I'd appreciate some help in deciding which Coleman heat pump to select. I asked for bids from three contractors, received two, and have decided against the contractor who bid Trane equipment. That leaves me with one contractor I like, and he has proposed three options.

We have a 1650 sq ft house located in the Puget Sound area of Washington state. We use the heat pump for heating (cooling is rarely needed - a day or so every few years) and have electric service. We're replacing an approximately 19-yr old Coleman system that needs expensive repairs.

The contractor we like has proposed two alternatives: 1) Coleman "LX Series" THJF030 (15 SEER) with MV12B blower and Honeweill Vision Pro Touch Screen Thermostat. 2) Coleman "Echelon Series" HC6B030 (16 SEER) with same blower and Echelon Touch Screen thermostat. Both are 2.5 ton units.

3) I asked for and also have a proposal for a 3 ton Echelon HC6B036 (17.3 SEER) and blower MV16C. (Capacity of our existing system is not known--model number is illegible.)

How much difference in operating cost does a 1 SEER difference make?

Should I have the lock-out control enabled? How will that affect operating cost? (We have lock-out on our existing system.)

What other factors should I consider in evaluating which heat pump to select?

Estimator said he thought 2.5 ton was right size for the house, but 3 ton would not be too big. The first contractor didn't bother to tell me the capacity of the proposed Trane unit--I'm trying to find out what size he proposed. Can I compare tons of capacity between Trane and Coleman, or are those apples and oranges?

Thanks for your help!