Drayton thermostat

[oodatdeer]

Bought replacement Drayton RTS1 and discovered to my surprise that the original was RTS4??? These are for COMBI boilers aren't they?
My boiler is Baxi Solo3.
Could it be that the RTS4 was wired to act as RTS1 because it looks as if an extra wire loop has been inserted.
Daren't plug new thermostat body on till I'm sure it wont damage anything ... or ... should I replace with RTS4 and accept wiring configuration?
Thanks for any replies.

 

[giblets]

What were your reasons for changing the stat in the first place?

 

[oodatdeer]

giblet ....(thanks for reply). I replaced motorised valve and set it for refilling.
When the valve is powered it is supposed to click into normal operation automatically ... it didn't ... I then noticed the thermostat did not make faint click when temperature knob was turned to both extremes and assumed a fault. I have been informed that the thermostat is part of energising the motorised valve to work correctly.
Must add ... I'm fairly sure the m/v is wired ok because I removed and replaced wires one at a time.