Trane RTHC - Page 13

Menu Item Description
RTHC-SVD01B-EN 7
be clearable to 30 seconds in the Service Settings Menu. If the initial
RI Timer ever exceeds 15 minutes, an IFW diagnostic is generated,
warning the operator of a system problem that needs attention.
Any other pre-start system timers overlap with the RI Timer so as to
anticipate it's timeout and permit start of the compressor at or shortly
after RI Timer timeout. Any EXV prepositioning, for example, is run in
parallel with the last seconds of the RI Timer.
When the Restart Inhibit Timer is the overriding criteria holding the
chiller off, the UCM will display this as a mode and display the remain-
ing minutes: seconds remaining on the Restart Inhibit Timer.
Figure 2-1 Restart Inhibit Timer
20
15
10
5
0
Real Time (Minutes)
UCM Power Loss
Compressor
Running
Compressor
Running
Compressor
Running
Add Motor Heating
Constant (5 Min) with
each compressor start
Background Timer
Restart Inhibit Timer
Note different "cool down" rates
for running and stopped
Background Timer saved at Power Loss
and recoverd at power restoration
Restart Inhibit Timer
not saved at Power Loss,
Recalculated at power restoration
Recalculate after
each start: RIT=BT-8
0 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0
Compressor & Power status
Compressor Stopped
Compr.
Stopped
Earliest possible starts
per Restart Inhibit
Earliest possible start
per Restart Inhibit
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IFW Diagnostic if RI Timer rises above this level
RI TImer clamped to never exceed this level