E93.1001EN.C Manual CD
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Display message
T 2 - T 1 h i g h
9 9 9 , 5
h r s
Reason
Difference between T2 and T1 has exceeded the blocking value
which has been set in the parameters.(return temp higher than
flow)
Cause:
The water flow through the unit is too low.
Corrective action:
Check functioning of the pump.
Check/open all valves that might restrict the water flow through the unit.
Check for an external system pump that influences flow through the unit.
Check if the system resistance exceeds the spare capacity of the unit pump.
Make sure the heat exchanger is clean. Heat exchanger fouling (partly blockage) will in-
crease the resistance causing the water flow to drop.
Display message
W a t e r p r e s s u r e
f a u l t
9 9 9 , 5
h r s
Reason
Water pressure is too low or high.
Cause:
The water pressure in the system is too high.
Corrective action:
Check if the system pressure is too high after (re)filling.
Make sure that there is a pressure relief valve and expansion vessel installed in the sys-
tem, according to the applicable standards.
Check if there is an open connection between the unit and the relief valve plus expansion
vessel.
Be aware that if the unit is installed in the basement of a tall building, only the static pres-
sure of the water column above the units can raise above the maximum allowable limits.
Make sure that this is not the case.
Cause:
The water pressure in the system is too low.
Corrective action:
Check if there is no leakage in the system that causes the pressure to drop. Fix any leak-
age and fill the system.
Check if there is an external system pump that sucks water through the water heater,
causing an under pressure (bad installation design).
Display message
W A T R H T R : T 3
E x t e r n a l
> > > :
6 0 . 0 ° C ( - 3 0 . 7 ° C )
Reason:
T3 external tank sensor is not connected to the terminals.
Cause:
The sensor is not connected to the terminal, or the wire is broken. The sensor is malfunc-
tioning.
Corrective Action:
Connect the sensor to the terminals 3 and 4.
Check the wires from the sensor to the terminals.
Check the sensor on resistance 10K at 25°C.
