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Honeywell Sundial RF2 Pack 2 Y9420H1008

Honeywell Sundial RF2 Pack 2 Y9420H1008

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Item Code: 312093
Expected Delivery:  5 - 10 working days
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Need Help?  0800 181 4488
Ex. VAT £185.92 Inc VAT

Additional Information

Brand Honeywell
Lead Time 5 - 10 working days
Channels 2
Interface Digital
Program Options 7 Day
Type Programmable Thermostat
Wireless Yes
Manufacturer Part No: Y9420H1008


Honeywell Sundial RF2 Pack 2 Y9420H1008

This pack contains:

  • Wireless enabled programmer (ST9420C)
  • Wireless room thermostat (DT92E)

This pack is Ideal for adding a room thermostat to a traditional system.

In a stored hot water heating system which has no room thermostat, the existing wiring can be used to provide Boiler Interlock by fitting Sundial RF2 Pack 2.
This has a full programmer, with independent heating and hot water and a built in wireless transceiver to enable a wireless room thermostat, maintaining the traditional layout of separate time control and room thermostat. It can also be used on new systems. Because the room thermostat and the programmer communicate, energy saving and operating benefits are also enabled:

Programmer override from the thermostat.

†TPI control: Time Proportional and Integral (TPI) control is a method of calculating the demand from a room thermostat, controlling the boiler so that it fires for shorter periods as the temperature approaches the set point. This can offer savings of up to 10% of energy consumption (in a single cycle steady state test).

*Optimum Start: To save energy, let the controls work out when to come on to suit when you want to be warm. Every day the boiler will start at the latest possible moment depending on the weather.

**Delayed Start: Once you have programmed your earliest start time, the controls will delay the boiler firing time on warmer days, when it is possible to save energy.

***Optimum Stop: Saves energy and money by switching off before the normal programme time whenever possible.

This RF2 Pack 2 Features:

  • Energy saving TPI control (see FAQ TPI Control)
  • Wireless enabled upgrade
  • Two way wireless communication
  • Wireless signal strength indicator
  • Built in Ecomomy or Comfort programmes on ST9420C
  • LoT display for easy programming on ST9420C
  • ST9420C fits on industry standard backplate
  • ST9420C is a direct replacement for ST9400 and ST6400 models
  • ECO setback function on DT92E
  • Frost protection on DT92E
  • Tabletop stand supplied for DT92E
  • Battery powered - no wiring for DT92E