Pump Inlet Hose Size for Soap and Wax

[wrightwash]

I'm to the point in our car wash rebuild that it's time to order plumbing materials and valves.

I'm running Cat 430 pumps, which have a 1/2" inlet. They are gravity fed from a pump that's roughly 20" above the pumps. I was considering going with a 3/4" coupler out of the tank to a 3/4" BV and Y-Strainer, Tee in for soap and wax then 3/4" hose to a 3/4" to 1/2" reducer at the inlet of the pump.

While reading on the forums I noticed some comments that 3/4" hose causes suction issues for the soap and wax mixture. Would it be best to run 1/2" from the tank to the inlet?

Also, for my soap and wax valves, I have a 1" coupler in the tank from which I was going to create a header running to 1/4" KIP Solenoid valves, then 1/4" poly tube to the tee's on the pressure line. Is 1/4" valves the normal for this? Also do I need a metered valve?

Thanks in advance! My background is industrial automation, I'm slowly mending that into the car wash world. We're two months into a 5 bay SS car wash remodel.

 

[Randy]

We got rid of the problematic tanks, flow valves years ago and went with a direct feed water into the pumps, simple to do if you’re rebuilding everything. 2 - ½” solenoid valves for hot and cold water, a Generant pressure regulator to lower the incoming water pressure, and a DEMA 203C injector for the chemical. We have a ½” PVC manifold that runs behind the pumps to supply chemical to the injector, the chemical supply tank is about 5 feet high. We use 2 - 1/8” Kip valves to supply chemical to the DEMA injector.

 

[MEP001]

I run 1/2" hose to the pumps - whether I use push-lock hose or polybraid, I still use push-lock type hose barb fittings that are almost 1/2" inside so there's no restriction. If you're running hot water for soap and wax but cold on rinse, you need a check valve on the hot water line. It's a good idea to have one even if it's all cold from the same tank to prevent any backflow into the tank. I usually use 1/4" OD tubing to the pumps for soap and wax lines unless there's a long run across a bunch of pump stands, in which case I use 3/8" ID. The solenoids will all have the same orifice which becomes an equal limiter to flow, so you shouldn't need individual adjustments.

 

[wrightwash]

I run 1/2" hose to the pumps - whether I use push-lock hose or polybraid, I still use push-lock type hose barb fittings that are almost 1/2" inside so there's no restriction. If you're running hot water for soap and wax but cold on rinse, you need a check valve on the hot water line. It's a good idea to have one even if it's all cold from the same tank to prevent any backflow into the tank. I usually use 1/4" OD tubing to the pumps for soap and wax lines unless there's a long run across a bunch of pump stands, in which case I use 3/8" ID. The solenoids will all have the same orifice which becomes an equal limiter to flow, so you shouldn't need individual adjustments.

Thank you! So you add a check on the feed line before the wax and soap tee?

 

[wrightwash]

We got rid of the problematic tanks, flow valves years ago and went with a direct feed water into the pumps, simple to do if you’re rebuilding everything. 2 - ½” solenoid valves for hot and cold water, a Generant pressure regulator to lower the incoming water pressure, and a DEMA 203C injector for the chemical. We have a ½” PVC manifold that runs behind the pumps to supply chemical to the injector, the chemical supply tank is about 5 feet high. We use 2 - 1/8” Kip valves to supply chemical to the DEMA injector.

Good to know! Thank you.

 

[MEP001]

Thank you! So you add a check on the check on the feed line before the wax and soap tee?

I usually put it as close to the pump as possible so I can use polybraid hose on push-lock fittings without hose clamps.