I put a Nordyne board in my Goodman about five years ago, because the timed defrost drove me nuts. 90% of the time it defrosted when it didn't need it, and in humid/foggy conditions it turned into a giant sno-cone before the time was up.
The Rheem boards come with the sensors, my Nordyne board didn't, at least not from the eBay seller I got it from. The problem with Rheem is their reversing valves work backwards from everybody else, so if you want to put a Rheem demand defrost control board in a heat pump that isn't Rheem/Ruud, you have to modify the board or add relays to make it work properly. You need the demand control board, the ambient temperature sensor, and the coil temperature sensor. With demand defrost, it defrosts when the difference between air temp and coil temp gets too big. Now that propane is down around $1.20 again, the easy way to avoid defrosts is to set my switchover temp to 35-40° so it never frosts up in the first place. It still defrosts every 4 1/2 hours of running time, supposedly to return oil to the compressor. Mitch. _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
