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Honeywell ST9400C Programmer (88608)

Separate timing. 2-wire installation. Override facility. Holiday mode. Automatic BST/GMT time change. Boost function. Building Regulations compliant, WEEE, RoHS.

  • 7 Day Programmable
  • 1, 2, or 3 On/Off Periods per Day
  • Digital Display
  • Suitable for Gravity-Fed & Fully Pumped Systems
  • 3 Pre-Set Programmes
  • 2 Wire Installation
  • Backlit Display
  • Battery Back-Up
  • Automatic BST/GMT Time Change
  • 1 Year Guarantee

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£79.99INC VAT

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Honeywell ST9400C Programmer is rated 3.3 out of 5 by 46.
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Rated 1 out of 5 by from Unreliable controllers I've recently replaced my controller, it was a little over the 2 year warranty period so had to buy again (in order to maintain compatibility with rest of the system). It's not the sort of thing I would expect to go wrong on a heating system but if you google "ST9400C faults" you'll soon find people have also had problems - circuits not switching on and off as they should due to the surface mount relays breaking down - components that one would expect to have a long service life given their ubiquitous use in automotive electrical systems that undergo far more severe conditions. For reference my faulty unit is a late 2014 date code - newer than the claimed "faulty batch" date codes on the plumbers & electrician forums (mid 2010 - mid 2011).
Date published: 2017-04-18
Rated 5 out of 5 by from Just the job I purchased this programmer for a customer who had the previous ST6400C programmer as an integral part of their Stanley Cooker/boiler. It was a bit more expensive than going elsewhere but it's Christmas, Screwfix had it on the shelf at a branch, so I could get the job done before my customers visitors arrived. They were more than happy to pay the small premium. I have fitted these programmers before so can give it top marks for features, reliability etc.
Date published: 2016-12-31
Rated 5 out of 5 by from Replacement unit Had a problem with my old controller. Either provided hot water or central heating. My heating engineer came out and recommended this unit. Said it would be easy for me to fit. He was right. Two screws to loosen, replace unit onto original backing plate and re-tighten screws. Five minute job. Now have perfect system and increased programming options.
Date published: 2016-12-24
Rated 5 out of 5 by from Complicated but good This programmer is not for the customer who wants a simple on/off clock, it has all the features for a domestic household who need to program their heating daily. Easy to install, wiring easy.
Date published: 2016-12-19
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I have Honeywell smartfit T8677B1006 which has been damaged can i replace it with the ST94006 as smart fix no longer being mafe

Asked by: Ke55ie
Whilst it is not a direct replacement the Honeywell RF2 Pack 3 (Part reference Y9420S2005) provides a solution with minimal upheaval as the use of wireless thermostats eliminates the need for additional wiring. The zone valves will need to be replaced with either V4043H or V4073A dependant on whether the system is an 'S' or 'Y' Plan. The programmer will need to be located close to a power supply, most likely the airing cupboard. The Smartfit base unit can be replaced with a 10 way junction box and all components wired into there. The existing electrical supply to the boiler can be utilised thereby negating any major upheaval.
Answered by: Honeywell Tech Support
Date published: 2017-04-20

Will this product replace my existing ST6400C programmer without the need to change the wall plate?

Asked by: OldGasser
The ST6400 and the ST6450 programmers can be replaced with the ST9400C Programmer without the need to replace the backplate or wiring, however we always recommend installing a new backplate when installing a new programmer.
Answered by: Honeywell Tech Support
Date published: 2017-04-05

I have a a glow-worm mastermind time switch connected to a glow-worm Galaxie boiler.will the Honeywell ST9400C successfully replace my old timer?

Asked by: Henhouse
The ST9400C is a two channel programmer, designed fir use with modern fully pumped systems. There should be no issue replacing the existing programmer as long as the system is a fully pumped system. If in doubt it is best to consult a heating engineer.
Answered by: Honeywell Tech Support
Date published: 2017-04-03

I have this model with my existing central heating system and find it reliable. Can it be used to run a hotwater tank with two immersion heaters without being attached to a central heating system?

Asked by: Blockage1
Immersion heaters are generally operating at 13amp. The ST9400C is not suitable for switching loads greater than 3 amp.
Answered by: Honeywell Tech Support
Date published: 2017-03-31

hi, will this model bined {connect }with my current relay box bdr91 as i have a cm921 with a faulty display that i want to replace witout doing any wiring

Asked by: maghater
No, the ST9400C programmer is not a wireless device and nor is it a programmable thermostat, which the CM921 is. The CM921 module can be obtained and connected to the existing BDR91, CMS921B1042.
Answered by: Honeywell Tech Support
Date published: 2017-03-31
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Specification
Brand Honeywell
Central Heating Control Type Programmers
Compatible Boiler Type All Boilers
Display Type Digital Display
Installation Type 2-Wire Installation
Manufacturer Guarantee 1 Year Guarantee
Manufacturing Standards Building Regulations Compliant, CE, WEEE, RoHS
Model No ST9400C
Pack Size 1
Pieces in Pack/Case 1
Product Depth 35 mm
Product Height 99 mm
Product Type Programmer
Product Width 145 mm
Programme Facility 7 Day Programmable
Suitable System Suitable for Gravity-Fed & Pumped Systems
Switch Type SPDT
Zoning Level Up to Two

Switching/contact rating: SPDT 3(3)A. H x W x D: 99 x 145 x 35mm. Backplate fit: Industry Standard. Suitable for underfloor heating.

Downloads

Instruction Manual