It is never normal to see ice in the summer anywhere on a heat pump or central air conditioner. This includes the indoor unit, outdoor unit and interconnecting line-set. It is possible to ice-up the indoor coil however, if the air conditioner is running in very cold weather or if the thermostat is turned down extremely low.
We recommend never turning the thermostat below 70 degrees. If air conditioning is needed during winter months, such as for restaurants or businesses, then a "Low ambient kit" is required and can be installed by a service technician.
If you see ice on a heat pump or air conditioner in the summer there most likely is a problem. Below is a list of possible causes. Items in blue usually require a service call. Items in red however can be addressed, even fixed by the homeowner.
Bad indoor fan motor- not running/running slow
Loose, worn, or broken fan belt
Bad indoor fan relay
Clogged blower wheel
Low refrigerant charge
Restriction
Blocked capillary tube
Blocked orifice
Faulty expansion valve
Stuck compressor contactor
Faulty thermostat
Extremely dirty or damaged indoor coil
Clogged or blocked air filter
Supply and/or Return vents closed
Running air conditioner with windows open
Setting thermostat too low
The bottom causes in red are common problems and can be addressed by the homeowner.
One other thing to keep in mind: If you have a central humidifier, make sure it is shut off and if it has a damper - close it for the summer.
Hope this helps, remember - these are just rough guidelines and not all possible situations are covered.
Hannabery HVAC is registered with the Commonwealth of Pennsylvania's Office of Attorney General: PA#8215
