SAN DIEGO, CALIFORNIA—Sometimes you see or hear something that makes you stop in your tracks. This was one of those things. On Pinterest, a popular online pinboard that allows users to organize and share images, someone had pinned a picture with a caption that described it as a “genius solution” to an ugly thermostat. This homeowner had built a frame around their thermostat and put a hinged lid with a decorative knob inside the frame to cover the control panel.

“The homeowner may have been pleased with the aesthetics, but it’s a terrible idea to cover your thermostat,” says Gabriel Carini, who has offered heating and cooling services in San Diego for more than a decade. “It won’t be able to accurately read the indoor temperature, making the system run inefficiently and compromising indoor comfort levels.”

There are other solutions to an unsightly thermostat that won’t negatively impact your HVAC system’s performance, such as upgrading to a new smart thermostat with a minimalist look like the ecobee or having an AC repair technician move your old one to a less conspicuous area. (

This got us thinking about other mistakes that homeowners may be making that are bad for their heating and cooling units. Here are four other common missteps:

1. Heating up the thermostat. Covering up a thermostat will certainly heat it up, but direct sunlight and lamps, televisions, stereos or other heat-generators that are too close can accidentally drive up the temperature reading and overwork the air conditioner.

2. Blocking air return vents. Vents are not the most attractive element of a home either, but when you try to hide them with furniture or drapes the system isn’t getting the air flow it needs to run efficiently and maintain a comfortable temperature indoors. Keep them uncovered and dust them often for a healthy HVAC unit.

3. Using a super-efficient air filter. Some people assume a higher number listed on an air filter package must mean it is better while others reach for whatever filter is least expensive. A cheap flimsy filter will result in poor indoor air quality, but a very efficient air filter can cause too much drag for the standard residential HVAC system to effectively handle, especially if it is an older system. (

“Instead of going by the price tag or the manufacturer’s marketing, check your HVAC manual for recommendations or talk to a professional,” says Carini, a heating repair expert. “The best air filter strikes a balance between airborne particulate removal and overall heating and cooling system efficiency.”

4. Closing vents and doors to unused areas. This can decrease the efficiency of a central air conditioning system and cause humidity problems.

“It’s a myth that closing off rooms that aren’t used very often will save energy,” says Carini, who founded his San Diego, CA air conditioning and heating business in 2003. “Closing registers and doors for a forced-air heating and cooling system in the typical, insulated California home will actually make the unit work harder and cost you more.”

If you’ve made one or more of these air conditioning mistakes, we can help you fix the problems and get your system running at top efficiency. Just call our office to schedule an appointment with one of our highly-trained, experienced HVAC technicians.