I have two foaming brush tanks in my Coleman system that I need to manually change over with a simple twist of a ball valve. I was considering attaching a controlbyweb.com temperature relay to a solenoid that would automatically switch it over when the temperature reaches a certain temperature. The problem with that is that if the wash isn't busy and the temperature drops without the methanol formula running through the lines I would have problems. If I knew how to overcome this my idea would be easy to accomplish.
I made my own "switch" over system about 15 years ago when I switched my foam brushes from weeping water to methanol mix for the winter freeze protection.
I have two tanks, one with my regular foam brush mix, and one with my winter mix with methanol.
I have two Goulds pumps one for each. You could use any pump
flojet procon etc.
I have a normally open solenoid valve on the regular foam brush and a normally closed solenoid valve on the methanol mix line. I also have a normally closed solenoid on the methanol mix that ties directly into all my foam brushes after their respective solenoids for the air and the
soap mixture.
I control all the solenoids with my weep mizer output #2, which is basically a switch that closes when the temperature gets to 29 degrees.
At 29 degrees, the NO solenoid and the NC solenoids are energized. At the same time the second NC solenoid that is feed to the brushes after the air and
soap solenoids is tied to a simple plc that is timed for 1 minute. This lets the system purge the regular foam brush
soap with the methanol mix so no one has to be there to manually do it.
Once the temp rises above 29 degrees the two solenoids NO and NC are de-energized which technically turns the system back to using the regular foam brush.
This has saved my a lot of money by not having to first weep water as before, and also not having to run methanol mix all winter which is also very expensive.