Nordine (Miller) Oil Furnace cycles MANY times on cool down
Posted: Sun Jul 05, 2009 8:22 pm
I have a newer Miller Oil Furnace (now Nordine), Model # CMF2-80(PO), S# cma06/20058. It works great... once the burner shuts off, the fan continues to run until it reaches the low limit setpoint - but then it will cycle the circulating fan on and off between 9 to 12 times before it shuts down completely... takes about 1.5 - 2 minutes of this annoying cycling to turn off completely. The blue limit (electronic) setpoint label says F115-20F (part # 626552). I'll assume it takes the heat exchanger temperature down to 115F, with a 5 degree variance? Is this a flaw in the Miller design or do I have a bad limit switch or ? Would a different switch with a greater variance stop this problem? Walter Cordes, Cedarville Michigan.