Sudden High Energy Bills in Spokane, WA

Spokane's housing stock tells an interesting story. A significant wave of construction happened here 15 to 20 years ago - neighborhoods across the South Perry District, Kendall Yards, and Browne's Addition saw infill and new builds alongside older retrofits. A lot of those builder-grade furnaces installed during that boom are now hitting the end of their designed lifespan.

When a furnace ages, efficiency drops. But age alone isn't always the culprit. Here are the most common mechanical reasons your bill spiked:

Dirty or Clogged Air Filter This is the most common cause - and the most overlooked. A clogged filter chokes airflow to the heat exchanger. The furnace has to run longer to move the same amount of heat. Longer run times mean more fuel burned and more electricity consumed by the blower motor.

Short-Cycling Short-cycling is when your furnace fires up, runs briefly, shuts off, then fires up again - over and over. Each startup burns more fuel than a steady run. Short-cycling can be caused by an overheating furnace (often from restricted airflow), a failing flame sensor, a faulty pressure switch, or a heat exchanger problem.

Dirty Burners or Flame Sensor When burners are coated with dust or oxidation, combustion becomes incomplete. Incomplete combustion means less heat per unit of fuel - your furnace burns more gas to produce the same warmth. A dirty flame sensor causes the system to misfire and restart repeatedly, compounding the inefficiency.

Failing Blower Motor or Capacitor The blower motor moves heated air through your ductwork. When a motor is failing or its capacitor is weakening, it draws significantly more electrical current to do the same work. That shows up directly on your electric bill - even if your furnace is gas-fired.

Cracked Heat Exchanger The heat exchanger is the metal barrier between combustion gases and the air you breathe. When it cracks, the furnace's safety systems may cause it to shut down prematurely or run erratically - both of which tank efficiency. A cracked heat exchanger is also a carbon monoxide risk and should be treated as urgent.

Duct Leaks If your ductwork has gaps, disconnected joints, or deteriorated seals, heated air escapes into unconditioned spaces - your attic, crawlspace, or wall cavities. Your furnace keeps running to compensate. You pay for heat that never reaches your living room.

Aging System Losing Efficiency A furnace rated at 80% efficiency when it was installed may be operating at 65% or lower after 15–20 years of wear. The math is simple: less efficiency means more fuel to produce the same heat output.

Before you call, there are a few things you can check safely without tools or technical knowledge.

• Check your air filter. Pull it out and hold it up to light. If you can't see light through it, it needs to be replaced. A standard 1-inch filter should be changed every 1–3 months during heavy use.
• Check your thermostat settings. Make sure it's set to "heat" and "auto" - not "fan on." A fan running continuously will inflate your electric bill.
• Check your vents. Walk through the house and confirm that supply and return vents aren't blocked by furniture, rugs, or stored items. Blocked vents force the system to work harder.
• Listen to your furnace. Is it starting and stopping frequently? Running for unusually long periods? Making new sounds - clicking, banging, or humming? Note what you observe before we arrive.
• Check your utility bill history. If your provider offers a usage graph, compare this month to the same month last year. A spike of 20–30% or more without a weather explanation points to a system issue.

These checks are safe for any homeowner. Do not open the furnace cabinet, attempt to clean burners, or adjust gas components yourself.