Specifications

FM774/0708 BOOK 2 4
INTRODUCTION
This document is designed as a guide only, and does not cover all possible faults that may occur. It
is intended for use by technicians and trades people with fault finding skills and relevant qualifica-
tions. Its aim is to help identify failed components and assist in diagnosis of system faults. The
guide has been set out in logical order, from the basic to the more complex faults. All faults should
be approached in this order and all instructions followed to avoid incorrect fault identification and/
or part replacement. It should be noted that all information provided in this guide is based on cur-
rent designs. Variations to these designs will be encountered on earlier models, since modifications
have occurred to the product.
ABREVIATIONS
V Volt
W Watt
CZ Coolzone
CO Comfort
MX Formerly “Maxima”
CZR Coolzone Rotary
KDU Keypad Display Unit
MCU Master Control Unit
R/U Roof Unit
cct Circuit
DVT Drain Valve Timer
PIR Passive Infra-Red (detector)
LED Light Emitting Diode
PIN Personal Identification Number
MRU Modular Roof Unit
MWL Magnetic Water Level System
MS Magnetic Sensor Water Level System