The first sign most people realize means that the heating and air conditioning ventilation – HVAC – system is not working tends to be when the system shuts off unplanned or won’t start.
When the failure occurs, people feel no choice but to call the heater or AC repairman to solve the problem. However, there are number of steps a person can follow with HVAC troubleshooting before picking up that phone and spending $80 or $100 just for a visit and diagnosis.
These issues can include things as simple as:
- No power to the HVAC system
- Popped circuit breakers
- A faulting thermostat unit
- Bad relays or AC coils, and
- A dirty air duct filter
Electrical Power HVAC Troubleshooting
The most likely cause of a shut-off or a non-responding HVAC unit tends to be the power source. HVAC units take an incredible amount of power, and when a whole neighborhood is running their ACs, the entire electrical grid can get strained. If the unit goes out during the day, the first thing to check is if other electrical tools and appliances in the immediate residence are also not working. The likely culprit is a power outage.
However, some electrical sockets may be working just fine while the HVAC unit is not responding. In this case the issue may be a popped circuit breaker. Breakers are a required safety unit that immediate cut electrical power to a particular section or appliance in home. This helps prevent catastrophic fires that occur from electrical malfunctions or loads that get too hot for the wiring carrying them.
When the breaker pops, the power will be immediately cut to the appliance connected to that particular circuit. Resetting the breaker at the house fuse box will connect the power again, but the breaker will continue to pop if the problem is actually being caused by a faulty connection or wiring. Thus a resetting only solves half the problem if the HVAC works again.
The best place to check for problems involves the wiring going to the HVAC unit from the house. Wiring and connectors are easy to inspect for exposure and open insulation. However, they should only be checked and touched with the power completely turned off, which can be done by purposely shutting off the dedicated circuit breaker.
If insulation is exposed or connectors are loose or falling apart, having a licensed electrician perform the repairs is the best course of action. He can then also check that there are no other wiring problems before resetting the circuit and committing the HVAC again to performance.
A secondary issue that can trip up an HVAC involves a faulty electrical signal from the thermostat sensor. HVAC systems are designed to turn on and off based on the settings of the thermostat control that is connected to them. Something as simple as a battery pack in some sensor units can make it look like the HVAC unit is failing when it isn’t. This problem is usually manifested by a code or symbol display on the sensor screen signifying the dying battery problem. Swapping in a new set of battery cells solves the problem.
If the thermostat, on the other hand, doesn’t use a battery yet the sensor is out, then there is an electrical wiring issue to the sensor pad. Again, the service of the licensed electrician is then the best course of action. Fiddling around with house wiring as an amateur is just a bad recipe to get electrocuted or cause a problem that manifests later on.
Evaporator Problems HVAC Troubleshooting
If the air conditioner runs but doesn’t seem to be putting out any cold air, then there is an issue with the evaporator. Easy-to-check issues start with the most visible and obvious. When the unit is turned on, the fan should be spinning on the top of the AC unit. Most home AC units are on the ground level next to the house. If the fan is not spinning, that’s the first cause of the problem.
Where the fan is spinning but the coils are completely covered with dust, dirt, or plant growth, the AC will have a significant challenge in producing cool air. The coils should be completely picked clean of debris and washed with water and soap.
The evaporator fan relay can also be a problem source as well. A quick check of power commitment to the relay will find whether it is allowing the connection through or not. If the relay is bad, the power won’t connect and the fan won’t work either.
Duct Problems HVAC Troubleshooting
A simple but significant problem that can hamper air flow for an HVAC involves the air filter. A simple thing, the filter catches all the bugs and dirt that get blown through the HVAC system as it runs and sucks air from the outside. However, while filters should probably be replaced every one to two months, depending on the surround air cleanliness in the community, most people tend to forget or delay. When the filter gets so clogged up that it can’t let air through, the HVAC can run and not produce any warm or cold air where it matters. A simple removal of the old filter, brushing out the residue around, and inserting a new filter can check if this problem is the source of frustration.
When It Is Time to Call for Help
If going through all the hvac troubleshooting steps the HVAC problem is still not solved. Then it’s time to check the capacity and pressure. The problems can range from a refrigerant leak to a malfunctioning heater furnace. None of these issues are they type of problems someone can fix with a few basic garage tools and duct tape. An expert HVAC repair is in order and should be called when possible.
