Hi Jeff~

Before we talk about replacing the reversing valve…Let me say that since the introduction of digital controls such as the SMX…

Reversing valves sticking has become almost a non issue because the control activates/cycles the reversing valve often…This keeps it lubricated, as opposed to the older manual controls that only activated the valve when we wanted heat, which for some here in Fl was almost never…Or maybe once or twice a year…

I would first be sure that the reversing valve's solonoid coil (electro magnent) has power (full system voltage) in the heat mode, and that it indeed will hold a screwdriver placed into the hole in the center once the coil is removed…If that coil has no (or low) power, or won't hold a screwdriver then the problem is not a Stuck valve, but either with the SMX board not supplying power, or the coil itself has failed…

Replacing the valve…Though I can't quote time, not seeing what you have, or how far away the boat is from me, but I can say that 5-6 hours may not be unreasonable at the local rate….

It's not an easy job that 90% of the time, the unit does need to be on a bench (or on the dock box)…It's also fairly easy to overheat the new valve rendering it useless while soldering it in with a torch…That's not good when the new valve retails for $435 and you wouldn't know it was damaged until the unit is reinstalled & tested with refrigerant…

Though I have not overheated a valve in many years…I do warn my customers ahead of time of the risk, and that if it happens…It was/is up to them on what they want/ed to do, and on their nickle (valve & labor) if they decide to go with replacing the valve over a complete new unit…also that the new unit will be new, and have factory warranty…

I do sell the valves but it's under my $500 min order for discount…

Steve~