1) "My central air conditioning system is running but not cooling"
Several things could be responsible for this occurring and a few things that you can check before placing a service call. Has your filter been cleaned or replaced recently? I dirty filter will prohibit air flow through your system causing it to not cool properly and even ice up. It is important for you to change or clean your filter prior to the air conditioning season as well as checking it at least twice during the season. Your system could also be low on Freon which needs to be checked by a certified technician

2) "My gas furnace isn't heating"
Most likely your ignitor has failed and needs to be replaced by a certified technician. Is your filter door properly installed? When you clean or change your filter, you must make certain that the filter door is properly put back. There is a safety switch on the filter door that will shut the furnace off when removed. You must properly put it back on in order to trigger the switch. There is also switch located on the side of the furnace that must be in the on position at all times. Check your vent pipes that are normally located in the exterior of your home. Make sure that these pipes are free and clear of any debris and/or snow. If anything gets in these vent pipes, this will not allow the furnace to come on. Please do not cover these pipes with screens or anything else.

3) "There is water on the floor under my unit"
This is typically a faulty condensate pump, a clogged drain line or possibly a frozen indoor coil. You will need a certified technician to take care of this problem.

4) "My thermostat is blank"
A blank thermostat usually means that there is no power to your system. Have you checked your breakers? If so, you could have a faulty thermostat.

5) "My system continually runs and won't shut off"
Most times this means you have a faulty or stuck relay switch or contactor. You will need a certified technician to check this problem.

6) "My outdoor heat pump unit has ice on it"
1st thing you should do is switch your thermostat over to Emergency Heat. This will bypass the outdoor unit and produce heat strictly from the indoor unit. There could be several reasons for this. Your system could be low on charge, the defrost board could have failed or your indoor air filter could be dirty.

7) Make sure your high/low returns are in the right position for the right season.
Heating months the top return should be shut and the bottom return should be open. This should be reversed in the cooling months.