What's new
Car Wash Forum

This is a sample guest message. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

HP check valve

BayWatch

Jedi apprentice
Each bay of my self serve has a check valve for the high pressure water line on the manifold above each bay. The presoak, tire cleaner, and rainX also attach to this manifold and they also each have a check valve. My question is: Is it ok to have another check valve on the outgoing line from the HP pump in the mechanical room? I have an issue with the weep water back flowing thru the pump and then overflowing the water storage tank. The check valve would be between the pump and weep inlet. I thought about running the weep to the manifold on each bay but then there would be a length of HP hose from the pump to the manifold without water flowing thru it and thought it would freeze.
 
You may have another issue that's causing your problem. There's usually a low-pressure check valve on each line between the pump and the tank. Adding another check valve may compound your problems rather than solve yours.
 
There's usually a low-pressure check valve on each line between the pump and the tank.

+1
but I suppose that if you dont have city pressure cold water rinse tee'd in then you wouldnt necessarily need that CV. If that is the case then no, the extra CV you describe should be fine.

I do agree with mep though about masking other problems. For example, if [weep] water is flowing backwards thru your pump then the pump valves might be faulty.
 
Last edited:
Not sure I follow, but I think if I describe my setup a little more, it may help the readers. My setup is water tank, pump, then on pump outlet is a tee, then HP hose to bay. The tee is the inlet for the weep. Most of the pumps will back flow a small amount back into the water tank. The pumps run fine, no pulsation. I was thinking about putting the HP check valve between the pump and tee. I have also thought about putting a LP check valve on the line between the tank and pump but am worried about not having enough water flow to the pump and starving the pump.
 
You could install a pvc Ball check valve made by hayward, from the tank to the pump. These will not reduce water flow/volume and will last as long as pvc does. This way your tank will never overflow due to back flow through pump/weep.
 
My system and hundreds like it use 4 HP check valves.

One keeps HP from flowing back into the weep. One to keep the weep from flowing back to the pump and overflowing the rinse tank. They also keep LP functions from flowing back to the pump and weep system.

The third CV over the bay keeps the HP from blowing up the LP plumbing. The fourth CV keeps the HP from flowing into the SFR supply.
 
BayWatch said:
Not sure I follow, but I think if I describe my setup a little more, it may help the readers. My setup is water tank, pump, then on pump outlet is a tee, then HP hose to bay. The tee is the inlet for the weep. Most of the pumps will back flow a small amount back into the water tank.
To that extent, that's how most pumps are set up. If you run hot water on all functions, you may not have a low-pressure check valve between the pump and the tank because there really isn't a need for one. If you have a solenoid that supplies cold water at city pressure for the rinse cycle, there must be a check valve on the hot water line or the tank will always overflow if one customer uses rinse. If you have such a setup, those check valves are bad. It's not at all uncommon for there to be one, so as long as it's rated for the flow the pump needs it won't cause a problematic restriction.
 
Back
Top