Multiple zone air handler with recirculation line?

Question

I am having a multiple zone air handler installed. There is one condenser outside and the one handler in the attic will supply two zones with two thermostats. The air handler has a recirculation line from the outlet to the inlet. I assume this is to protect the fan if over loading when the zone dampers are not open enough.

Has anybody had problems with this arrangement? It just sounds like a great idea but complicated. Will the unit trip off on high temp in the winter if the air recirculates to much? Is there a similar problem in the summer?

Has anybody had trouble with this arrangement?

Thanks

Answer 1

A zoned system can work quite well and be very efficient as long as it's installed and programmed correctly. The control for the unit has to be set up to look for demand from either zone to bring on heating or cooling as needed. You don't want your furnace or AC running if the zones are already comfortable. The bypass you speak of will also require a damper. Some zoned systems use an electronic damper which interface with your two zones, and will modulate to maintain the desired air flow through the duct system by controlling the static pressure of the duct work. A cheaper version utilizes a static relief damper with an adjustable weight on it. The weight is adjusted so that the excess air pressure will start to force the relief damper open as the zone dampers begin to close. Make sure you get a decent air balance on your system when they start it up. It will really help the overall efficiency. Good luck with your system

Answer 2

Goobles

Answer 3

The bypass aids with maintaining static pressure in the duct when a zone system is being used.It should never trip any high limit in the furnace.You didn't mention having any cooling problems.This system works well when installed and balanced correctly.