Similar to the Intellitec ECC, the Waiter Legacy system uses two sliding resistors for adjusting the temperature and two 7 position switches to select the system mode. As the your system gets older with a lot of use and being exposed to dust, dirt, humidity, etc, the temperature slides and mode switches may start to become more difficult to move and may not be as responsive as when they were new.
In almost every case, simply cleaning and lubrication of these components restores their original functionality. We discourage the use of common spray cleaners like WD40, CRC, etc for this job and recommend ONLY a product that’s designed specifically for use on electronic fader controls, DeoxIT Fader F5S-H6, can be purchase on Amazon. Depending on how much you use your motorhome, cleaning the temperature and mode controls once or twice a year should be adequate.
Move all four controls to the very bottom of their travel, insert the spray hose into the control as far as it will go (about an inch), give it about a 1/2 second blast of cleaner. Rapidly move the control up and down a dozen times.
