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WestexJoe
Nov 14, 2007, 12:24 PM
Question 1: What do the labels mean and what are the intended destinations for furnace controller board connections marked HS1, FS, IND, M1, M2, & TWIN?

Question 2: Assuming the "M1" & "M2" are for two fan speeds. Which speeds should be used on a 3-speed motor if the controller board only has 2-speed capability?

Question 3: There are also terminals on the controller marked "HEAT" & "COOL", I'm assuming the "COOL" is a 24V for the A/C compressor unit. Where would "HEAT" connect to?

Bought a used gas furnace at a junk dealer for a buck. It's configured for running propane. Want to install it in my shop for heat. No wiring diagram since the main cover is missing (will make one later).
Cleaned it up & checked all electrical components as I went. All looks great except for needing a new 30A contactor and access panel lock-out switch (someone destroyed?? ).
Unit had obvious signs of previous repair efforts, the fan motor & start capacitor are brand new but had major wiring errors to the controller board from the fan motor, 24V transformer and contactor. Having found no evidence of anything being fried or even hot, it looks like the repair efforts were stopped before AC power was actually applied.
All the wires going to the gas valve, igniter, safety limit switches & flue exhaust components are intact. New fan motor is a 1/3hp 115V 1ph three speed, all legs check out good with an ohm meter. 24V transformer is good. Controller board T-stat connections are W, G & R. Old fan motor probably failed from being out of balance since the squirrel cage fins were totally plugged up with paper and layers of dust.

Looks like a fairly modern unit with forced air exhaust, automatic igniter and multiple gas-shutoff safety switches. I'm pretty sure the unit is Amana, controller board p/n is 9611B no obvious damage. Trying to get any info from Amana has proved fruitless so far.
TIA

T-Top
Nov 14, 2007, 05:43 PM
HSI- hot surface ignitor,FS- flame sensor,IND- inducer motor,M1 and M2- for blower speeds not used, Twin- only used when running two furnaces at once with one thermostat, Cool- high speed blower, Heat- low speed blower.