Access the most frequently asked questions (FAQs) on our AN air to water chillers and heat pumps. They have been designed and constructed to satisfy small and medium sized cooling and heating applications in residential or commercial applications. Don't see the answer to one of your questions? Send us an email at aermec@mitsair.com and one of our team members will be happy to assist you.
Heating Startup
To turn the unit on for the first time push the up button (*sun) and hold for 5 seconds. The sun indicator will light up. The AN unit will come on in heating and operate to the preset factory parameters.
Cooling Startup
To turn the unit on for the first time push the up button (*snowflake) and hold for 5 seconds. The snowflake indicator will light up. The AN unit will come on in cooling and operate to the factory pre-set factory parameters.
Heating Shutdown
To turn the unit off in heating mode push the up button (*sun) and hold for 5 seconds. Indicator lamp will go off. AN unit is off.
Cooling Shutdown
To turn the unit off in cooling mode push the up button (*snowflake) and hold for 5 seconds. Indicator lamp will go off. AN unit is off.
To switch from Heating to Cooling or Cooling to Heating
You must turn the operating cycle off by pushing the operating mode button (up arrow or down arrow) for 5 seconds until the unit has stopped. The unit is now in standby mode. Wait for five seconds and then press the desired mode button for 5 seconds. The unit must be put into standby manually before you can start in the opposite mode. The AN unit indicator will come within 5 minutes.
Alarm Reset
To reset an Alarm press the up and down arrow buttons simultaneously for 5 seconds. If the alarm has been manually or automatically reset the red indicator bell LED will go out. Press the clear button on the PRD1 for 5 seconds if installed.
Defrost Test
To start a defrost test you must block off the condenser coil with a plastic sheet and allow the unit to run in heating for at least 5 minutes. Then press the SEL and Up arrow buttons simultaneously for 5 second. The unit will go into defrost if are the values at the end of the defrost will be lower than the values set in the microchiller for the end of the defrost. If unit temp and press conditions permit.
Reset Parameters
Press and hold the Prg. button at the microchiller electrical power-up. When the procedure is over the display will show dF.
New User Directions for AN Units Operating with BMS Controls
Install dry contact relays and wiring to engage the AN unit ON/OFF 1A switch. Set the microchiller 2 parameters to switch from standalone to BMS operation. The closed 1A On / Off switch starts the AN circulating pump and the pump LED indicator. The flow switch closes. The microchiller 2 checks the safety controls. Compressor delay timer engages and starts countdown. The # 1 LED will start to flash indicating the compressor is going to start. If all the safeties are closed the compressor will start within 5 minutes. The compressor and associated LED indicator lights up. When the inlet water temperature reaches it set point the microchiller 2 will shut off the compressor. If the BMS is satisfied with the building conditions the microchiller control will shut down the compressor and the circulating pump.