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149
Message
System characteristics Cause
Measures
D3 Low pressure
Low pressure fault
■ Heat pump faulty
■ Fan faulty or air ducts
blocked
■ Low pressure sensor
faulty
■ Have heat pump tested
by a refrigeration engi-
neer.
■ Check fan and shut-off
facilities; clean air ducts
if required.
Check low pressure sen-
sor, lead and EEV control-
ler. If required, check
whether jumper in plug
aYH
between terminal 3
and 4 is fitted (switching
signal can be tested at ter-
minal 1X5.7 (230 V) and
must be continuously
active if a pressure sensor
is installed).
Troubleshooting
Control unit diagnostics
(cont.)
5414 828 GB
Service
Summary of Contents for VITOCAL 350-A
Page 54: ...54 5 3x 7 6 3x 3x 3x Installation sequence Fitting the outer panels cont 5414 828 GB ...
Page 58: ...58 2x 10 11 3x 3x Installation sequence Fitting the outer panels cont 5414 828 GB ...
Page 62: ...62 Type AWH I 1 Installation sequence Installing the heat pump cont 5414 828 GB ...
Page 228: ...228 052 054 059 008 056 025 020 Parts lists Parts list type AWH I cont 5414 828 GB ...
Page 236: ...236 053 032 039 034 038 033 034 039 027 Parts lists Parts list type AWH O cont 5414 828 GB ...
Page 237: ...237 052 054 059 008 055 025 020 Parts lists Parts list type AWH O cont 5414 828 GB Service ...