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!

Soap Back Flowing Into Rinse Tank Laserwash 4000

  • Thread starter Thread starter loewem
  • Start date Start date
L

loewem

Guest
Having a problem with pre-soak back flowing into the rinse tank. I starts at the end of the 1st pre-soak pass. Soap is back flowing steadily from the smaller pick up up tube in the rinse tank. This continues through the end of the second pre-soak pass. When the high pressure rinse kicks on it takes about 8 to 10 seconds before high pressure begins and it is only producing at about 750 PSI.

What has been done so far:

- replaced check valve prior to where low pressure T's into the high pressure rinse hose.
- checked all danfoss valves at injectors.
- removed the hoses from the high pressure chemical injectors, plugged the hoses and ran pre-soaks manually.
- rebuilt the lexair valve for the high pressure rinse.

PDQ suggested removing the overhead low pressure lines to see if chemical back flows from any one line. I don't see how it can be on the low pressure side.

Thanks in advance for any help.

View attachment 1018
https://youtu.be/peB3Yrgy-20
 
The low pressure check valves on the wall above your pump stand that T into the big stainless manifold before it goes into your foaming/scrubby pad one of those 1/2 or 3/4 check valves may be may be bad. PDQ is saying take each hose coming off the danfoss hose at the tree/overhead manifold and leave one attached like soap 1 and press 100 enter 10 enter and see if soap is coming through the other valves then you know you have a bad Danfoss or check valve. (I always test danfosses and take them completely off the injector to get a sure test also.) good luck
 
Thanks for the help. Rebuilding the hp unloader fixed the soap on the rinse tank problem. I had a problem with a pop off valve releasing diring the hp cycle. Traced it back to my clear coat danfoss valve. It is happening again and thinking it might not be a danfoss valve. Could it be one of the check valves?
 
You have a cracked PVC fitting inside your HP rinse tank. Or the 1 1/2 PVC check valve inside the HP rinse tank is bad, or the union is loose.
 
Back
Top