How to Install a Pool Check Valve

What You'll Need
Replacement check valves
Strap wrench
O-ring lubricant

A pool check valve keeps pool water from back-flushing into the filter from the solar heating panels whenever the pool pump is not turned on. A solar heating system for a swimming pool uses pipes located beyond the filter to move the water to the solar panels. The sun heats the water through the panels, then the water is carried back into the pool. Pool plumbing systems usually run quietly. Any type of gurgling sound that may be coming from the filter may be an indication that the check valve is leaking and needs to be repaired or replaced. 

Step One – Examining the Valves

Before you begin any work on the pool plumbing system, make sure that the pool pump is turned off. Carefully examine the two check valves. Look to see the direction of the flow from each of the check valves. The exterior covering on the valve should have an arrow indicating the correct flow direction. 

Step Two – Loosening the Fittings

Loosen all of the fittings on one end of one of the check valves with the strap wrench. Continue with the other end of the valve. It is important to replace only one check valve at a time so that you do not confuse the direction of the water flow. When all of the fittings to the first check valve that you are replacing have been loosened, remove the valve from the unit. 

Step Four – Lubricating the O-Ring

Be sure that the lubricant you are using is one made specifically for pools and that it does not contain any oil that might get into the pool water. Carefully apply the lubricant to the O-ring for the new valve. Position the new check valve. Tighten all of the fittings on one end and then on the other.

Step Five – Finishing the Lubrication

Loosen the fittings to the other check valve. Remove the second valve from the unit. Carefully apply the lubricant to the second O-ring. Position the second check valve. Tighten all of the fittings to the valve. 

Step Six – Testing the New Check Valves

Turn the pool pump back on. The water should be flowing properly both to the solar panels and from them back into the pool. Turn off the pool pump again in order to test the valves. You should not be able to hear any gurgling sounds coming from the filter. The entire pool plumbing system should be working silently.

Step Seven – Preventing Check Valve Problems

Be sure to check that the lint basket of your filter system is empty on a daily basis in order to prevent the check valve from backing up. If the basket is full, it will prevent the water from flowing freely into the check valve. Remove the basket and empty the contents. Ensure that you re-apply your lubricant on the O-rings every six months so that the check valve system will not be damaged by any corrosion.