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Product at a glance

This product is discontinued

Electronic Programmer

Two channels with 7-day programming and independent timing of heating and hot water. Part of a range of electronic programmers that offer up to four independent channels and feature a large, easy to read display and simple menu-driven programming. Three and four-channel models are for multiple zone control, with single and two-channel models used with combi boiler systems and stored hot water systems.

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Model Replacement
ChannelPlus H27 The above units use the same backplate as H3747 and only require simple wiring changes * C1727 requires backplate change and rewiring (economical option) H3747 or C1727*


  • Time control of most domestic gas or oil-fired central heating systems
  • Combi boilers
  • Stored HW systems
  • Underfloor heating systems
  • Zone Control – time control of multiple heating zones


  • Flexible controls
  • No need to worry about resetting the clock for Summer/ Winter time changes


  • 2 channels
  • 7-day programming
  • Back-lit LCD display
  • Simplified menu-driven programming
  • Advance and boost on each channel
  • Preset clock
  • Automatic Winter/Summertime changes
  • 9-pin wall plate
  • 7 years no quibbles warrant


Contact rating 3 (1) Amps 230V AC
Contact type Micro-disconnection Voltage-free (not H37XL)
Supply 230V 50 Hz
Pollution degree Degree 2
Class a software Type 1 Control
Enclosure protections IP30
Double insulated Yes
Operating temperature range 0° C to +40 °c
Battery Lithium
Case material Thermoplastic flame retardant
Dimensions 101 x 163 x 37mm
Display Back-lit liquid crystal
Clock 24-hour or 12-hour am/pm
Displayed time adjustments 1-minute steps
Switched time adjustments 10-minute steps
Programme options On, Off, All Day, Auto & Holiday
Operating periods Per-day 3 for each channel
Override (each channel) 1 or 2 hour boost, 1 or 2 hour extension to On period, instant advance
Mounting 9-pin wall fixing plate