I've got an open-loop 6 ton WaterFurnace Legend at a summer house in Northeast Pa.

I'll use cooling maybe a week a year. I keep the heat at 55-60 during the winter, except for 4-6 vacation weekends.

There are two zones. My contractor has told me that we should use a PSC blower. He says an ECM blower won't work with the WaterFurnace zone system. As the zone system balances the supply air the ECM blower will try to rebalance it, creating a feedback loop. In addition, he says the ECM blower would not be cost effective ($0.14/kwh).

This doesn't sound right to me. I'd appreciate any help.