Daitsu FDLA-09, Installation, Operation & Service Manual

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Control Logic For 2 ‐ Pipe System D.4.
With Valve Configuration D.4.1.
COOL MODE
a) MTV2, AUX1 and electric heater are always off.
b) If Tr ≥ Ts + 1ºC (or + 4ºC if economy contact is activated), then cool operation is activated and MTV1 and AUX2 are
turned on. Indoor fan runs at set speed.
c) If Tr < Ts, then cool operation is terminated and MTV1 and AUX2 are turned off. Indoor fan runs at set speed.
d) The range of Ts is 16 ‐ 30ºC
e) Indoor fan speed can be adjusted to low, medium, high and auto.
f) When turned on, MTV1 requires 30 seconds before it is fully open.
g) When turned off, MTV1 requires 120 seconds before it is fully closed.
h) When the unit is turned off, the indoor fan will shut down after 5 seconds.
LOW TEMPERATURE PROTECTION OF INDOOR COIL
a) If Ti1 ≤ 2 ºC for 2 minutes, then MTV1 and AUX2 are turned off. If indoor fan is set for low speed, then it will
run at medium speed. If it is set at medium or high speed, then it will keep running at the same speed.
b) If Ti1 ≥ 5ºC for 2 minutes, then MTV1 and AUX2 are turned on. Indoor fan runs at set speed.
FAN MODE
a) Indoor fan runs at the set speed while heater, MTV1, MTV2, AUX1 and AUX2 are turned off.
b) Indoor fan speed can be adjusted to low, medium and high.
HEAT MODE
Heat mode without electrical heater
a) MTV2, AUX2 and electric heater are always off.
b) If Tr ≤ Ts ‐ 1 ºC (or ‐ 4ºC if economy contact is activated), then heat operation is activated and MTV1 and AUX1 are
turned on. Indoor fan runs at the set speed.
c) If Tr > Ts, then heat operation is terminated and MTV1 and AUX1 are turned off. Indoor fan repeatedly runs at low
fan speed for 30 seconds and then stops for 3 minutes.
d) The range of Ts is 16 ‐ 30ºC.
e) Indoor fan speed can be adjusted to low, medium, high and auto.
f) When turned on, MTV1 requires 30 seconds before it is fully open.
g) When turned off, MTV1 requires 120 seconds before it is fully closed.
Heat mode with electrical heater as booster
a) MTV2 and AUX2 are always off.
b) If Tr ≤ Ts ‐ 1ºC (or ‐ 4ºC if economy contact is activated), then heat operation is activated and MTV1 and AUX1 are
turned on. Indoor fan runs at the set speed.
c) If Tr > Ts, then heat operation is terminated and MTV1 and AUX1 are turned off. Indoor fan repeatedly runs at low
fan speed for 30 seconds and then stops for 3 minutes.
d) If Ti1 < 40ºC, then the electrical heater is turned on. If 40ºC ≤ Ti1 < 45ºC, then the electrical heater maintains its
original state. If Ti1 ≥ 45ºC, then the electrical heater is turned off.
e) The range of Ts is 16 ‐ 30ºC
f) Indoor fan speed can be adjusted to low, medium, high and auto.
g) When turned on, MTV1 requires 30 seconds before it is fully open.
h) When turned off, MTV1 requires 120 seconds before it is fully closed.