Knowledge Center
HVAC Resource Hub
Your central library for heating, cooling, and indoor air quality guidance — written by Chicago's HVAC experts.
Year-Round Prep
Seasonal Guides
Fall Furnace Prep
Replace filters, test your thermostat, and schedule a furnace tune-up before the first cold snap hits Chicago.
Winter Boiler Checklist
Check system pressure, bleed radiators, and verify zone valves are operating before temperatures drop below freezing.
Spring AC Tune-Up
Clean condenser coils, check refrigerant levels, and test cooling performance before summer heat arrives.
Summer Cooling Efficiency Tips
Change filters, clear the condenser, set smart thermostat schedules, seal air leaks, and close blinds during peak sun hours to stay cool and save energy.
DIY Guidance
Maintenance Tips
Filter Replacement Schedules
1" filters: every 1–3 months. 4–5" media filters: every 6–12 months. HEPA filters: annually. Check monthly during peak heating/cooling season.
Boiler Pressure Basics
Normal hot water boiler pressure is 12–20 PSI. Below 10 PSI, the boiler may shut off. Above 30 PSI, the pressure relief valve may open. Check the gauge monthly.
Mini-Split Cleaning
Clean or replace air handler filters monthly. Wipe down the indoor unit with a damp cloth. Have a technician clean the coils and check refrigerant annually.
Radiator Bleeding Instructions
Turn off the boiler. Use a radiator key to open the bleed valve at the top of the radiator until water (not air) flows out. Close the valve and check system pressure.
Make Informed Decisions
Homeowner Education
Hydronic vs. Forced Air
Hydronic heating uses water to distribute heat through radiators or in-floor tubing — quieter, more even, and often more efficient than forced-air systems.
When to Repair vs. Replace
If your system is over 15 years old and repair costs exceed 50% of replacement cost, replacement is usually the better investment. Ask DsAir for a free assessment.
Understanding SEER2 Efficiency Ratings
SEER2 is the updated efficiency standard for ACs and heat pumps. Higher SEER2 means lower energy bills, better humidity control, and more precise temperature regulation. 13–17 SEER2 is standard; 17–18 is high-efficiency; 20+ SEER2 is premium variable-capacity. Lennox's SL28XCV reaches up to 28 SEER2.
Choosing the Right Lennox System
Match system size to your home's square footage, insulation, and duct layout. DsAir performs Manual J load calculations to ensure proper sizing every time.
Have a question not covered here? Call DsAir directly — we're happy to help.
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