Honeywell ST9400C Programmer Product Code: 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


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.
Additional Information
Technical Specification
  • Brand : Honeywell
  • Manufacturing Standards : Building Regulations Compliant, CE, WEEE, RoHS
  • Product Height : 99 mm
  • Display Type : Digital Display
  • Product Type : Programmer
  • Programme Facility : 7 Day Programmable
  • Zoning Level : Up to Two
  • Central Heating Control Type : Programmers
  • Model No : ST9400C
  • Product Width : 145 mm
  • Product Depth : 35 mm
  • Pack Size : 1
  • Switch Type : SPDT
  • Suitable System : Suitable for Gravity-Fed & Pumped Systems
  • Installation Type : 2-Wire Installation
  • Compatible Boiler Type : All Boilers
  • Manufacturer Guarantee : 1 Year Guarantee
  • Pieces in Pack/Case : 1
Product Contents
1 off ST9400C 2 channel heating programmer
Delivery & Returns


Standard delivery: €15

Free delivery on all orders over €70.00

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Hopefully you won't need to return an item, however, if you do, it is our aim to make this as simple as possible. By following the guidance below you can help us to help you when a product is not what you expected, or is faulty. Your statutory rights are not affected by this guidance.


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€81.95 Incl. 20% VAT

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Honeywell ST9400C Programmer is rated 3.4 out of 5 by 70.
Rated 5 out of 5 by from Replacing previous programmer This replaced my previous programmer whose backup battery had failed. It went straight onto the existing backplate and was much easier to setup. Auto changes BST/GMT.
Date published: 2017-10-18
Rated 5 out of 5 by from Direct replacement Easy to install and reliable. This was a direct replacement for faulty unit which was over 10 years old. It was also £6 cheaper than original.
Date published: 2017-10-11
Rated 5 out of 5 by from Good replacement The out going model kept resetting itself. This was a direct replacement using same back plate needing no rewiring. It simply clicks in place and up and running in 20 mins. Simple!! Clearer display than older model and handy holiday function. Possibly cheaper online but with screwfix click and collect I had it the same day and knew it was in stock before collecting.
Date published: 2017-10-02
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
Rated 5 out of 5 by from All good Firstly I've only had this item a couple of days so the reliability score is, ironically, not that reliable but hopefully it will be accurate. It was purchased to replace a second Drayton LP722 programmer which failed within 6 months, the previous one only lasting 2 years. Hopefully this one will have a longer lifespan. Mounting plate compatible with the Drayton so it was an easy remove and replace, no wiring to be done. Honeywell provide a compatability chart on their website too so you can check. The programmer has plenty of functions and features like boost times and holiday modes and it was a doddle to set up. It seems well built and worked straight out of the box.
Date published: 2016-11-01
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