York EVHC 09 DSAAAR, Service Manual

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145
ĸ
Protection
Protection is the same as that under the cooling mode.
(3) Heating Mode
ķ
Working conditions and process of heating
If T
amb
.
≤
T
preset
+2
ć
, the unit enters heating mode, in which case the four-way valve, the compressor and the outdoor fan
will operate simultaneously, and the indoor fan will run at preset speed in the condition of preset cold air prevention.
If T
amb.
≥
T
preset
+5
ć
, the compressor will stop, the outdoor fan will stop with a time lag of 30s, and the indoor fan will stop
after 60-second blow at low speed
If T
preset
+2
ć
<T
amb.
< T
preset
+5
ć
, the unit will maintain its original operating status.
Ø
Under this mode, the four-way valve is energized and temperature can be set within a range of 16 - 30
ć
. The
operating symbol, the heating symbol and preset temperature are revealed on the display.
ĸ
Condition and process of defrost
When duration of successive heating operation is more than 45 minutes, or accumulated heating time more than 90 minutes,
and one of the following conditions is reached, the unit will enter the defrost mode after 3 minutes.
a.
T
outdoor amb.
≥
A
ć
, T
outdoor tube
≤
W
ć
;
b. A
ć
≤
T
outdoor amb.
<B
ć
, T
outdoor tube
≤
X
ć
;
c. B
ć
≤
T
outdoor amb.
<C
ć
, T
outdoor tube
≤
Y
ć
;
d. T
outer amb.
<C
ć
, T
outer tube
≤
Z
ć
At that time, the indoor fan stops and the compressor stops, and after 30 seconds the outer fan will stop, and then after 30
seconds, the four-way valve will stop. After 30 seconds, the compressor is initiated for raising the frequency to defrost
frequency.
When the compressor has operated under defrost mode for 7.5 minutes, or T
outer tube
≥
E
ć
, the compressor will be converted
to 53Hz operation. After 30 seconds, the compressor will stop. And after another 30 seconds, the four-way valve will be
opened, and after 60 seconds, the compressor and the outer fan will be started, the indoor fan will run under preset cold air
prevention conditions, and H1 will be displayed at temperature display area on the display panel. Defrost frequency is
70Hz.
3.Protection
u
Cold air prevention
The unit is started under heating mode (the compressor is ON):
ķ
In the case of T
indoor amb.
<24
ć
: if T
tube
≤
40
ć
and the indoor fan is at stop state, the indoor fan will begin to run at low
speed with a time lag of 2 minutes. Within 2 minutes, if T
tube
η
40
ć
, the indoor fan also will run at low speed; and after
1-minute operation at low speed, the indoor fan will be converted to operation at preset speed. Within 1-minute low speed
operation or 2-minute non-operation, if T
tube
η
42
ć
, the fan will run at present speed.
ĸ
In the case of T
indoor amb.
≥
24
ć
: if T
tube
≤
42
ć
, the indoor fan will run at low speed, and after one minute, the indoor fan
will be converted to preset speed. Within one-minute low speed operation, if T
tube
η
42
ć
, the indoor fan will be converted
to preset speed.
Note: T
indoor amb.
indicated in
○
1 and
○
2 refers to, under initially heating mode, the indoor ambient temperature before the
command to start the compressor is performed according to the program, or after the unit is withdrawn from defrost, the
indoor ambient temperature before the defrost symbol is cleared.
u
Total current up and frequency down protection
If the total current I
total
≤
W, frequency rise will be allowed; if I
total
≥
X, frequency rise will not be allowed; if I
total
≥
Y, the
compressor will run at reduced frequency; and if I
total
≥
Z, the compressor will stop and the outdoor fan will stop with a time
lag of 30s.
(4) Fan Mode
Under the mode, the indoor fan will run at preset speed and the compressor, the outdoor fan, the four-way valve and the
electric heater will stop.
Ø
Under the mode, temperature can be set within a range of 16 - 30
ć
.
(5) AUTO Mode
ķ
Working conditions and process of AUTO mode
Under AUTO mode, standard cooling temperature T
preset
is 25
ć
and standard heating temperature T
preset
is 18
ć
.
a. Once energized, if T
amb
.
≤
20
ć
, the unit will be started under heating mode; if 20
ć
< T
amb
.< 25
ć
, the unit will run
under fan mode and the run indicator will be bright; and if T
amb
.
≥
25
ć
, the unit will be started under cooling mode.
Operation