Indoor coil (also Comfort™ Coil or evaporator coil)

Home / Indoor coil (also Comfort™ Coil or evaporator coil)

Part of an indoor air unit, it functions with the air conditioner or heat pump outdoors to cool and condition indoor
air that flows over it by drawing out heat and moisture.

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TROUBLESHOOTER

LET’S TROUBLESHOOT

What type of problem are you having?

Air Conditioning Heating

Air Conditioning

Please select one

My A/C unit isn’t cooling My A/C unit isn’t running My thermostat screen is blank My house is muggy & sticky inside even with the air on My outdoor unit is making a noise

This may be caused by your thermostat settings:

Solution

Be sure your thermostat is turned ON
Be sure the thermostat is set to “Cool Mode” and the Fan is set to “Auto”.
Be sure the thermostat set point is “at least” set to 3 degrees LOWER than the displayed room temperature.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Your air filter(s) may be dirty

Solution

Check ALL A/C filters for cleanliness. Clean and/or replace (depending on filter type) if visibly dirty. ** All supply vents and return grills should be open and unrestricted for proper system air flow and cooling effect**

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Is the indoor fan running and air blowing out of your vents?

Yes No

**Your unit may be equipped with a safety float switch that is connected to the condensate drain at your indoor unit. The safety switch could be wired to shut down the outside unit ONLY to prevent further condensate backup and flooding.**

Solution

Check for a clogged condensate drain and clear if it appears clogged or there is evidence of water on the floor at the indoor unit or standing water is present inside the condensate pipe. NEVER use any chemicals including but not limited to bleach, vinegar, Drain-O inside your condensate drain. The use of anything OTHER THAN HOT water will cause eventual coil rupture and refrigerant leaks.
The use of a Wet Vac is preferable for homeowner fixes of a clogged drain.
Give your air conditioner a couple of minutes and see if it cycles on.

***NOTE--- Your unit most likely has a built in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Sounds like you need expert care.

Please turn off your system and schedule an appointment.

Schedule for Maintenance

Routine Maintenance of your air conditioner is indicated by the presence of a clogged drain.

Schedule for Maintenance

There may be a problem with the electrical service or system components. Your AC’s circuit breaker may have tripped:

Solution

Find your breaker box and look for the circuit(s) labeled AC/Furnace/Air Handler
Try flipping those circuits to “off” and then “on” for all accessible fuses and breakers labeled for the AC/Furnace/Air Handler
Give your air conditioner a couple of minutes and see if it cycles on

***NOTE--- Your unit most likely has a built in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Sounds like you need expert care.

Please turn off your system and get professional help.Breakers and fuses do NOT flip and blow without cause. A service call is indicated to evaluate further.

Schedule for Maintenance

Sounds like you need expert care.

Please turn off your system and schedule an appointment.

Schedule for Maintenance

There may be a problem with the electrical service or system components. Your AC’s circuit breaker may have tripped:

Solution

Find your breaker box and look for the circuit(s) labeled AC/Furnace/Air Handler
Try flipping those circuits to “off” and then “on” for all accessible fuses and breakers labeled for the AC/Furnace/Air Handler
Give your air conditioner a couple of minutes and see if it cycles on

***NOTE--- Your unit most likely has a built in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Sounds like you need expert care.

Please turn off your system and get professional help. Breakers and fuses do NOT flip and blow without cause. A service call is indicated to evaluate further.

Schedule for Maintenance

Sounds like you need expert care.

Please turn off your system and schedule an appointment.

Schedule for Maintenance

Solution

Be sure your thermostat is turned ON
If your thermostat uses batteries, check and replace with new batteries as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

**Your unit may be equipped with a safety float switch that is connected to the condensate drain at your indoor unit. The safety switch could be wired to shutdown the system and your thermostat to prevent further condensate backup and flooding. Often the safety switches are wired to cause a BLANK thermostat to alert the homeowner of a potential drain issue**

Solution

Check for a clogged condensate drain and clear if it appears clogged or there is evidence of water on the floor at the indoor unit or standing water is present inside the condensate pipe. NEVER use any chemicals including but not limited to bleach, vinegar, Drain-O inside your condensate drain. The use of anything OTHER THAN hot water will cause eventual coil rupture and refrigerant leaks.
The use of a Wet Vac is preferable for homeowner fixes of a clogged drain.
Give your air conditioner a couple of minutes and see if it cycles on.

***NOTE--- Your unit most likely has a built in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Sounds like you need expert care.

Routine Maintenance of your air conditioner is indicated by the presence of a clogged drain.

Schedule for Maintenance

Sounds like you need expert care.

Please turn off your system and get professional help.

Schedule for Maintenance

This may be caused by your thermostat settings:

Fans set in the fan setting of “ON” will introduce moist, humid outdoor air into the home. Changing the Fan setting to “Auto” often will eliminate this problem.

Solution

Check your thermostat settings.
Be sure the Fan Setting is NOT in the ON position.
Set the Fan Setting to the AUTO position.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please turn off your system and get professional help.

Schedule for Maintenance

Often reptiles, rodents and the like will make their way into your system. When that occurs, you might notice an associated noise from contact with motor’s fan blades.

Solution

Turn your system OFF
Check your outdoor unit for the presence of snakes, lizards, rodents.
If present, safely remove prior to further operation.
Do not attempt to open the outside unit’s cabinet yourself.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please turn off your system and get professional help.

Schedule for Maintenance

Heating

What type of heat do you have?

Gas Furnace Heat Pump Electric Heat

What type of heating problem are you having?

My heater isn’t working My thermostat screen is BLANK My heater is producing a strange smell

This can be caused by your thermostat

Solution

If your home uses a Summer/Winter switch, be sure the switch is switched to the Winter position.
Be sure your thermostat is turned ON.
Be sure the thermostat is set to the HEAT setting.
Set the thermostat set point to at least 3 degrees ABOVE the thermostat’s displayed room temperature.
Be sure the FAN setting is in the AUTO position.

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

This can be caused by lack of proper gas flow or unlit pilot light.

Solution

Be sure the gas valve to your gas furnace is fully open.
If your gas furnace uses a pilot light, be sure the pilot light is lit.
Follow the manufacturer’s recommendations for lighting the pilot light.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Your air filter(s) may be dirty.

Solution

Check ALL A/C- furnace filters for cleanliness. Clean and/or replace (depending on filter type) if visibly dirty.

** All supply vents and return grills should be open and unrestricted for proper system air flow and cooling effect**

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Is the indoor fan running and air blowing out of your vents?

Yes No

Sounds like you need expert care.

Please turn off your system and schedule an repair appointment.

Schedule for Maintenance

There may be a problem with the electrical service or system components. Your furnace’s circuit breaker may have tripped:

Solution

Find your breaker box and look for the circuit(s) labeled AC/Furnace/Air Handler
Try flipping those circuits to “off” and then “on” for all accessible fuses and breakers labeled for the AC/Furnace/Air Handler
Give your air conditioner a couple of minutes and see if it cycles on

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please turn off your system and schedule an repair appointment.

Schedule for Maintenance

Solution

Be sure your thermostat is turned ON
If your thermostat uses batteries, check and replace with new batteries as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please turn off your system and schedule an repair appointment.

Schedule for Maintenance

Smells from your gas furnace should ALWAYS be evaluated by a licensed professional. Whether the smell you are experiencing is that of an electrical or metallic nature or the rotten egg smell that is injected into the gas lines (by the gas company) to alert technicians and homeowners of a potential gas leak. None of these should be taken lightly or ignored.

Solution

Turn the gas furnace OFF.
Close the gas valve to the gas line.
Leave your home and call the gas company for service.
DO NOT OPERATE SYSTEM UNTIL CLEARED BY A LICENSED PROFESSIONAL

Schedule an appointment for repair IMMEDIATELY.

Schedule for Maintenance

What type of problem are you having?

My heater isn’t working My thermostat screen is BLANK My heater is producing a strange smell My outside unit is smoking or has steam coming from it

This can be caused by your thermostat:

Solution

Be sure your thermostat is turned ON.
Be sure the thermostat is set to the HEAT setting.
Set the thermostat set point to at least 3 degrees ABOVE the thermostat’s displayed room temperature.
Be sure the FAN setting is in the AUTO position.

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Your air filter(s) may be dirty.

Solution

Check ALL A/C- furnace filters for cleanliness. Clean and/or replace (depending on filter type) if visibly dirty.

** All supply vents and return grills should be open and unrestricted for proper system air flow and cooling effect**

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Is the indoor fan running and air blowing out of your vents?

Yes No

Sounds like you need expert care.

Please schedule a repair appointment

Schedule for Maintenance

There may be a problem with the electrical service or system components. Your furnace’s circuit breaker may have tripped:

Solution

Find your breaker box and look for the circuit(s) labeled AC/Furnace/Air Handler
Try flipping those circuits to “off” and then “on” for all accessible fuses and breakers labeled for the AC/Furnace/Air Handler
Give your air conditioner a couple of minutes and see if it comes on

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

** Should your heat pump system have Supplemental Emergency heat installed, you can change your thermostat setting from Heat to AUX/Emergency Heat for temporary heating until service is available.**

Please schedule a repair appointment

Schedule for Maintenance

Solution

Be sure your thermostat is turned ON
If your thermostat uses batteries, check and replace with new batteries as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please schedule a repair appointment

Schedule for Maintenance

If you are just turning your heat on for the first time this winter, it is not unusual, and in fact, is quite common for you to experience a dusty, burning smell. Most chances are that your furnace is actually burning away that old dust, debris and buildup that is present on your heat pump’s emergency backup electric heat strips. This is very normal. However, should the smell continue or you feel alarmed, scheduling a repair call would be the prudent approach.

Solution

Allow the dusty burning smell to dissipate. It should clear within an hour or so, depending upon amount of buildup present.
Be sure the A/C- furnace filter is clean and/or replaced as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please schedule a repair appointment

Schedule for Maintenance

This is due to your system operating in the “Defrost Mode”: This happens during the heating season and is actually normal operation of the system. Outdoor condensing coils will tend to have a buildup of ice occur during low outside (ambient) temperatures. This occurs especially during moist conditions. This buildup will cause a unit to loose efficiency by blocking air flow. The system will regularly place itself in “defrost mode” to clear its coil and improve efficiency and airflow.

Solution

Continue normal operation.
Do not be alarmed should you experience a short burst of cooler air flowing from the air vents. It is actually the air conditioner functioning in the cool setting. The system will activate the supplemental heat to offset this cooling effect during the defrost cycle. The heating cycle will return to normal heating operation when the defrost cycle terminates.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please schedule a repair appointment

Schedule for Maintenance

What type of problem are you having?

My heater isn’t working My thermostat screen is BLANK My heater is producing a strange smell

This can be caused by your thermostat:

Solution

Be sure your thermostat is turned ON.
Be sure the thermostat is set to the HEAT setting.
Set the thermostat set point to at least 3 degrees ABOVE the thermostat’s displayed room temperature.
Be sure the FAN setting is in the AUTO position.

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up***DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Your air filter(s) may be dirty.

Solution

Check ALL A/C- furnace filters for cleanliness. Clean and/or replace (depending on filter type) if visibly dirty.

** All supply vents and return grills should be open and unrestricted for proper system air flow and cooling effect**

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Your air filter(s) may be dirty.

Solution

Check ALL A/C- furnace filters for cleanliness. Clean and/or replace (depending on filter type) if visibly dirty.

** All supply vents and return grills should be open and unrestricted for proper system air flow and cooling effect**

Did that solve your problem?

Yes No

Sounds like you need expert care.

Please schedule a repair appointment

Schedule for Maintenance

There may be a problem with the electrical service or system components. Your furnace’s circuit breaker may have tripped:

Solution

Find your breaker box and look for the circuit(s) labeled AC/Furnace/Air Handler
Try flipping those circuits to “off” and then “on” for all accessible fuses and breakers labeled for the AC/Furnace/Air Handle
Give your air conditioner a couple of minutes and see if it cycles on

***NOTE--- Your unit most likely has a built-in time delay. You MUST allow 10 minutes for the time delay to reset and the system to start-up*** DO NOT keep adjusting the thermostat during this time.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Please turn off your system and schedule an repair appointment.

Schedule for Maintenance

Solution

Be sure your thermostat is turned ON
If your thermostat uses batteries, check and replace with new batteries as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Schedule for Maintenance

Solution

Allow the dusty burning smell to dissipate. It should clear within an hour or so, depending upon amount of buildup present.
Be sure the A/C- furnace filter is clean and/or replaced as indicated.

Did that solve your problem?

Yes No

Awesome!!

Glad we were able to help you solve your problem. We’ll be here. If you should need us again. Don’t forget to BOOKMARK our site for any future needs.

Sounds like you need expert care.

Schedule for Maintenance

We Service all makes and models

Indoor coil (also Comfort™ Coil or evaporator coil)

TROUBLESHOOTER

LET’S TROUBLESHOOT

This may be caused by your thermostat settings:

Solution

Awesome!!

Your air filter(s) may be dirty

Solution

Awesome!!

Solution

Sounds like you need expert care.

Solution

Sounds like you need expert care.

Sounds like you need expert care.

Solution

Sounds like you need expert care.

Sounds like you need expert care.

Solution

Awesome!!

Solution

Sounds like you need expert care.

Sounds like you need expert care.

This may be caused by your thermostat settings:

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

This can be caused by your thermostat

Solution

Awesome!!

This can be caused by lack of proper gas flow or unlit pilot light.

Solution

Awesome!!

Your air filter(s) may be dirty.

Solution

Awesome!!

Sounds like you need expert care.

There may be a problem with the electrical service or system components. Your furnace’s circuit breaker may have tripped:

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

Solution

This can be caused by your thermostat:

Solution

Awesome!!

Your air filter(s) may be dirty.

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

This can be caused by your thermostat:

Solution

Awesome!!

Your air filter(s) may be dirty.

Solution

Awesome!!

Your air filter(s) may be dirty.

Solution

Sounds like you need expert care.

Solution

Awesome!!

Sounds like you need expert care.

Solution