Compressor fails, but the furnace motor is still running strong. Until a repair person arrives, flip this convienient power take off switch and through a complex series of chains and cogs power is returned to the outside compressor. The result is dimminished AC but still enough to cool several rooms and prevent HEAT induced madness.-- Antegrity, Aug 30 2005 Sounds like an expensive mechinism, as you'd have to custom fit each one. Why not just have a spare motor right next to the first one, with a belt drive, minus the belt, until it is needed? Install the belt, flip a switch: as good as new, and cheaper than this, I bet.-- oxen crossing, Aug 30 2005 So it's not about having a backup hb account then?-- wagster, Aug 30 2005 Or an air conditioner that only engages in reverse gear?-- normzone, Aug 30 2005 AC's last time I checked, don't have gears. Since you need the furnace motor to run the AC as well as a motor to run the compressor outside why have spare motors?-- Antegrity, Aug 30 2005 Ouch. You don't know how AC systems are put together, do you? 1. The "furnace motor" is the fan motor, and is already sized appropriately to its job. Ask it to do more, and it won't. It will fail too, and then you'll have no fan, either.
2. Often the fan is inside the building, the compressor for the AC is almost always outside. Those chains and gears and probably driveshaft and God knows what else are going to have a long, noisy ride.
3. The AC compressor motor is inside a hermetically sealed can, to prevent leaks of refrigerant into the atmosphere. Some refrigerants run, on the high press. side, at as much as 300 psi and more depending on what you're asking them to do. Running a shaft to a pulley out through the can is asking a lot from the seal. Auto AC systems tend to fail when this seal dies, letting refrigerant out and moisture in.
Much easier, and smarter, would be a truly redundant outfit with two complete AC compressor/ evaporator/ condensor systems. If one fails, the other continues to provide (reduced) service. While both are operational, one or both can be used as necessary to provide the most economical operation. This idea gets even better when adapted to multi-speed scroll compressors.-- elhigh, Sep 01 2005 random, halfbakery