I bought a home (pre-fab = mobile without wheels) that has a Coleman
Evcon model EB15B furnace. Until I upgrade to a heat pump, I'd like to
get the most of what I can out of this fuel hog.
When the thermostat calls for heat, the fan blows and 2 of the three
heaters in it have power going to them. (the limit switch is OK to the
one that doesn't turn on.) (I'm guessing the third may be for if it's
very, very cold?) Anyway, when the room temperature rises, the
thermostat opens, the fan speed slows, and the two heating elements are
still getting full 240VAC. After about a minute it shuts off
completely. This seems strange to me, I again am guessing that the
heaters should turn off and the slow fan speed makes good of what heat
is in the system, mainly the two hot heating elements. But like I said,
the heaters stay on. Is this not working correctly?
All three heating elements are wired to what the wiring digram calls a
"sequencer", it looks like a combination of two relays/heat sensor
combinations, mounted on a plate with the numbers: 15SH41 309509
3115-357 H1-110 C1-110
So is the sequencer bad? Which of those numbers are the actual part
number I would need to get a replacement? Can I get a replacement? Where?
By the way I've been playing with 240VAC for almost 30 years now and I'm
not going to fry myself.
Thanks in advance,