Sudden High Energy Bills in Spokane Valley, WA

Spokane Valley has seen significant residential growth over the past two decades. A lot of that housing stock - neighborhoods near the Greenacres area, homes along the Centennial Trail corridor, subdivisions near Mirabeau Point Park - was built with builder-grade HVAC equipment. Those units are now 15 to 20 years old. They're hitting the end of their designed lifespan, and efficiency drops sharply as components age.

Here are the most common mechanical causes we find:

1. Dirty or Restricted Air Filter A clogged filter forces the blower motor to work harder to pull air through the system. The furnace runs longer to move the same amount of heat. This is the simplest cause - and the one homeowners can check themselves (more on that below).

2. Failing Blower Motor or Capacitor The blower motor moves conditioned air through your ductwork. When the motor or its start capacitor begins to fail, it draws significantly more electrical current while delivering less airflow. Your bill goes up; your comfort goes down.

3. Dirty Burners or Flame Sensor Burners coated in oxidation or debris don't combust fuel cleanly. The furnace compensates by running longer cycles to reach your set temperature. A dirty flame sensor causes the burner to cycle on and off repeatedly - short-cycling - which is extremely inefficient and hard on the heat exchanger.

4. Cracked or Degraded Heat Exchanger The heat exchanger is the metal chamber that separates combustion gases from your breathing air. When it cracks - common in older units that have been running hard - it disrupts airflow patterns and reduces heating efficiency. This is also a CO risk. It requires immediate evaluation.

5. Duct Leaks Conditioned air escaping into your attic, crawlspace, or wall cavities before it reaches your living space means the furnace runs longer to compensate. Homes near the Dishman Hills Natural Area and the Spokane Valley Mall area often have older duct systems that have never been inspected or sealed.

6. Thermostat Calibration Issues A thermostat reading the wrong temperature will call for heat more often than needed. This is easy to overlook because the system appears to be "working."

7. Aging System Efficiency Decline A furnace rated at 80% efficiency when it was installed may be operating at 65% or lower after 15–18 years of use without proper maintenance. Every percentage point of efficiency loss shows up on your utility bill.

Before you call, run through these checks. They take five minutes and may save you a service call - or help us diagnose faster when we arrive.

• Check your air filter. Pull it out and hold it up to a light source. If you can't see light through it, it's restricting airflow. Replace it with the same size and MERV rating.
• Check your thermostat settings. Make sure it's set to "Heat" and "Auto" (not "On," which runs the fan continuously). Verify the temperature setting hasn't been changed.
• Check your vents. Walk through the house and confirm supply and return vents are open and unobstructed. Furniture, rugs, and closed doors all restrict airflow.
• Check your utility bill history. Pull the last three months. Is the spike consistent, or did it happen in one billing cycle? A single-cycle spike may point to a specific event (extreme cold snap, system malfunction). A gradual climb over months points to efficiency decline.
• Listen to your furnace. Is it running longer than usual? Cycling on and off frequently? Making new sounds? Note what you observe - it helps us narrow the diagnosis.