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!

Hose size, attic.

copperglobe

Active member
What size hoses for HP are now being run from the pumps out to the manifolds above the bays; across the attics? 3/8 or 1/4 inch?
 
I use 3/8". I once tried 1/4" on the bay right next to the eq. room and the difference was noticeable. I changed it back to 3/8 shortly thereafter.
 
I have 3/8 in trough and 1/4 from the end of the boom to gun. I had too much pressure loss with the long 1/4" runs.
 
You have to increase the pressure somewhat to compensate for the line diameter decrease and the resultant loss of pressure. The easiest way to do that accurately is to build a tee with a pressure gauge on it and put it on the nozzle end. Then, when you get the desired nozzle pressure, mark the pump discharge pressure on the pressure gauge with a sharpie so you know what yu need to be pumping. You can also use this technique to ensure pressure consistency from bay to bay. It takes a few extra hundred PSI at the pump with 1/4 hose but my setup with cat 5cp2120s and 3HP motors seems to work fine. I do use a lower end of the pressure sprayer at a 2506 nozzle and 1000 psi at the tip. The changeover time seems noticeably better when you're waiting for it, but in reality it's probably somewhere between 5-20 seconds, depending on the distance of the bay from the equipment room.
 
3/8 in the trough, 1/4 in the bay.
I also tried 1/4 in the trough for 1 bay many years ago, but since I run 1225-1250 psi in my bays I had to really crank up the pressure at the pump to get the desired bay pressure. (around 2000 iirc.) I didnt like that, so I stuck with the 3/8. Slightly slower changeover is the only downside that I can think of as well.
 
Over here in NC we have been runnin 5/16 hi pressure hose for many years. Its a good hose and has lasted forever. Uses a reusable fitting. We(I) at least never knew we needed to change the size of the hose. I dont know how that affects it. For low pressure we have always used 1/4. I switched to 3/8 one time and didnt like it. changed back to 1/4
 
Last edited:
Back
Top