• Check to see the output and return registers are open and free from obstacles like furniture.
• Make sure the emergency switch is in the “on” position.
• Check to see if any circuit breakers are off or have tripped.
• Make sure the doors to the filter or other parts of the heating system are fully closed.
• Water heating systems do not have or need filters.
• Make sure your thermostat is set to the heating mode in the winter and cooling mode in the summer.
• Check the batteries in your thermostat for corrosion in the battery compartment.
• Soot is a sign of serious problems. You should schedule a service call.

NOTE: Be patient during the summer months when it is very hot outside. You may be encountering a practical limit of cooling to about 20 degrees below the outside air temperature. Remember, if it is 95 degrees outside, the house may only be able to be cooled to 75 degrees. This may be a limitation of the air conditioning system and not necessarily a problem.