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Airlok Heating & Cooling LLC
Airlok Heating & Cooling LLC
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  • More
    • Home Page
    • Contact Us
    • About Us
    • Services
      • AC Repair
      • AC Maintenance
      • AC Installation
      • Heating Repair
      • Heating Maintenance
      • Heating Installation
      • Emergency HVAC Service
      • Commercial HVAC Services
    • Blog
    • Maintenance Agreements
    • Indoor Air Quality
    • HVAC Discounts
    • HVAC System Checklist
    • Service Locations
      • HVAC Laurel MD
      • HVAC Columbia MD
      • HVAC Ellicott City MD
      • HVAC Elkridge MD
      • HVAC Odenton MD
      • HVAC Bowie MD
      • HVAC Crofton MD
      • HVAC Fulton MD
      • HVAC Annapolis MD
      • HVAC Glen Burnie MD
      • HVAC Pasadena MD
      • HVAC Hanover MD
      • HVAC Severn MD
      • HVAC Millersville MD
      • HVAC Pikesville MD
      • HVAC Severna Park MD
      • HVAC Clarksville MD
      • HVAC Gaithersburg MD
      • HVAC Fairland MD
      • HVAC Timonium MD
      • HVAC Randallstown MD
  • Home Page
  • Contact Us
  • About Us
  • Services
    • AC Repair
    • AC Maintenance
    • AC Installation
    • Heating Repair
    • Heating Maintenance
    • Heating Installation
    • Emergency HVAC Service
    • Commercial HVAC Services
  • Blog
  • Maintenance Agreements
  • Indoor Air Quality
  • HVAC Discounts
  • HVAC System Checklist
  • Service Locations
    • HVAC Laurel MD
    • HVAC Columbia MD
    • HVAC Ellicott City MD
    • HVAC Elkridge MD
    • HVAC Odenton MD
    • HVAC Bowie MD
    • HVAC Crofton MD
    • HVAC Fulton MD
    • HVAC Annapolis MD
    • HVAC Glen Burnie MD
    • HVAC Pasadena MD
    • HVAC Hanover MD
    • HVAC Severn MD
    • HVAC Millersville MD
    • HVAC Pikesville MD
    • HVAC Severna Park MD
    • HVAC Clarksville MD
    • HVAC Gaithersburg MD
    • HVAC Fairland MD
    • HVAC Timonium MD
    • HVAC Randallstown MD

HVAC Checklist

Electrical Breaker

Tripped Breaker

Thermostat Settings

Tripped Breaker

If your circuit breaker has tripped, you can reset it by pushing the breaker lever completely to the "OFF" position, then pushing it completely to the "ON" position. If the breaker continues to trip, please give us a call and we will be happy to come out and resolve the issue.

Electrical switch

Furnace Switch

Thermostat Settings

Tripped Breaker

When a technician comes to your home to perform a service on your HVAC system, such as a tune-up or duct cleaning, they will turn off the furnace switch. Sometimes, the technician forgets to turn the switch back on, which can leave your system without power.

Heating and cooling thermostat

Thermostat Settings

Thermostat Settings

Thermostat Settings

HVAC thermostats have become more advanced throughout the years, making them a little more complicated to understand and operate. Checking your thermostat setting is always a good idea. Making sure to check "hold temp" and programmable settings.

HVAC air filter

Dirty Air Filter

Thermostat Batteries

Thermostat Settings

A blocked air filter is one of the most common problems with heating and air conditioning systems. A blocked filter can cause a variety of problems, from overheating furnaces to frozen A/C coils. The condition of your air filter is critical for efficient HVAC operation.

HVAC thermostat batteries

Thermostat Batteries

Thermostat Batteries

Thermostat Batteries

We recommend that you install new batteries in your battery-powered thermostat once a year, or sooner if the battery icon appears on the display. This is a good place to check if your system is not working. Some thermostats have slots that allow you to replace the batteries without removing them from the wall or subbase.

Frozen air conditioning unit

Frozen Unit / Coil

Thermostat Batteries

Thermostat Batteries

If you see ice on your AC or Heat Pump system and your system isn't working properly, you should turn the system off and call us for service. Our technician will quickly diagnose the problem and provide a detailed report with recommendations.

Blinking red bulb

Diagnostic LED

Diagnostic LED

Diagnostic LED

Most gas furnaces have a small sight glass built into the bottom furnace door. A small blinking light can be seen through this sight glass and will blink a certain number of times to indicate what type of lock out the furnace is experiencing. The amount of times the LED blinks can be cross-referenced with a diagnostic chart. The fault can be reset by turning the furnace switch off, then back on.

Heat pump unit

Check Heat Pump

Diagnostic LED

Diagnostic LED

If you've confirmed that your thermostat is set for heating and turned up at least 5 degrees higher than the room temperature, it's a good idea to check that the heat pump unit outside is actually running. This is also helpful to ensure that you're getting the most efficient heating that your heat pump system has to offer.

Icy PVC pipes

Furnace Venting

Diagnostic LED

Furnace Venting

Many high efficiency gas furnaces have some type of exhaust and intake venting that goes to the outside of your home or business. Each time the heat is turned on, those pipes are pushing and pulling exhaust and air, which can pull in materials like leaves, etc. It’s a good idea to make sure there are no obstructions or potential obstructions where these pipes vent.

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  • Home Page
  • Contact Us
  • About Us
  • AC Repair
  • AC Maintenance
  • AC Installation
  • Heating Repair
  • Heating Maintenance
  • Heating Installation
  • Emergency HVAC Service
  • Commercial HVAC Services
  • Maintenance Agreements
  • Indoor Air Quality