ES AWH11-V5+, User Manual

Page: 67 / 86

3. Usage
67
Unit working st atue Failure Code Type
Failure
Possible Reasons And Solutions
00 Pb
System 1 Water outlet Temp.
too low protection in
defrosting
Compressor of system
1 quit defrosting and
switch back to
heating/DHW
operation
When unit is working in defrosting, if water outlet
temperature is too low, water may freezing up in
plate heat exchanger and damage the plate heat
exchanger. When this happens, unit quit defrosting
and switch back to heating/DHW operation. It may
cause quite thick ice on evaporator coil. Please set
the set temperature for heating/DHW higher, or turn
ON the back-up heating system so actual water
temperature is high enough for defrosting operation.
If water volume in the system is too small that cause
the water temperature drops too much in defrosting
operation, please add a buffer tank that matches the
unit capacity to the system. Please check whether
indoor coil temperature sensor and water outlet
temperature sensor is mixed, so the reading of outlet
water temperature drops dramatically during
defrosting operation.
00 Pc
00 Pd
Water system anti-freezing
protection stage 1
Circulation pump
circulates for 1 minute
in every 6 minutes
When unit is turned OFF, if ambient temperature
and water temperature is low, water system has the
risk of freezing up. Thus it is necessary to havethe
circulation pump starts to circulate the water in the
system, for anti-freezing purpose.
Water system anti-freezing
protection stage 2
Compressor starts
automatically.
When unit is turned OFF, if ambient temperature
and water temperature is too low, unit will start to
work automatically to heat the water up to a
minimum safe level. This is a minimum protection
for protecting to help preventing the water system
from freezing up. Other soltuions must be added
according to local regulations to ensure the safety
of water system.
Unit working st atue Failure Code Type
03 P3
Wired communication
protection
Possible Reasons And Solutions
Failure for Wired Controller
Failure
If a external control
unit is connected have
communication, unit
keeps on working; if
no external control
unit is connected, unit
stops.
Communication data lost too much. Check whether
communication cable is correctly connected; check
whether communication cable is longer than 30M;
whether there has a source of the disturbance nearby
the unit. Check whether the dip-switch DIP2-2 is set
to ON, which system has a external master control
unit and doesn't need a operation panel. If yes, set it
back to OFF. Check and replace the indoor PCB if
necessary. Unit recovers when communication
recovers.
Indoor Unit Failure Codes