Operating mode & controls
Verify thermostat calls, reversing-valve behavior, staging and auxiliary/emergency heat logic.
Heating & cooling
Heat-pump diagnostics built around performance, not just pressure readings.
Heat pumps combine refrigeration, airflow, controls and backup heat. Black Book looks at the system as a whole so a comfort complaint is not reduced to one gauge reading.
Measured diagnosticsClear recommendationsField-tested processSouth Sound service
Diagnose firstFind the cause before recommending the fix.
Use the readingsMeasurements support the recommendation.
Explain the optionsKnow what matters now and what can wait.
Verify the resultApproved work is tested after completion.
HOW WE LOOK AT IT
More than a symptom.
A heat pump has to move heat effectively, move air through the home, respond correctly to controls and transition through heating, cooling and defrost as designed.
Indoor airflow
Filter, blower operation, coil condition, temperature split and static-pressure concerns when indicated.
Outdoor unit
Coil condition, fan operation, electrical connections and overall operating condition.
Refrigeration performance
System temperatures and operating data are evaluated in context rather than treating pressure alone as a diagnosis.
Defrost & cold-weather operation
Defrost logic, sensors and backup heat are checked when the complaint points to cold-weather performance.
Electric backup heat
Heat-strip operation and amperage are verified on systems equipped with auxiliary electric heat.
MEASUREMENTS
Readings have a purpose.
We use the measurements that fit the equipment and the complaint. Numbers are useful when they help explain what the system is actually doing.
Temperature split
Shows delivered heating or cooling performance at the air side.
Electrical load
Motor, compressor and auxiliary-heat operation can be compared with expected behavior.
Airflow / static
A refrigerant system cannot perform correctly if airflow is compromised.
System temperatures
Useful for understanding heat transfer and identifying where performance is being lost.
FROM THE FIELD
“When a heat pump is “not keeping up,” the problem can be refrigeration, airflow, defrost, controls or backup heat. The fastest path is usually to prove each part of the system instead of assuming the outdoor unit is low on refrigerant.”
That field-first approach is what the Black Book service pages are built around: real troubleshooting logic translated into plain language for homeowners.
COMMON CALLS
Problems we are called to investigate.
Weak heating in cold weatherCompare delivered heat, outdoor conditions, airflow and backup-heat operation to determine what is limiting capacity.
Outdoor unit icingDistinguish normal frost from a defrost, airflow, sensor or refrigeration problem that is allowing ice to build.
Defrost problemsVerify sensors, board logic, reversing operation and the conditions required for the system to enter and leave defrost.
Auxiliary heat not operatingCheck the call for backup heat, sequencers or relays, heat strips and actual amperage where electric auxiliary heat is used.
Mode/reversing-valve issuesConfirm thermostat command, valve control and actual system response when heating and cooling behavior do not match the selected mode.
Airflow restrictionsCheck filters, blower performance, coil condition and duct restrictions before interpreting refrigeration readings.
Control or communication faultsFollow manufacturer fault information while verifying power, wiring, sensors and communication between components.
Outdoor fan or electrical failuresTest the fan circuit, capacitor or electronics, wiring and motor operation before condemning the outdoor assembly.
FAQ
Questions homeowners ask.
Why does my heat pump blow cooler air than a furnace?
Heat pumps commonly deliver lower supply-air temperatures than gas furnaces while still heating the home effectively.
Should the outdoor unit run in winter?
Yes. In normal heat-pump heating mode, the outdoor unit is part of the heating process.
What is auxiliary heat?
It is supplemental heat used when the heat pump needs help or during certain operating conditions.
Do you service inverter heat pumps?
Yes. Inverter systems require a more control- and performance-focused diagnostic approach than simple on/off equipment.
BLACK BOOK HOME SERVICES
Need help with heat pumps?
Tell us what the system is doing and what you have already noticed.