Skip to main content ↑ ↓
Topic: HWH Sleep Mode Question (Read 812 times) previous topic - next topic

HWH Sleep Mode Question

In searching the archives I've come up with posts that provide different answers, and I read through the HWH documentation and didn't find an answer.  HWH tech support takes several days to respond.

Coach:  1998 U-320 36' non slide
HWH System:  Series 600

When the HWH Series 600 system goes into sleep mode, what PSI has to be in the main air tanks before the 12 volt Aux compressor will engage to relevel the coach?

On our setup the Aux compressor does not fill the main air tanks on the coach.

Thank you,
Chris

Re: HWH Sleep Mode Question

Reply #1 –
Quote from: Numbers –
When the HWH Series 600 system goes into sleep mode, what PSI has to be in the main air tanks before the 12 volt Aux compressor will engage to relevel the coach?
The simple answer is this: when system pressure falls to approximately 85 psi.

Where did I find this info?  There are two excellent HWH manuals available online for your enlightenment.  Links provided below. 

In the HWH Systems Textbook, on page M140.019A (System Pressure Switches) you will read:

"Pressure switches used to monitor system air pressure are usually set at 85 psi, although some manifolds have a pressure switch set at 100 psi."

I believe all Foretravel coaches use the 85 psi pressure switch, which is mounted on the rear 6-pack manifold.

http://www.hwhcorp.com/ml20635.pdf

http://www.hwhcorp.com/ml13985.pdf
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: HWH Sleep Mode Question

Reply #2 –
Hmmm.... Wonder if this rear pressure switch is what is preventing mine from pumping up the system to achieve level when main tanks are low on air???
I do have a contamination issue with desiccant from old compressor & dryer. (May have to bite the bullet and replace the wet tank)
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: HWH Sleep Mode Question

Reply #3 –
Easy to check.  Test the continuity on the two contacts on the pressure sender.  Check with air system topped off, and with system depleted.  Should be a change in continuity between tests.  I can't remember if sender is normally open (NO) or normally closed (NC).
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"