Mitsubishi Electric PAC-IF051B-E Installation Manual page 55

. Troubleshooting
No. Fault symptom
27 The hydrobox that The hydrobox is designed to run in an operation
mode with a higher priority (i.e. DHW mode in this
was running in the
case) at power recovery.
heating mode before
power failure is
running in the DHW
mode after power
recovery.
28 Cooling mode is NOT Dip SW2-4 is OFF.
available.
29 The cooling system 1. When the water in the circulation circuit is un-
duly hot, Cooling mode starts with a delay for
does not cool down to
the protection of the outdoor unit.
the set temperature.
2. When the outdoor temperature is lower than
the preset temperature below which the
freeze stat. function is activated, Cooling
mode does not start running.
30 The electric heaters The setting time period of Heat-pump-only
operation is short.
are activated shortly
after DHW or LP
mode starts running
after Cooling mode.
31 During DHW or LP If the preset temperature below which the freeze
stat. function is activated is low, error L6 is more
mode following the
likely to occur interruption operation before the
cooling mode, error
freeze stat. function is activated.
L6 (circulation water
freeze protection)
occurs and operation
stops frequently.
Possible cause
• Normal operation.
• After the DHW max. operation time has elapsed or the DHW max. temperature has
Turn Dip SW2-4 to ON. (Refer to "5.1 Dip Switch Functions" in this manual.)
1.
2.
Adjust the setting time period of Heat-pump only operation. (Refer to "<Electric heater
(DHW)> on Page 47.
Adjust the preset temperature below which the freeze stat. function is activated. (Refer
to "<Freeze stat function>" on Page 49.
Explanation - Solution
been reached, the DHW mode switches to the other mode (ex. Heating mode).
Normal operation.
To run Cooling mode overriding the freeze stat. function, adjust the preset tem-
perature below which the freeze stat. function is activated. (Refer to "<Freeze stat
function>" on Page 49.
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