Solenoid Valve FAQs

Hayward Solenoid Valve FAQ’s

Is the Hayward solenoid valve normally open or normally closed?
It is normally closed. When there is no power to the valve, it is in the closed position.

I want to cycle it all the time, what is the duty cycle of the valve?
The valve has a 100% duty cycle and is rated for continuous duty. It can be in the open position, with power applied, all the time without problems.

Can I use the valve with slurry type fluids?
No. Particulate matter can prevent the piston from completely closing the valve - causing leakage.

The coil on the valve get real hot, what “burn out” protection is there?
There is none and none is needed. The outside temperature of the coil can reach 180F in normal operation and will cause no damage to the valve.

At ambient temperature the chemical resistance chart shows my process media as OK with the valve and seal materials yet I’m still getting seal leaks. What’s wrong?
Fluid inside the valve can reach temperatures above ambient because of the operating temperature of the coil. The hot coil heats the process media which can raise its temperature considerably. Remember, the fluids that may not affect the valve seals at ambient temperature can cause problems at higher temperatures.

How fast does the valve open and close?
The valve opens and closes almost instantaneously.

The catalog says that the flow velocity through the solenoid valve should not be greater than 5 feet per second. Why?
As the flow velocity increases so does the potential for generating damaging shock pressures as the valve opens and closes. At flow velocities above 5 feet per second, this shock pressure can be great enough to damage the valve, especially the diaphragm seals.

My valve sometimes “sticks” and won’t close, what’s wrong?
If the inlet pressure is greater than 25 PSI, and the pressure differential (the difference between the inlet and outlet pressures) must be GREATER than 25 PSI of the valve to open and close smoothly. You can test it by operating the valve without pressure or flow going through it to verify that that is the cause.

When I go to close the valve it makes a “chattering” sound. Why?
Same answer as the last question.

The catalog says that the valve is rated at 150 PSI, yet the valve specs say that the inlet pressure can’t be above 120 PSI. Why?
The valve itself can withstand 150 PSI without damage, but the coil and spring that open and close the valve won't work above 120 PSI.