Pay attention immediately if the air coming from your vents has a burnt aroma. That acrid smell could be caused by one of several things, some worse than others.

If you also notice that your air conditioner is sending out warm air instead of cool air, your system may have jumped a track and turned on the heater.

Possible causes

• Debris, dust and contaminants build up over time if the system isn’t cleaned. Then the dust etc. can begin burning off.

• The motor or an electrical component may have gone bad.

Check that filter

As usual, the HVAC filter is suspect No. 1 when it comes to finding the source of a problem.

Is the filter dirty? Clean or replace it. This would be a quick, happy solution.

But if the filter is clean and the smell persists, call a technician. Otherwise the problem will fester, endangering much more expensive components.

Periodic cleaning by Premier HVAC technicians will keep your system running smoothly year-round. We serve Manhattan, Queens, Brooklyn and Long Island.