To diagnose all the heating, ventilation, and air conditioning or HVAC problems, start repairing the visible items and then move onto the hidden components. The HVAC comprise of an air conditioner, a furnace, a ductwork and a fan attached to it. A thermostat controls them all by commanding them to switch on or off according to programmed settings. A filter resides inside the ventilation system which purifies the air before it blows throughout the house, whether warm or cold.
Start the detection of the problem in your HVAC system by checking its power supply. Then find the service panel and verify the circuit breaker has not tripped. The air conditioner and the furnace both have their individual circuit breaker or commonly known as fuse. Turn off the circuit breaker if any unit is malfunctioning. Wait for at least ten seconds and then switch it on again. Detach and replace the burnt, blown or broken fuse. Now check the thermostat for the power. Thermostat receives power by either the batteries or the electrical system. If you are using the batteries for power, replace the batteries if the unit does not have any power.
Turn the thermostat to the mode indicating ‘heat’. Set the thermostat three to five degrees above the room temperature. Check for the heat at an open register after waiting for at least half a minute. If the heat is not coming out, turn the thermostat off. Be sure that the panel door on the furnace is closed. The panel door has a switch inside it which allows the fully engaged system to operate. If the system is not entirely engaged, then the heater will not start. Open the panel door and then turn off the gas by pushing the reset button to reset the furnace. Wait for five minutes and then on the gas. Refer to the unit’s manual for additional information.
Troubleshooting Air conditioner
Switch the thermostat to cool mode. Set the thermostat three to five degrees below the room temperature. Check for the cold air at an open register after waiting for at least half a minute. Reset the AC to the circuit breaker. Check the AC for water below the unit if the air conditioner is working but does not produce cold air. Dirty coils cause the coils to freeze if there is water below the unit. Switch off the AC at the circuit breaker and wait for at least 3 hours. Then clean the coil and start the unit.
Check if the registers are open and the fan is on the thermostat. The latest thermostats come with two options i.e. on and auto. The fan uninterruptedly runs when it is set to ‘on’ mode. The fan starts with the heater at the ‘auto’ mode. Remove the filter from the cold air return. Check the filter for dirt. The cold air filters need to be clean for the system to work properly. Check out the manual if your filter is permanent. Locate the arrow pointing towards the direction of the air flow. After cleaning the filter put back the filter such that arrow is facing the ductwork side. If the filter is disposable, then replace it with a new one.