Why Has Your Split System AC Started Blowing Suspiciously Warm Air?

The "split" in a split system air conditioner is a physical one. It's split into two connected sections: the wall-mounted section inside your home and the outside section. There's another split that the system offers, and that's the temperature of the air that it blows into the room. A split system air conditioner offers both heating and cooling options, which is a very handy fact to remember when your system starts blowing suspiciously warm air into your home.

Manual Adjustment

Sometimes this discrepancy is the simplest of problems with the simplest of solutions. Has someone manually adjusted the desired temperature? If so, make the necessary adjustments to the remote control and get back to enjoying chilled air.

Accessing the Filters

When the temperature setting is correct, yet the wall-mounted unit continues to blow warm air into the room, you have a more serious issue. It may not be especially serious just yet, and you need to think about when you last cleaned the unit's filters. The wall-mounted unit should have a large hinged panel that pivots upwards. Once opened, the filter should be visible, and it may be visibly dusty. 

Cleaning the Filters

You can start by vacuuming it in place, and then remove it (it should snap in and out of position). Take it outside and give it a shake to remove residual dust. It now needs to be gently washed in warm, soapy water and allowed to dry. It can then be reconnected to your AC. How does cleaning a filter help an inconsistent thermostat setting?

Air Flow

Dirty filters lead to impeded airflow, which can cause the unit to overheat, creating an obvious outcome—the unpleasantly warm air that's being directed into the room. Cleaning your unit's filters (which should be a regular part of the unit's maintenance) can make a big difference, yet the problem could persist, indicating a potential issue with the valve that determines whether the unit produces warm or cool air. 

Reversing Valves

Whether the unit heats or cools is regulated by a component called a reversing valve, which is controlled by a mechanism that switches between these two modes. The production of hot air when the thermostat is set for cool air suggests damage to the reversing valve or its switch mechanism. There could also be a refrigerant leak in the unit, meaning that the gas it relies upon for its cooling function has been depleted. 

Basically, if the thermostat's settings haven't been changed, and the unit's filters are clean, the problem requires a professional assessment—sooner rather than later. The more you attempt to operate a unit with a damaged heat pump or a refrigerant leak, the more operating stress the unit will experience.

About Me

Helpful and Hopeful HVAC Tips

Hello and welcome to my blog. My name is Leo. As a small-business owner and a dad who likes to help reduce the family's expenses as much as possible, I've done a fair bit of tinkering with my HVAC system, both at home and work. I've learnt a lot, including when to call in the pros. Want to get helpful, hopeful, actionable tips for dealing with your HVAC system? Then, this blog is the place. My two daughters both recently graduated uni and are living on their own, and I've transitioned to part-time at work, leaving me a lot of extra time to do things like write. I hope you like the posts.

Latest Posts

4 October 2023
As a homeowner, one of the highest priorities is to keep homes comfortable. One essential aspect of that comfort is regulating the temperature. Whethe

23 June 2023
The "split" in a split system air conditioner is a physical one. It's split into two connected sections: the wall-mounted section inside your home and

14 March 2023
Are you tired of constantly switching between heating and cooling systems in your home or office? It can be a very frustrating chore that many people