I'm planning to buy a furnace - just one question:
I need the type of furnace that vents horizontally through PVC. When selecting the model, is there some indication of this that I should be looking for? Or is it just something like all furnaces above 95% efficiency can do this? Or...?
Generally any high efficiency ("90+") gas furnace is a Cat IV appliance that can be vented with PVC. But a word of caution if you are in DIY space with this (as I was once upon a time)... it isn't as simple as it sounds. There are very specific requirements based on the manufacturer and model for piping size, length, etc., as well as code requirements for vent pipe slope, and location of vent and intake terminations.