over. Each dry start is hard on the pump. Find the leak.
When it's a pro job
Call a well contractor when the check valve is down the well on a submersible, when the suction line runs to a deep-well jet, or when the pipe won't come out. Pulling a submersible pump is a two-person job with a lifting rig. While the pump is out, it's the time to replace the check valve too. See well pump replacement.
HomeGuide puts a check valve replacement at $150 to $200 and a foot valve at $150 to $400, both with labor.
FAQ
Where is the check valve on a well pump?
On a jet pump, it's often built into the pump or the suction line near the well. On a submersible, it's on the drop pipe just above the pump, plus sometimes one more near the pressure tank. Look for a short brass or plastic fitting with a flow arrow.
Should you put a check valve on a well pump?
Yes. Without a foot valve or check valve, the suction line loses its water every time the pump stops. Follow the pump manual for where it goes and how many.
How much does a check valve cost for a water pump?
HomeGuide lists $150 to $200 installed for a check valve and $150 to $400 for a foot valve. A submersible job costs more because the pump has to come up.
How do I unstick a well check valve?
Usually you don't. A valve stuck closed gets replaced, per Flotec's troubleshooting table. Sand and scale are the usual causes, so check the strainer and well bottom too.
Sources
- Flotec (Pentair)FP2521 Shallow Well Jet Pump/Tank System Owner's Manual (opens in a new tab)
- Minnesota Department of HealthWell Owner's Handbook: A Consumer's Guide to Water Wells in Minnesota (opens in a new tab)
- HomeGuideHow Much Does Well Pump Repair Cost? (opens in a new tab)