HWH Control Box meltdown

[pyrosecur]

Hi all! I have a Tiffin Allegro 2004 32BA equiped with HWH 325 hydraulic system. On a recent trip one of my red lights was on to indicate a partially extended jack. This occurs often on hot days, the jack is only extended about a 1/4". I was told by the dealer to just activate the STORE button and not to worry about it overheating as it would cycle off automaticaly after 2 minutes. Well this advise worked for the past 19 years. However on my last trip I stopped to gas up and after the vehicle sitting still for arond 15 minutes without airflow over the control box it started on fire from the inside and completley melted the circuit board and housing. The fire spread to the exterieur but luckily was able to extinguish it before any major damage to the motorhome.
Obviously my jacks no longer operate. I have removed the control box and there appears to be no damage to the wiring connections to the harnesses. I would like to order a new Control box unit from HWH but I would like to know what type of tests I should run before ordering it at 800+
I have run power directly to the solenoids and can here them click so i presume they were not damaged. Bit I would like to know how I can verify the pump motor is operating.
Your insights ans suggestions would be greatly appreciated.
Thank You Gerry

[enblethen]

Thanks for the update! Safe travels!

[pyrosecur]

I have changed the control box along with one hose which had burnt in the fire. There was also a 3 amp fuse in the control panel which had burnt out which I had to replace. Everything is working now 🙂

[pyrosecur]

I will try to short the moter too see if it still works.... Thanks for the info

[pyrosecur]

As you can see from the forst two pictures the damage is quite extensive, I don't think theay can rebuild it.

https://photos.google.com/photo/AF1QipMarNjMLdzInZQ436vBnmrVcTNYiVp6gUhJR-2g

https://photos.google.com/photo/AF1QipOf5hShDef8b2ZMPxbEkA5l1beGEudIHyf2NeOP

This is the back of the unit:

https://photos.google.com/photo/AF1QipNtAwZ-PdNBzmsSKk5R3InnXZwF9T4F_8g3MzEK

[dougrainer]

https://www.ebay.com/itm/225565560427?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mksc...


This is what it looks like. Doug

[dougrainer]

To verify pump operating is simple. By the plexiglas and the motor housing is a large 12 volt solenoid. 2 large nuts. One is the 12 volt battery cable supply from the battery. The other goes to the motor. You will see the wire from the motor to that solenoid. Just jump the 2 large bolts with an insulated large screwdriver. The motor will run if OK. Doug

[dougrainer]

OK lets go back to what you were told 19 years ago.
1. IF a jack(300 system) will NOT completely retract and its red light comes ON, you either manually lever it completely up or disconnect the 2 wire down switch at the top of the jack
2. IF it then retracts after you hit store and the red light goes out, you are good to go.
3. The CORRECT procedure for HWH 300 series jacks is to ALWAYS PUSH THE STORE BUTTON EVERY TIME YOU START THE CHASSIS ENGINE TO TRAVEL. This IS explained in the 300 series operators manual, NOT well explained, but it is stated to do this. This is because the TYPE system and down switches on the 300 series, Road heat and exhaust heat if close to a Hydraulic line will cause fluid expansion in the line and will partially extend the jack on that Hydraulic line. JUST ENOUGH TO EXTEND ABOUT 1/4 INCH AND CAUSE THE DOWN LIGHT FOR THAT JACK TO COME ON. By pushing store everytime you start the engine you put the system into hibernation(standby) and IF the heat expansion causes a jack to partial extend, the system will automatically engage store and the jack will retract and this happens BEFORE you get a red down light and alarm.
4. Now, IF you travel more than 30 minutes with a Red Down Light AND have the system in store and the down light stays ON, you will burn out the solenoid for THAT Jack. This is also true of the 600 series HWH jacks.
5. There is NO NEED for any type cooling of the system computer. ALL components are low dc amperage(no more than 15 amp in any circuit) EXCEPT the amperage needed for operating the Pump 12 volt motor. ALL circuits are fuse protected in your system UNLESS someone installed a larger ATC mini fuse in one of the fuses over the years.
6. IF NOT needed for a few months, I would send the defective control box to HWH for rebuild. This is cheaper but you have to wait for them to rebuild it.
7. Is your control box the one with the clear Plexiglas cover or the silver rectangular box? Your AP number IS the clear Plexiglas control box Doug

[pyrosecur]

RAP30045
Control unit (not panel)

[enblethen]

Do you have HWH ap number? Price sounds high!
Ebay