10-28-2026, 11:09 PM
Hmmmmm, had a few more thoughts tonite.
One, a well known guru, once worked on his HWH system, only to have it malfunction after a supposedly simple procedure. Turns out, if you leave the solenoid manually open the system doesn't work very well. It's worth verifying.
I was thinking what would I do if I were facing the situation you are. It seems you already have all the inputs and outputs identified and labeled. I would start at the beginning and while someone pressed the extend switch, I would measure the voltage at the connector for the pin retract solenoid, if I had voltage and the pins didn't retract, I would crack the fitting at the manifold to see if I had flow. It's slow but I would continue this process of manually checking for switch continuity, solenoid signal, and hydraulic flow through every step of the process. This would confirm that inputs and outputs were correctly connected and that solenoids were functioning. It would also pinpoint exactly what the HWH brain wasn't doing. AND it would set you up to provide and I/O logic to person programming either an industrial 12V Arduino, Rasberry Pi, or 12V PLC.
There has to be a niche market to replace all the older HWH stuff. They aren't supporting it, and thousands of motorhomes are using it.
By the way, glad you joined us. You are our kind of dude.
One, a well known guru, once worked on his HWH system, only to have it malfunction after a supposedly simple procedure. Turns out, if you leave the solenoid manually open the system doesn't work very well. It's worth verifying.
I was thinking what would I do if I were facing the situation you are. It seems you already have all the inputs and outputs identified and labeled. I would start at the beginning and while someone pressed the extend switch, I would measure the voltage at the connector for the pin retract solenoid, if I had voltage and the pins didn't retract, I would crack the fitting at the manifold to see if I had flow. It's slow but I would continue this process of manually checking for switch continuity, solenoid signal, and hydraulic flow through every step of the process. This would confirm that inputs and outputs were correctly connected and that solenoids were functioning. It would also pinpoint exactly what the HWH brain wasn't doing. AND it would set you up to provide and I/O logic to person programming either an industrial 12V Arduino, Rasberry Pi, or 12V PLC.
There has to be a niche market to replace all the older HWH stuff. They aren't supporting it, and thousands of motorhomes are using it.
By the way, glad you joined us. You are our kind of dude.
Richard and Rhonda Entrekin
95 Newell, 390 Ex caretaker
99 Newell, 512 Ex caretaker
07 Prevost Marathon, 1025
Maverick Hybrid Toad
Inverness, FL (when we're home
)

