Auto Mode; Evaporator Low-Temperature Protection - Hitachi RPIL-1.0PNN1DH Service Manual

5. CONTROL LOGIC DESCRIPTION

5.4 Auto Mode

This mode can be chosen with remote controller and the setting temperature can be changed
between 61°F~86°F(16°C~30℃).
In auto mode, the unit will choose cooling, heating or fan-only mode according to ΔT (ΔT
=T1-Ts).
ΔT=T1-Ts Running mode
Cooling
ΔT＞3 7°F(3℃)
Fan-only
27°F(-3℃)≤ΔT≤37°F(3℃)
Heating
ΔT ＜27°F(-3℃)
Indoor fan will run at auto fan of the relevant mode. The louver operates same as in relevant
mode. If the compressor keeps stopping for 10 minutes or the setting temperature is modified,
the machine will choose mode according to ΔT again.

5.5 Evaporator Low-temperature Protection

DC-Inverter
AC will enter T2 protection if any of the following condition is satisfied.
Condition:
T2
On
TE6
TE5
Off
Cooling mode: When the indoor coil temp. T2 keeps lower than TE5 for 120 seconds,
the compressor and outdoor fan will shut off. When T2 is higher than TE6, the
compressor and outdoor fan will restart up.
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