replaced ST6400 with ST9420C and DT92E - optimum settings?

12 Jun 2011
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United Kingdom

Have just replaced a problematic Honeywell ST6400 with a sundial RF Pack 2 (ST9420C and DT92E)

Other than obviously setting my chosen times is there any other settings I should be changing, or are all the defaults okay? such as cycle rate, min off/on time, optimum start, stop, dealyed start etc etc

Thanks in advance
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someone had mentioned to me that the default settings are for a gas boiler and I have oil - they said perhaps the following settings should be used

min on/off time = 4
Boiler cycle rate = 3

The defaults are:-

minimum on/off time = can be 1, 2, 3, 4 or 5 minutes - default is 1
Boiler cycle rate = can be 3, 6, 9 or 12 per hour - default is 6
proportional band width = 1.5 - 3.0 degrees - default is 1.5

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would having it set to the wrong settings have caused any damage to anything? just that I had asked my boiler man to check the settings and he obviously hadn't done so - and I have had several issues with boiler cutting out, overheating and the amber light coming on and having to be pushed to get boiler to fire up - could any or all of these have been caused by the min on/off time and boiler cycle rate being set incorrectly?

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