Product review (5 stars): Solenoid fixed fill/drain problem, but...
...the rest of my TrueSteam is falling apart.  While removing the TrueSteam from the wall to fit the solenoid (a simple job to install the solenoid), the plastic nozzle that injects steam into the duct (remote install kit) crumbled. I've fixed it for this season with CPVC fittings.  They are likely not rated for steam, but neither is the plastic used for the TrueSteam!  I just replaced the tank and gasket a couple of months ago, and the new gasket is already leaking and the tank 'yellowing'.  I'm looking to replace the unit before next winter...possibly with a 220V GiantSteam.  They look like the Aprilaire units, but don't require return-air and outside-air sensors.