Daikin GYEQ20AN Service Manual page 105

SiAUY361411EA
The outdoor unit follows the time chart on the right when starting up heating and cooling
operations. (Provided that the engine starts up (its speed exceeds 800 min
starter is turned ON.)
When the engine speed is 800 min
turning on/off the starter as follows: ON (10 sec) → OFF (10 sec) → ON (6 sec) → OFF (10 sec)
→ ON (6 sec). The engine startup occurs at the time of [t1].
When the engine fails to start up (i.e., fails to exceed 800 min
the unit outputs an alarm and stops at the time of [t3]. (In checker mode, the unit outputs an
alarm and stops when the engine fails to start up at the first attempt.)
When the starter system is not operating correctly (i.e., when no speed pulse is detected within
3 seconds after the starter is turned on), the unit enters into 4-minute standby mode when [t2] is
reached.
If this occurs at a third attempt within 2 hours, however, the unit outputs an alarm and stops (in
checker mode, it outputs an alarm and stops when this occurs at the first attempt).
Control and Functionality
Normal startup
Fan
Gas valve 2
Gas valve 1
Starter
Cooling water
pump
Sequence applied when the engine fails to start up or the starter system is not
operating correctly
Fan
Gas valve 2
Gas valve 1
Starter
Sequence applied when no engine speed pulse is detected
Fan
Gas valve
Starter
ON
6 sec.
ON
1 sec.
ON OFF with an engine speed
of 800min
ON
Synchronized operation with fan
-1
or lower As shown at right, one cycle is completed by
t1
ON
6 sec.
ON
1 sec.
ON
10 sec. 10 sec.
10 sec. 6 sec.
t1
ON
6 sec.
1 min.
ON
After purge
1 sec.
4 min.
3 sec.
t2
Control Overview
-1
) the first time the
-1 or more
025759-00E
-1
) at a third attempt within 2 hours,
1 min.
6 sec.
t3
025760-00E
025761-00E
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