11-7
CONTROL SYSTEM
SM WNGDCI 1-E.1 GB
11.7.5
Heat Sink Over Heating Protection (NA for DCI 25 and 35)
HST Trend
HST
Decreasing
No Change
Increasing
HST
SC
SC
SC
> 90
85 < HST ≤ 90
D1
D2
D2
82 < HST ≤ 85
SR
D1
D2
80 < HST ≤ 82
SR
SR
D1
78 < HST ≤ 80
Norm
Norm
SR
HST ≤ 78
Normal
11.7.6
Outdoor Coil Deicing Protection
11.7.6.1 Deicing Starting Conditions
Deicing operation will start when either one of the following conditions exist:
Case 1: OCT OAT – 8 AND TLD
<
> DI
Case 2: OCT OAT – 12 AND TLD 30 minutes.
<
>
Case 3: OCT is Invalid AND TLD DI
>
Case 4: Unit is ust switched to STBY AND OCT
j
< OAT - 8
Case 5: NLOAD 0 AND OCT OAT -8
=
<
OCT – Outdoor Coil Temperature
OAT – Outdoor Air Temperature
TLD – Time from Last Deicing
DI – Deicing Interval (Time Interval Between Two Deicing)
Deicing interval time when compressor is first started in heat mode, is 10 minutes if OCT < -2, and
is 40 minutes in other cases.
Deicing interval time is changed (increased/ decreased in 10 minutes steps) as a function of
deicing time. If deicing time is shorter then former deicing time, the deicing interval time will be
increased. If deicing time is longer then former deicing time, the deicing interval time will be
decreased.
CONTENTS
