Honeywell 
Y-Plan and S-Plan

      

 

The following animations show each mode of operation by highlighting the path from the programmer to the boiler.
Y-Plan
Hot water only 
Central Heating only

Hot water and central heating
Both calling
HW satisfied, CH calling
HW calling, CH satisfied
Both satisfied  

S-Plan
Hot water calling
Central heating calling 

Flame Rectification
Basic AC and an explanation of flame rectification 
Earthing  (Word document)

The Honeywell web site has a vast amount of information and includes details of all the Sundial plans.
Have a look at http://www.honeywelluk.com/Default.aspx


Please note that all information on this web site is provided 'as is' . Whilst every effort has been made to ensure its accuracy, no responsibility can be accepted for any damage, loss or other misadventure as a result of its use.

Page created and maintained by John Turnbull