Top 5 Ways Bothell’s Wet Winters Can Damage Your HVAC System (And How to Prevent It)

Living in Bothell means embracing the Pacific Northwest’s signature wet and chilly winters. While the rain keeps our landscape lush and beautiful, it can create unique challenges for homeowners—especially when it comes to your HVAC system.

Understanding how Bothell’s damp climate affects your heating and cooling system can help you avoid costly repairs, stay comfortable all winter, and even improve your energy efficiency. Here’s what you need to know about protecting your HVAC system during Bothell’s wettest months.

IssueSeverity RankImpact on SystemPotential Repair Cost if Not Maintained
Frozen Heat Pump Coils1Reduces heating efficiency and can cause long-term compressor damage.$500–$1,500 (for defrost board or coil repair)
Moisture Corrosion in Outdoor Unit2Leads to rusted components, electrical issues, and system failure.$1,000–$2,500 (depending on part replacement)
Poor Indoor Air Quality from Humidity3Promotes mold/mildew growth in ductwork and reduces air quality.$300–$700 (duct cleaning and filter changes)
Condensation in HVAC System4Increases risk of rust in internal components and system inefficiency.$500–$1,000 (ventilation repair or part replacement)
Overworked System from Cold Temps5Causes wear and tear, leading to premature component failures.$200–$1,000 (depending on repairs needed)

1. Moisture Can Damage Your Outdoor Unit

Rain, high humidity, and even snow can take a toll on your outdoor HVAC unit. Prolonged exposure to moisture can lead to rust, corroded components, or even electrical issues. Debris from heavy winds—common in winter storms—can also clog or damage the unit.

How to protect it:

  • Make sure your unit is elevated and clear of standing water.
  • Regularly check for debris like leaves and branches.
  • Consider installing a protective cover for the winter months—but make sure it allows airflow to prevent mold and mildew buildup.

Some affordable AC Covers to stop debris:

  1. Modern Wave
  2. Cosfly
  3. Mrrihand

2. Freezing Temperatures Can Cause Heat Pump Issues

Bothell winters typically hover in the 30s and 40s, but cold snaps can dip below freezing. For heat pump users, this can mean frozen outdoor coils or reduced efficiency. Excess moisture combined with freezing conditions can turn into ice on your heat pump, reducing its ability to properly heat your home.

How to address it:

  • Check your unit for ice or frost buildup regularly.
  • Ensure your heat pump’s defrost cycle is functioning properly.
  • If icing persists, schedule a maintenance check with Cascadia Comfort to avoid long-term damage.

3. Increased Humidity Can Lead to Indoor Air Quality Issues

Bothell’s damp winters often result in higher indoor humidity levels, which can create a breeding ground for mold, mildew, and bacteria in your ductwork. This not only affects your HVAC system but can also impact your family’s health.

How to fix it:

  • Install a whole-home dehumidifier to regulate indoor humidity levels.
  • Change your air filter regularly to prevent the buildup of allergens and pollutants.
  • Schedule annual duct cleaning to ensure clean and efficient airflow.

Some great mold sprays below:

  1. RMR-86 Instant Mold Remover
  2. Nu-Calgon Evap Foam
  3. Frost King Foam coil cleaner

4. Overworked Systems Can Increase Energy Bills

When Bothell temperatures drop and the rain keeps coming, your heating system has to work overtime to maintain a cozy indoor temperature. This increased workload can lead to higher energy bills and a greater risk of breakdowns.

How to prevent it:

  • Seal leaks around doors and windows to keep warm air inside.
  • Invest in a programmable or smart thermostat to manage your heating schedule more efficiently.
  • Schedule a tune-up with Cascadia Comfort to ensure your system is running at peak performance.

5. Poor Ventilation Can Cause Condensation Problems

Older Bothell homes, which are common in the area, often have poor ventilation. This can lead to condensation building up on windows, walls, and even within your HVAC system, increasing the risk of rust or mold.

How to improve ventilation:

  • Ensure your HVAC system has proper airflow by cleaning or replacing filters regularly.
  • Add ventilation fans in key areas like kitchens and bathrooms.
  • Consult Cascadia Comfort about upgrading your system to improve ventilation and airflow.

Why Cascadia Comfort is Bothell’s HVAC Expert

At Cascadia Comfort, we understand the unique challenges Bothell homeowners face during the winter. Our team is dedicated to providing reliable, expert service to keep your home warm, dry, and comfortable, no matter how much rain falls.

Here’s why Bothell residents trust us:

  • Local expertise: We know the Pacific Northwest’s climate inside and out.
  • American Standard Dealer: We install durable systems built to last through wet winters.
  • 5-star service: Our customers love our fast response times and friendly technicians.

Stay Ahead of Winter HVAC Issues

Don’t let Bothell’s wet winters take a toll on your HVAC system. Whether you need a quick repair, a full system inspection, or a new installation, Cascadia Comfort has you covered.

Contact us today to schedule your winter tune-up and keep your home cozy and worry-free all season long.