During the past few heating seasons we have experienced an unusual condition within the software of our WarmFlo II plenum heaters. For some unknown reason, -01° F is written into the stage one outdoor temperature disable section of the software. We have come to the conclusion that a key factor of this issue is due to a resistor that was added in 2008 to help assist in troubleshooting. This resistor may cause a slight variation in control voltage.
Please click here for details regarding this field service bulletin. If you have any further questions please do not hesitate to contact us.