Winter is a time for heating, not cooling, and it is vital that the HVAC systems of your customers are operating properly and keeping their homes warm and comfortable during the cold months that are coming. However, the issue of an HVAC system blowing cold air instead of warm can appear, creating quite a poor situation for the homeowners in question.
There are several reasons why your customers’ HVAC unit is blowing cold air out. Some of them are due to slight oversights on your customers’ behalf, some are banal and very easy to fix, while others take some time to detect and resolve adequately. Consult your furnace manual for more specific details, but here are some general guidelines.
Let’s take a look at the most common underlying causes of an HVAC system blowing cold air instead of cold, and what you can do to quickly deal with the matter so your customers can start feeling comfortable in their homes as soon as possible.
1. No time for warming up
The simplest cause of an HVAC system blowing cold air is that the heater hasn’t had sufficient time to adequately warm up. If your customer has just turned the system on, there is a big possibility that the system will not be able to start operating at full capacity immediately. Patience is key, and the heater should start operating normally within 10 minutes.
2. Thermostat problems
If your customer has allowed plenty of time for the HVAC system to warm up, but it’s still producing cold air, then the problem might be with the thermostat. There are three most frequent issues with the thermostat that will cause insufficient heating from the HVAC unit:
- Thermostat is set to “on”, making it run even when it’s not on heat cycle, which means cold air will blow.
- Weak or dead batteries in the thermostat which makes it manage temperature poorly.
- Improperly programmed programmable thermostat.
3. Heat pump problems
If your customers have a heat pump, that could be the problem behind cold air. If snow has covered the unit, or if the heat pump has iced over, the entire heating system can start blowing cold air instead of hot. Also, other issues that could be causing problems with the heat pump are:
- Faulty metering device
- Bad valves
- Low refrigerant
4. Tripped breaker
If your customers own an electric furnace, one of the causes of cold air could be a tripped breaker. It can prevent warm air from circulating around your customers’ homes, causing a low flow of cold air. Also, a tripped breaker can prevent gas burners from igniting and heating the air necessary to heat a household.
5. Pilot light
The pilot light on a gas furnace will go out if the system is experiencing gas supply interruption. This can also be the underlying issue that is causing cold air circulation. Sometimes, your customers alone can relight the pilot light, but it is always advisable to consult you for professional assistance.
6. Dirty flame sensor
If the flame sensor gets dirty, it can prevent the system from recognizing if the burners are turned on and stop them from igniting, resulting in cold air circulating in your customer’s household. This is also a matter best left to professionals to handle.