User Manual homexpert by Honeywell THR842DUK Wireless Digital Thermostat What is a room thermostat? ...an explanation for householders If your heating system is a boiler with radiators, there will usually be only one room thermostat to control the whole house. But you can have different temperatures in individual rooms by installing thermostatic radiator A room thermostat simply switches the heating system on and off as necessary.
Honeywell THR842DUK Wireless Digital Thermostat About your new wireless thermostat Quick reference The THR842DUK is an easy-to-use thermostat designed to maintain a comfortable environment when you Cooling system is ECO mode countdown Heating system is Press to change...
Operation homexpert by Honeywell THR842DUK Wireless Digital Thermostat On/off switch and frost protection Heating or cooling control Press and hold the ON/OFF button as shown at left to turn the The thermostat is pre-set to control only your heating system. If Press and hold both buttons for 5 seconds thermostat on or off.
Operation homexpert by Honeywell THR842DUK Wireless Digital Thermostat Temperature control Energy-saving ECO mode When idle, the thermostat displays the current room temperature. The ECO mode overrides thermostat settings to maintain a different Current room temperature Press to enter ECO mode You can press the p or q buttons at any time to see the “target”...
Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat System installation Install relay box Installation procedure The relay box is wired directly to your heating or cooling equipment. The thermostat 1 Install relay box communicates with the relay box using a wireless RF signal to control the system.
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Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat Connect system wiring Wiring diagrams Connect wiring from your heating or cooling Burner (direct control) Combi boiler equipment to the relay box as shown at left. See wiring diagrams on page 15 for details.
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Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat Activate batteries and test thermostat Test thermostat (continued from page 16) Grasp and pull to remove the thermostat cover. Discard the plastic 5 Press the q button once. tab inside to activate the batteries, then test as shown below.
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Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat Test thermostat location Install thermostat (continued from page 17) Test signal strength to find a suitable location for the thermostat The wireless thermostat can be mounted in the table stand, before installation.
Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat System test Installer setup After installation, you should check to make sure the system is Installer settings allow you to customise how your system Set temperature to maximum working properly.
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Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat Installer setup functions Installer setup functions ** Factory default setting Enter Installer Setup (see page 19), then press for access to system settings Function Description Setting Options Function Description Setting Options...
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Installation and Setup homexpert by Honeywell THR842DUK Wireless Digital Thermostat Customised settings for your system Description of functions Ot Minimum boiler off time: Check proper setting LL Minimum temperature: When the q button is Your heating system Changes required Setting Options for your system (see page 24).
Try the test procedures described on pages 16-20. • If the problem cannot be corrected, contact Honeywell Customer Care for assistance (see back cover for contact information). • If above remedies cannot resolve the problem, the thermostat may have to be moved.
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Appendix homexpert by Honeywell THR842DUK Wireless Digital Thermostat Re-binding procedure Re-binding procedure (continued from page 28) If you must replace a wireless thermostat or relay box, the system 5 Press the p button repeatedly until the display shows “CLr.” will not work until both devices can communicate with each other.
Honeywell THR842DUK Wireless Digital Thermostat Limited Warranty Declarations, disposal and recycling Honeywell warrants this product for 1 year from date of purchase. We undertake to replace or Declaration repair at our discretion, products should they become defective within 1 year solely as a result Honeywell hereby declares that this wireless product is in compliance with the essential of faulty materials and or workmanship.