HVAC & Heating

Air Conditioning

• AC Condensate Drain Clogs and Overflow Shutoffs — Where the water dripping from your AC comes from, why the condensate line clogs with algae, the vinegar-and-vacuum maintenance routine, and the float switches that prevent ceiling stains.
• Frozen AC Coils: Refrigerant, Airflow, and Diagnosis — Why an air conditioner ices its evaporator coil: the two causes behind every case, the thaw procedure, and how to tell an airflow problem from a refrigerant leak.

Boilers

• Boiler Systems and Radiators: Basics and Bleeding — How hydronic heat works, the difference between steam and hot-water systems, why radiators gurgle and run cold on top, and the bleeding procedure that fixes it.

Controls

• Thermostat Wiring Basics for Homeowners — The letter-coded low-voltage world behind the thermostat: what R, W, Y, G, and C wires do, the C-wire problem with smart thermostats, and safe swap practice.

Distribution

• Ductwork Leaks: Finding and Sealing Them — Why duct leakage is the largest invisible HVAC loss in most houses, where ducts leak, the mastic-not-duct-tape rule, and the room-by-room symptoms that point at leaks.

Furnaces

• Cracked Heat Exchangers: The Serious Furnace Problem — Why heat exchanger cracks matter, how they actually form, the honest limits of flame-and-smell diagnosis, how the condition is confirmed, and the repair-versus-replace math.
• Furnace Filters: MERV Ratings and Change Schedules — What MERV numbers actually measure, the airflow tradeoff nobody mentions, matching filter depth to the system, and the change schedule by filter type and household.
• Furnace Short Cycling: Causes and Diagnosis — Why a furnace starts and stops in quick bursts: airflow starvation and the high limit, flame sensor dropout, thermostat placement, oversizing, and how to tell them apart.
• How a Forced-Air Furnace Works — The sequence of operation inside a gas furnace: thermostat call, draft inducer, ignition, heat exchanger, blower, and the safety chain watching all of it.

General

• HVAC Sizing: Why a Bigger System Is Not Better — What oversized furnaces and air conditioners actually do to comfort, humidity, and equipment life, why Manual J load calculations exist, and how to buy the right size.

Heat Pumps

• Heat Pumps in Cold Climates: What to Expect — How modern cold-climate heat pumps keep working below zero, the defrost cycle and its steam, backup heat strategy, and the ownership habits that keep efficiency honest.
• Mini-Split Systems: Operation and Maintenance — How ductless mini-splits work, why their filters need washing monthly, the mold-on-the-blower-wheel problem, condensate care, and what belongs to the technician.

Safety

• Carbon Monoxide and Combustion Appliances: Safety Basics — Where CO comes from in a house, the appliances and failure modes behind exposures, alarm placement and lifespan, and the difference between alarm response and prevention.
• Chimney Flues and Venting for Gas Appliances — How gas appliance venting works through chimneys and B-vent, the orphaned water heater problem after furnace upgrades, liner requirements, and the inspection points that matter.