2U20EH2VHA User Manual

Loading ...

INTRODUCTION

A-6

ENGLISH

Functions and Control

Auto Mode

When the running mode is turned to auto after starting the

system, the system will rst determine the running mode

according to the current room temperature and then will

run according to the determined mode: Tr means room

temperature; Ts means temperature setting; Tp means

temperature of indoor coil pipe

Tr≥73°F Choose Cooling Mode

Tr<73°F Choose Heating Mode

After turning to the auto mode, the running mode will be

switched between cooling mode, fan mode, and heating mode

according to the change of the indoor ambient temperature.

There is a 15 minute delay between mode changes.

Cooling Operation Mode

Temperature control range: 60°F---86°F

Temperature dierence: ±2°F

• Control features: When Tr (input airow)>Ts (set

temperature) °F, the indoor fan will operate at the set speed,

the mode signal will be sent to the outdoor system, and

the compressor will start. When Tr (input airow)< Ts (set

temperature)°F, the indoor fan will operate at the set speed,

and the mode signal will be sent to the outdoor system, and

the compressor will stop. The system will keep the original

status if Tr= Ts.

Airow speed control: (temperature dierence ±2°F)

Automatic:

When Tr≤Ts +4°F high speed.

When Ts+2°F≤Tr<Ts+5°F, medium speed

When Tr<Ts+2°F, low speed

When the sensor is o, low speed

When the airow speed has no delay from the high to low

switching, the speed should be delayed for 3 minutes (remain

at high speed for 3 minutes.) before the next switch.

When the system is operating, you can set the high, medium

or low speed manually. (When the sensor is on or o, the

system will change the speed 2 seconds after receiving the

signal.)

• Louver control: the location for the louver can be set

according to your needs.

• Defrosting function: preventing the frosting on the indoor

heat exchanger (when cooling or dehumidifying). When

the compressor works continuously for 1 to 6 minutes

(adaptable in EEPROM) and the temperature of the indoor

coils has been below 32°F for 10 seconds, the compressor

will be stopped and the malfunction will be recorded in the

malfunction list. The indoor system will continue to run.

When the temperature of the indoor coil is raised to 45°F,

the compressor will be restarted again (the requirement of 3

minutes’ delay should be satised.)

Dry Mode (Dehumidifying Mode)

• Temperature control range: 60-86°F

• Temperature dierence: ±2°F

Control feature: Send the dehumidifying signal to the outdoor

system.

When Tr>Ts+4°F, the compressor will be turned on, the indoor

fan will operate at the set speed. When Tr is between the

Ts and Ts+4°F, the outdoor system will operate at the high

dehumidifying frequency for 10 minutes and then at the low

dehumidifying mode for six minutes. The indoor fan will

operate at low speed.

When Tr< Ts, the outdoor system will be stopped, the indoor

fan will be stopped for 3 minutes and then turned to the low

speed option.

All the frequency conversions have a ±2°F dierence.

• Wind speed control: Automatic:

When Tr≥ Ts+ 9°F, high speed.

When Ts+5°F≤Tr< Ts+9°F, medium speed.

When Ts+4°F≤Tr< Ts+5°F, low speed.

When Tr<Ts+4°F, light speed.

If the outdoor fan is stopped, the indoor fan will be paused for

3 minutes.

If the outdoor fan is stopped for more than 3 minutes and the

outdoor system still operates, the system will be changed into

light speed mode.

When the airow speed has no delay from the high to low

switching, the speed should be delayed for 3 minutes (remain

at high speed for 3 minutes) before the next switch.

When the sensor is o or Tr< Ts+5°F, the manual operation can

not be made (obligatory automatic operation).

• Louver location control: the location for the louver can be

set according to your needs.

• Defrosting function: preventing the frosting on the

indoor heat exchanger (when cooling or dehumidifying).

When the compressor works continuously for 16 minutes