87
[A04] Error Freeze prevention control
When the outside temperature and inlet water temperature is low (approx. 20 °C or lower) and the room load is
large (operation frequency
≥
rating), the freeze prevention control may be activated.
Excess air
inside pump
Secure water
circulation amount
Circulation
flow shortage
Dirt clogging
inside water circuit
12 M or longer
water pipe to
a branch, or 5 or
less branches
Fit buffer tank and the
second pump
Set DP_SW11-1 to ON
No
No
No
No
(inside strainer, etc)
Chattering from
flow switch
Water heat
exchanger board DP_SW11-1
is ON
Power is
connect to backup
heater terminal
Backup
heater terminal has
AC 220-230 V
(± 10 %)
Start
Operation restart
Replace water heat
exchange control board
Perform
air vent
Set heater breaker to ON
Check indoor wiring
Replace flow switch
No
No
Yes
Yes
Yes
Yes
Replace backup heater unit
No
(Backup heater NG)
Backup
heater element
is conductive
Yes
Replace TC, TWO,
and TWI sensors
No
TC, TWO, TWI
sensor characteristics
are correct
Yes
Connect backup heater
power cable
Yes
Yes
Short circuit piping
Fit buffer tank and the
second pump
Total water amount in
the system is too little,
or water piping is too
short
(Refer to Characteristic table on page 113)
AMP Air Conditioning
www.ampair.co.uk | [email protected]