Pre empting the wiring info. Dug through old bits of info and..... ( I haven't any 701 timers kicking around at present so cannot physically check)
These should be the steps needed:
To by-pass the 1 hour timer.
You have a RED wire TO the controller which is your live feed
Also a YELLOW which goes FROM timer to heater.
You will need a 2 way switch with 3 terminals on the rear.
On the terminals on the switch you will have 3 connectors
Connect into the Red wire and put this spur on pin 1
Disconnect the yellow connector before the heater and connect the one that goes to heater to the middle pin and the yellow to timer to pin 3.
When your switch is in one position it will connect the two yellows and the timer will operate. In the other position the heater will run all the time.
As the red wire is still connected you will still have control over temp on the controller.
Hope this helps
E D I T - the difference in the controllers is denoted by the colour of the Eberspächer logo on the front - blue logo is BT and white logo is standard. (I think that I have got it the correct way round

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