[ortusdux]

This model can be ducted with standard 8" ducting. It is possible to have it draw warm air from outside or vent the cold air out of the house. You can get fancy and install baffles that you switch seasonally. A properly ducted system will be more efficient because you won't be putting artificial house heat into the water or heating the house more to offset the cooling.

[nkurz]

I installed it thinking I'd install ducting if necessary. But as you might guess, in the winter in Vermont there aren't a lot of available sources of warm air other than the those you create through heating. And if I vent to the outside, the resulting depressurization will just cause the rest of the house to suck in even colder outside air. The basement itself derives enough ground heat to stay above freezing, but heat pump efficiency drops as you get close to freezing.

Currently, I think I'll probably connect to an intake floor register from above, so it has better access to warmer air. I'll be trading off more firewood for less electric, which is probably a win. I'll probably also exhaust the cooler air back into the house level, on the theory that this will help a little in the summer. I'm guessing the downside will be increased noise. It's a quiet house to begin with (woodstove with no forced air) and I'm loath to make it noisier.

Do you know if there is any benefit to going with the model specific ducting kit? Or can one just buy off the shelf?

[ortusdux]

Off the shelf should be fine. It's rated for 340' of ridgid pipe or 125' of flex. I've seen people zig-zag the ducts to help reduce the noise