I have an OM tech Rudia RDC6442G-B that has worked great with the wind pin with about 800 hours of burn time and my WIND pin gives really erratic voltages when it should be on.
Idle - 20V (Meter only, will not open the 24v solenoid)
On - 6 V (this is across the solenoid, not strong enough to open the valve)
My work around was to wire it to the CN1 pin4 (Status) so that its on when the laser is on.
Just looking for other’s experences.
The solenoid may require slightly more current to activate than the controller transistor can sink, so it’s been operating on the ragged edge of not working all along.
The 6442 manual says the output is good for 500 mA, which may be marginal for your solenoid.
I used a solid-state relay to buffer the controller, so its precious transistor sees only a few milliamps of current:
If the transistor is still kinda-sorta working, then unloading it with a solid-state relay may put a happy Wind in your sails.
This seems more common that I thought… I’ve see this occur multiple times. The people that have been into them claim they are not really complicated. Most of the packages are smd, from what I remember.
I have see photos and such of a replacement of the mosfet. Some claim it’s a transistor some a mosfet, but there is some information on it on the RDWorkslab website.
You have to register to access the site… I did mostly reading and am no longer a member… I assume I didn’t post enough, but was never told…
There is a number of them over there…
https://rdworkslab.com/viewtopic.php?t=5684
Good luck
Can you recommend a relay so I don’t burn out the next one?
Would prefer one with 2-3 channels.
I have run this for both Status and Wind since I got the air assist up…
Both solenoids have some type of reverse protection that is only a small signal diode. I think I have a bunch of 1n914s around.
Solid state relays come in DC and AC variants, depending on their output specifications. You must use the proper type, because they are not interchangeable.
Both types have low-voltage DC control inputs. You wire the + terminal to the power supply + terminal (5 V will work, but 12 or 24 V are preferred) and the - terminal to the controller’s output. The controller pulls the terminal low when it is active to apply the full power supply voltage across the relay input, whereupon the relay output goes active.
For DC solenoids / valves:
Serving suggestion:
For line-voltage AC fans / lights:
https://www.amazon.com/uxcell-ASH-25DA-3-32VDC-480VAC-Authorized/dp/B01LXLEBHQ/
Serving suggestion:
Uxcell is something like an organized group of manufacturers with at least nominally better QC than the usual low-end Amazon sellers. You’ll also see Fotek branded relays, but from what I’ve read, essentially all of them are counterfeit built with crap components.
You use single relays so a failure doesn’t make you feel bad about junking the good ones, too. 
The simple fact is the Ruida is broken.
Using an ssr, may or may not work as the actual hardware signalling it is broken.
That’s unclear. The poor little transistor inside the controller may not be conducting quite enough current to handle the abuse from the solenoid, but may still be able to activate a piddly solid state relay.
It’s a fifteen buck test before dropping four Benjamins on a new controller and, even if it doesn’t solve the problem, it’ll come in handy with the new controller.
What’s not to like?
That’s part of the definition of it’s broken.
Not saying it won’t work… just you’re dealing with a know electrically failing/failed device.
If it will work or not is a crap shoot. Probably won’t hurt anything, but you still can’t depend on it…
If it were me, I’d crack the case and fix it … 
Do you have any ideas about which Component needs replaced?
I would go back to the RDWorks forum site I mentioned and join them. Then you can peruse their documentation on this issue. There is little that comes up from a search engine on the query that I used.
You can also post a question there about the issue. I would be someone already has your answer along with the right component.
This photo came from that site. I believe the top left four components are branded P7 and is common on many types of transistors, bjt and mosfets. The ones on the right appear to be optical isolators… The number of these is P785, that does come back to this type of device.
My guess would be one of the four in the upper left…
I have no board, have not been inside one of these… so take my opinion with a grain of salt…
Good luck
