Furnace Replacement in Whitehall, MT

Four things move the answer toward replacement: a cracked heat exchanger, a repair cost above roughly half the price of new equipment, an age past twenty years with parts getting scarce, and a pattern of repeat failures across different components. Any one of those deserves a conversation; two together usually settle it.

Everything else is often worth repairing, and we will say so. A furnace that needs an igniter and a capacitor is not a candidate for replacement just because it is fifteen years old.

A replacement is the one chance to fix what the original install got wrong. We resize the plenum transition if the old one was choking airflow, add a properly sized filter rack, correct gas pipe sizing, redo vent runs to current clearance requirements, and reroute condensate so it cannot freeze in unheated space.

We also revisit sizing rather than matching the old nameplate. Homes get insulated, windows get replaced, basements get finished — the load today is rarely the load the previous furnace was chosen for, and copying it forward is how oversizing gets inherited.

An 80% furnace is simpler, cheaper to install, and vents through an existing chimney or B-vent. A 90%-plus condensing furnace costs more up front, needs PVC venting and a condensate path, and returns the difference in fuel over a long Montana heating season. Which one wins depends on your fuel cost, how long you plan to stay, and what your venting situation allows.

We show you both numbers with your actual usage rather than pushing the highest-margin option. Variable-speed blowers and two-stage burners get the same treatment: what they do for comfort here, and whether the premium pays back for your house.