Residential No-Cool — Split System Not Cooling
- Interactive decision labs
- Built by working technicians
- Path-based verifiable certificate
- Exam preparation only
- Worldwide online
Residential HVAC Service & Diagnostics
~14 min
foundation
The call
Homeowner says the air handler is blowing but the house has been getting warmer since yesterday afternoon.
- Equipment
- 3-ton R-410A split system, 9 years old, single-stage condenser, gas furnace air handler
- Ambient
- 96°F
- Site notes
- Thermostat is set to COOL at 72°F, space is 84°F. Indoor blower runs. Outdoor unit is silent when you walk up to it.
Decision 1 of 4
You are standing at the outdoor unit on a 96°F afternoon. Nothing is turning.
What is your first action?
Where this lab sits
This is one module lab from Residential HVAC Service & Diagnostics. The full path adds sealed systems, defrost, rack-system orientation and natural-refrigerant safety, each ending in a lab like this one.
Open the full pathNext lab: Residential No-Heat — Gas Furnace Short Cycling on IgnitionNext lab: Frozen Coil / Airflow RestrictionNext lab: Superheat / Subcooling DecisionNext lab: Walk-in Cooler Not Holding TemperatureNext lab: Ice Machine Not Making IceNext lab: Reach-in / Prep Table Not Holding TemperatureNext lab: Walk-in Freezer Defrost FaultNext lab: Natural Refrigerant Safe-Handling DecisionNext lab: Rooftop Unit Not CoolingNext lab: RTU Economizer Stuck — No Free CoolingNext lab: RTU High Static — Low Airflow and Poor CoolingNext lab: RTU Gas Heat — No Heat / Ignition Fault