We have a 22 year old Apollo hydro heat air handler in our attic - Model HB30241G - that has a broken coil. We replaced the A/C unit outside a couple of years ago with a brand new R-22 unit. At the time, we discussed replacing the hydro heat unit, as we were told it probably only had a few years' life left in it. Our HVAC contractor advised us that as it wasn't broke, there was no need to fix it, and we could wait for it to break before we replaced it.
Now we have been told by our current A/C service company that the HB30241G is no longer available, and that R-22 compatible units are no longer being manufactured. They have found a replacement coil which they can order for us and install, but we are concerned about how long the other parts of the unit will last. The fan in the unit has been sounding louder, and parts of the pan are rusty. They have been very helpful in tracking down the replacement coil, but this kind of hydro heat system isn't that common around here and they don't know all that much about what our other options might be, short of replacing everything (which would be very expensive.) So here are my questions, but please let us know if I'm missing something or haven't thought this through:
Can we simply replace all the parts of the hydro heat unit, even if we can't buy a whole new one any longer? Or is there some other hydro heat unit that is R-22 compatible that we could install instead? We have plenty of room in our attic, so although the current unit is one of the narrower models, we could fit something larger into the space available if we needed to do that. Or is there any other fix for this problem?