Horstmann CentaurPlus C21 User Manual

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The Horstmann C21 two channel programmer gives independent control
over hot water and heating with up to 3 ON/OFF settings per 24 hours.
It also has a 1 hour manual boost button for the hot water and an advance
button for the central heating.
There is also a programming switch allowing permanent selection of:
OFF/ON/AUTO/ALL DAY.
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Horstmann CentaurPlus C21 Specifications

Power

contact rating	3 (1) Amps 230V AC
supply voltage	230V AC 50Hz

Operating Environment

operating temperature range	0°C to +40°C
pollution degree	2
battery life	10 months continuous operation (minimum)

Weight and Dimensions

dimensions	84mm x 150mm x 29mm

Summary

User Operating Instructions

Introduction to CentaurPlus C21

Overview of the Horstmann C21 two-channel programmer and its primary features.

CentaurPlus C21 Programmer Overview

Control Panel Diagram and Components

Detailed labeling and description of the programmer's buttons, indicators, and display elements.

Manual Overrides and Functions

Boost Function for Hot Water

Instructions for temporarily boosting hot water for one hour.

Advance Function for Central Heating

Instructions for advancing the central heating to the next ON or OFF operation.

Programme Override Facilities

Understanding Override Modes

Explanation of permanent override modes: AUTO, ALL DAY, 24hrs, and OFF.

Setting and Programming

Setting the Time of Day

Step-by-step guide to correctly set the current time on the programmer.

Setting On and Off Times

Procedure for programming the heating and hot water ON/OFF periods.

General Information and Maintenance

Resetting the Programmer

How to reset the programmer to factory default settings.

Battery and Service Information

Details on battery backup, life, and user serviceability guidelines.

Understanding Programmers

Programmer Functionality Explained

Basic explanation of how central heating and hot water programmers operate.