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Compressor parts and question

As I'm dong my service on the coach in preparation for an extended trip, all of a sudden the compressor starts cycling about every 5 minutes? Dang, just when I thought I was ready!
Thought I developed a leak somewhere, but then realized it was just the compressor cycling on and off. It seems to be an issue with the Auto Drain Solenoid.  Its the HWH part AP 6954 or RAP 91911.  I can't seem to find it anywhere. Seems HWH just wants to sell the whole filter unit. Picture below.

Question #1 - Does anyone have a source by chance ?
Question #2 - Could the whole water trap system be removed from the small compressor, and a whole new unit added externally?      I was looking at units with auto drain water trap, filter and dryer all combined.  Could the two wires to the auto drain solenoid be capped off, and the new external system take its place?

My thinking was the compressor would still kick on and off as needed for pressure or when the slide called for it to run, then the external system would accomplish the same thing as the HWH system, just without the electronic solenoid.  Thoughts ?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Compressor parts and question

Reply #1 –
HWH Filters and Bowls

See also

HWH Solenoid Valve Rebuild

It's likely either schmutz/seal hardening on the plunger/seat OR microcracks in the polycarbonate bowl itself, around the area of the fittings that the solenoid attaches to (thermal stress).

See resources above for the bowl with fitting (Grainger, IIRC, or FOT).  FOT should have the solenoid, and you can recondition/rebuild the old one to carry as a spare.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Compressor parts and question

Reply #2 –
I've got similar issues with my bowl, but one of the two wires is part of the problem. So I'll be watching for answers here.
2001 36' U320 Build 5901
2001 LX470

Re: Compressor parts and question

Reply #3 –
James, I dug into some of my archives and found these two wiring schematics. They may help you. Pending someone responding that will know much more about this than me, I believe that using an external water trap/filter system will accomplish the same task that the HWH setup does.
It looks like when the pressure switch cuts off, the drain solenoid then opens, thus auto draining the moisture.  I believe an external auto drain could do the same, therefore, bypassing the HWH setup.
Anxious to hear from those that may know?
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Compressor parts and question

Reply #4 –
FT parts dept should have the replacement bowl with solenoid.  Just replace it.  I did.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Compressor parts and Auto Drain other function.

Reply #5 –
The auto drain solenoid also serves to "vent" the compressor outlet after the compressor turns off. This allows for it to start "unloaded" reducing start up current draw and preventing a "stall" condition that could damage the motor.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Compressor parts and question

Reply #6 –
Quote from: MarkC –
1. It looks like when the pressure switch cuts off, the drain solenoid then opens, thus auto draining the moisture.
2.  I believe an external auto drain could do the same, therefore, bypassing the HWH setup.
3. Anxious to hear from those that may know?

1. correct
2. correct
3. done several with off the shelf trap that has a N/O drain with a 12VDC coil

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Compressor parts and question

Reply #8 –
Thanks Mike, That's what I was hoping to hear.  I know that a replacement bowl and solenoid are available from HWH, as over the years, I have had to replace them.
I am hoping to change to something external for more longevity and much cheaper, and more easily serviceable.
Do you think one of the non electric auto drains would work?
Thanks again for your assistance.
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Compressor parts and question

Reply #9 –
Quote from: MarkC –
Do you think one of the non electric auto drains would work?
Thanks again for your assistance.

I ran around with the drain hole plugged up at the bottom and no solenoid for a year and barely had any moisture in the bowl.  If there is moisture, its easy enough to unscrew the bowl and empty it.  The only value I can see in the bowl is to limit condensation.  But even with the plug in, there barely was any.
Joe Phebus and Jaime Trujillo
2002 U270 3410  Build: 5953 Motorcader # 18595
2100 W Solar, 600 AH Battleborn Batteries,  Victron Multi-Plus II 3000 Inverter, Cerbo GX, & MPPT Chargers
1992 Geo Tracker

Re: Compressor parts and question

Reply #10 –
Thanks Joe, I was even considering a desiccant dryer before the water trap to catch most of the moisture before it even hits the trap.
I think I'm going to do an external set up and see how it works.  I can do the whole setup cheaper than the cost of just the replacement solenoid, and I think it will give better performance.  Mounted on the wall in the storage bay will be much easier to access and service than having to get into the little compressor bay for sure.
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Compressor parts and question

Reply #11 –
Mark,

You will be far ahead and lot better system. I never had much luck with those float style drains when I worked, we used a electrical drain.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."
 

Re: Compressor parts and question

Reply #12 –
Quote from: MarkC –
Thanks Joe, I was even considering a desiccant dryer before the water trap to catch most of the moisture before it even hits the trap.
I think I'm going to do an external set up and see how it works.  I can do the whole setup cheaper than the cost of just the replacement solenoid, and I think it will give better performance.  Mounted on the wall in the storage bay will be much easier to access and service than having to get into the little compressor bay for sure.
I put my desiccant dryer after the drain valve with a check valve to keep the desiccant pressurized all the time. I liked the water separator electric drain valve system so much I copied on my bronco. Check valve just after allows the system hold pressure when relaxed.