Malfunctions; Causes; Switching - Johnson Controls York YKN2Open board Technical Information

5.1 Malfunctions

There are two different types of malfunction. Incidents do not cause the unit to stop and faults or
lockouts cause the unit to stop.

5.2 Causes

5.2.1 Switching

N O T E
[See the operating parameters in the section Rooms, see on page 25].
Indoor fan thermal switch
Activation of this causes the stoppage of the entire unit and a fault in the indoor fan thermal switch is
signalled.
High-pressure switch (either the outdoor fan thermal switch or compressor thermal switch)
Activation of this causes the compressor and the outdoor fan to stop. A high-pressure switch fault is
signalled.
In units with a crossed coil, outdoor fan number 2 must start up (on the electrical box side). In the event
that two fans must start up, both start up even if one has the high-pressure switch activated.
A fault is not caused if it starts during defrost, even if this is considered completed and the fault is inhibited
for 30 seconds (PHITIINH).
Low-pressure switch
Activation of this causes the compressor and the outdoor fan to stop. A low-pressure switch fault is
signalled.
When the compressor starts, the pressure switch is inhibited for 2 minutes (PLOTIINH). Its activation is
not taken into account when a defrost is being carried out. 30 seconds are timed before the fault is
signalled upon the completion of the defrost.
Electrical heating thermal switch (accessory)
Activation of this causes the electrical heating to stop and an incident to be signalled. If the error is
produced more than 3 times in one hour (RESNOTERMIC):
1. A fault is signalled in the electric resistor thermal switch.
2. The electric resistor is inhibited and switched off.
3. The Lockout relay is activated.
4. This is added to the fault history.
Gas fault (accessory)
Activation of this causes the gas heating to stop and a fault to be signalled. It is not permitted to start up
the gas heating again until the signal disappears.
The number of alarm resets on start-up is limited to 5 times.
Fault in the economiser, return fan and air quality sensor
If the air quality sensor signal is activated, a demand incident in the air quality is indicated.
If the enthalpy probes are active (jumper in S2) and there is a fault in one of the probes, as we work
between the two probes, a switch must be made to the conventional working mode and the incident must
be signalled.
If there is a fault in the return probe, the incident is signalled.
Hot water coil (accessory)
In the event that non-favourable conditions are detected, the incident is signalled and, when conditions
are favourable, the incident is deleted.
Malfunctions 5
Malfunctions 5.1
19