How to Size Reservoirs

[wrightwash]

Hello All,

I'm remodeling a wash and working on getting some new tanks ordered for rinse, soap, etc. to replace an existing rotten fiberglass tank.

I'm running 5 CAT 430 Pumps, which are 5 GPM. On the CAT inlet design pamphlet they specify that the supply reservoir should be 6-10 times the GPM of the pump.
So for my application I would need a 30-50 Gallon Reservoir for Rinse. What would I need for Soap and Wax? From looking at other units the Soap and Wax tanks are considerably smaller, usually around 1/3 the size of the rinse tank. Is there a rule of thumb for sizing this or could someone give me their sizes as a reference?

 

[MEP001]

Are you planning to run the bays at 5 GPM? Typically you run them at slower than maximum RPM and 3 GPM at the bay.

My tank is 1' wide by 2 1/2' tall and deep, and is pretty typical in size for a car wash. The soap and wax can be much smaller since only a small fraction of the liquid drawn by the pump is the chemical. My tank is three tanks the same size with only about 8" in the soap and wax tanks.

 

[mac]

If you have good water pressure something around 15 gallons for rinse will do. Soap and wax can be much smaller as when the system calls for either the pump still gets its main water from the rinse tank and just a little of the chemical is sucked into the pump.