7.
OUTLINE OF CONTROL CIRCUIT
97
NO.
ITEM
OUTLINE OF SPECIFICATION
REMARKS
7
Test operation
8
High pressure release
To enable system testing it is possible to force cool or
heat irrespective of room temperature.
To enable this function, select required system mode
using the [MODE] button. Then turn on the remote
controller by holding the [ON/OFF] button continuously
for 5 seconds. The unit will enter test run mode with the
indoor fan on [HIGH].
The following control is performed when high-pressure
switch of the Outdoor Unit is actuated.
1- In cooling operation
Compressor is turned off and if the high pressure
switch does not reset within 5 seconds, it is judged
abnormal.
2- In heating operation
Compressor is turned off and if the pressure switch
does not reset within 30 seconds, it is judged
abnormal. If the switch resets within 30 sec., the
compressor restarts 2 minutes and 20 sec later and
operates according to the diagram below.
3- In defrosting operation
Compressor is turned off, the defrost operation is
cancelled and returns back to heating operation.
<Outdoor Unit
control>
LED lamp comes on
in abnormal
condition, with
abnormal code
transmitted to Indoor
Unit.
9
Protection if Mg SW is
thought to be fused.
If the high pressure SW continues to operate for 5
seconds after the compressor has stopped, fusing of Mg-
SW is detected and the outdoor fan is controlled as de
scribed below.
1- When the four-way valve is OFF (including during
defrosting operation) Turn ON the outdoor fan at
maximum.
2- When the four-way valve is ON Turn OFF the
outdoor fan. (When the compressor has stopped, the
outdoor fan should be OFF).
10
Defrosting
<Outdoor Unit
control>
1- In heating operation,
defrosting is made based
on outdoor heat exchange
temperature Te,
2- When cumulative working
time of compressor is [A]
zone has amounted to 55
minutes, defrosting
operation starts, (25
minutes initially)
3- The longest defrosting time is 12 minutes. 60 seconds
in the case of turning into [B] zone, and immediately
returning back to heating mode when [C] zone is
reached.
11
Four-way valve reversal
control
The following control shall be performed when the
compressor stops:
1- The 4-way valve in the hold state shall be reserved 10
seconds before the restart delay timer counts the
maximum count (2 minutes 20 seconds).
2- After the restart delay timer counts the maximum
value, the specified mode shall be selected.
ON
OFF
30 sec.
2 mins and
20 sec.
120 sec.
Fan OFF
Compressor
Outdoor fan speed
12
8
C
B
A
-3
(
°
C)
Outdoor Coil (Te)
Heronhill - for all your Toshiba requirements
Tel: 01823 665660
www.heronhill.co.uk
Fax: 01823 665807