Quick answerBoiler replacement in Spokane starts with a heat-loss calculation, because most old cast-iron boilers are badly oversized. The new boiler, often a condensing model, is piped to the existing radiators or baseboard, vented through the wall or a lined chimney, and permitted. Most replacements take two to three days.
Updated September 2026
When it is time to replace a boiler
A boiler that is leaking from the heat exchanger, needs a burner and controls at once, or is more than 25 years old is usually past the point where repairs make sense. Many older boilers were sized for drafty houses that have since been insulated, so they short cycle and waste fuel.
A modern condensing boiler captures heat from its exhaust and modulates its flame to match the load. It works best with lower water temperatures. We check whether your radiators or baseboard can heat the house that way before recommending one. Then we set the outdoor reset so the boiler runs only as hot as the weather requires.
What drives boiler replacement cost
Two replacement paths
Condensing boiler upgrade
A condensing boiler hangs on the wall, vents through PVC or polypropylene pipe to the outside, and drains its acidic condensate through a neutralizer. We size it from a heat-loss calculation. Primary and secondary piping gives the existing system the flow it needs, and outdoor reset lets water temperature drop on mild days. Large cast-iron radiators are well suited to condensing boilers because they can heat a room with cooler water, which keeps the boiler in its efficient condensing range for most of the season.
Combi boiler installation
A combi boiler heats the house and makes on-demand hot water in one wall-hung unit, which frees up the space an old boiler and a water heater used to take. It suits smaller homes and households that do not run several showers at once, because hot water output has a limit. We size it for both the heating load and your hot water flow, and add a mixing valve. We also check water hardness. Scale shortens the life of the domestic heat exchanger without treatment.
Boiler options side by side
| Condensing | Combi | Non-condensing cast iron | |
|---|---|---|---|
| Efficiency | Highest | High | Lower |
| Hot water | Separate tank or indirect | Built in, on demand | Separate tank |
| Venting | Sidewall plastic pipe | Sidewall plastic pipe | Chimney |
| Best for | Most homes with radiators | Smaller homes | Steam systems, some old piping |
Boilers in Spokane's older housing
Spokane's median home dates to 1961, and about a quarter were built before 1940. In Hillyard a large share of homes went up between 1940 and 1969, when many original boilers were installed. Many of those boilers were sized before the houses got new windows and insulation, which is why a heat-loss calculation almost always points to a smaller boiler than the one coming out.
How a boiler replacement goes
- 1
Heat-loss calculation
Room-by-room load to size the new boiler.
- 2
Check the emitters
Radiators and baseboard measured for low-temperature heat.
- 3
Quote and permit
Written price, permits filed.
- 4
Drain and remove
System drained, old boiler disconnected and removed.
- 5
Install and pipe
New boiler mounted, piped, vented and wired.
- 6
Fill and purge
System refilled, air purged from every zone.
- 7
Commission
Combustion tested, outdoor reset set, inspection booked.
How long you go without heat
A straight boiler swap is usually two days, and three when venting or piping changes are extensive. Heat is off from the moment we drain the system until the new boiler is commissioned. In cold weather we bring portable electric heaters for the main rooms. We also schedule the job to finish before a forecast cold snap.
Boiler replacement questions
Should I replace my boiler or switch to a furnace?
If the radiators or baseboard work well, a new boiler keeps that comfort and avoids adding ductwork. Switching makes sense mainly when you also want central cooling.
Will a condensing boiler work with my old radiators?
Usually yes. Large cast-iron radiators work very well with lower water temperatures.
Can a combi boiler supply my whole family's hot water?
For most small households, yes. Homes that run several showers at once may need a boiler with an indirect tank instead.
How long does a new boiler last?
A well-maintained modern boiler typically lasts 15 to 20 years or more, with annual service.
Does a boiler replacement need a permit?
Yes. Boiler replacement needs mechanical and gas permits, which we file.
Other furnaces, boilers & electric heat services we handle
Furnace Repair
Answered 24/7, parts on the truck.
Furnace Repair detailsEmergency Heating Repair
Answered 24/7, parts on the truck.
Emergency Heating Repair in SpokaneFurnace Tune-Up
Seasonal service, fewer breakdowns.
How we handle furnace tune-upKeep the radiators. lose the old boiler.
Call about boiler replacement in Spokane, WA.
