Magnet Trick for DuoTherm Cool Cat Solenoid (2006 DM T@b)

mdomb529

Summary:  Is it possible to use magnets to permanently lock the DuoTherm Cool Cat reversing valve in the A/C position in a DM T@b?

My DuoTherm Cool Cat heat pump starts up just fine and works great for heat.  Cooling is much less reliable - I read somewhere else in these forums about a trick to get the solenoid to switch to cooling mode: turn the thermostat to "cool," and if the DuoTherm kicks out heat instead of cool air, quickly switch the thermostat to "off" and then back to "cool."  Using this method (sometimes many times in a row), I was able to get cool air to come out, but not reliably enough, and I'm nervous about it switching back to heat mode in the middle of a hot summer night while we're asleep.

Because of COVID, replacement solenoids appear to be out of stock everywhere.  It may be back in stock some places now, but too late for my purposes because I have a trip coming up next week, and with the heat wave . . .

So, I found an Airstream owner who addressed the solenoid issue by using rare earth magnets to lock the reversing valve into the cooling position.  Here's a photo of the Airstream owner's solution.  However, I haven't found any reports of doing this with the Cool Cat in a T@b.  My questions are:

• Has anyone tried this magnet trick for their DM T@b Cool Cat?
• Does anyone see any reason why this wouldn't work for a T@b Cool Cat?
• Would I basically need to follow these instructions posted by @rfuss928 up to page 5 or 6 to get to the solenoid? 

Full-time A/C is perfectly acceptable to me, as a 20W electric heater is more than adequate for keeping my T@b warm even in February in Wisconsin. 

Thanks in advance!

rfuss928

The big project is removing the CC from the trailer.  Until it is completely out you can't remove the plastic cover and access the internal components.  The switching valve is not a conventional solenoid like the Airstream photo IIRC.  Not sure if the magnet trick could be adapted but if you have the skills and equipment the system could be hard plumbed to cool.  
I adapted a 8000 btu window unit after the third CC failure and removal.
Have fun!
Bob

mdomb529

Thanks, Bob.  I've been admiring your window A/C conversion for about a year now, but I've been dragging my feet, waiting for that magical weekend when I haven't already committed the time to some other "more important" project.  I've set aside tomorrow to see if I can get the A/C working using the magnet approach and to install my new MaxxFan.  I'll report back.

rfuss928

CoolCat parts diagram is attached.
Item #6 on page 4 is the switching valve .