We're replacing a '60s era gas furnace and older hot water heat (gas). We expect to go with a hybrid system--heat pump and gas furnace--and a tankless hot water heater. In the last year or two Rinnai came out with an air handler that works in concert with their tankless water heater to provide home heating. We expect to rely on the heat pump nearly year 'round to heat our home (Western Washington has mild winters). Since we expect to install a Rinnai tankless anyway, we like the idea of using the Rinnai for backup heat (in place of a new gas furnace). The contractors here have no experience with these systems. The contractors who already install Rinnais are happy to consider their air handler, but I'd like to hear from someone who has used these systems.
We're looking at a Trane XL14i or XL15i for the heat pump side of things. Any insight into how well the Rinnai air handlers work and how well one will work in concert with the Trane heat pump? Since these are new, what about their quality, reliability and efficiency? Also, are these good enough air handlers to utilize the efficiency of the heat pump? Any insight would be great.