Mine doesn’t always stay on all night does anyone know the problem? Book says 120 minutes is default time but can be overridden for longer running but I can’t find where it says how. Heater is an Eberspacher.
Only me have an ERF then 
Possibly only you STILL have an ERF 
I know some night heaters only stay on for a set time unless you turn the ignnition key the opposite way (if that makes any sense) so that power is on to the windows etc but your actual ignition is not switched on. I’m pretty sure my old Merc Actros used to be like that. The DAF I had before that was a temperamental barsteward though, sometimes it’d stay on all night, other times it’d last 2 hours, other time 5 or 6 hours. I hate nothing more than waking up at silly o’clock freezing cold, having to prat about with the heater, trying to get it to come back on again.
The night heater in my Merc Actros is like that. 2 hours running, unless the ignition is on one click.
its a design for ERF
otherwise the plastic cab melts 
I seem to recall the nightheater on my old EC was just a thermostat dial above the passenger side door. A little green light would come on in the centre of the dial when it was on. But if the light started to flash, it meant there was a fault and it would switch itself off. I can’t remember it turning itself off after a set time. Once it was on, it stayed on until you switched it off or the batteries go flat. Can’t remember if the ECX nightheater had the same controls though.
Ahh, yes. I should mention that on the Actros, 2 hours is how long it’s supposed to run for. If the ignition is off when you fire up its ‘auxiliary heater’, a message comes up on the dashboard computer screen that says Auxiliary heater on, 2.00 hours running, or something like that. It then counts down from 2.00 hours until the screen switches off.
If you have the ignition on 1 click it says auxiliary heater on, continuous heating mode, or something similar. If you then switch your ignition off it goes to 2.00 hours running and starts to count down.
There is also a timer that you use to set your night heater to come on at a set time, in fact two timers. I often set mine to come on half an hour or so before my alarm goes off. That way I wake up to a nice warm cab 
Simon:
There is also a timer that you use to set your night heater to come on at a set time, in fact two timers. I often set mine to come on half an hour or so before my alarm goes off. That way I wake up to a nice warm cab
Also useful during winter so that when all the other drivers are pratting about first thing on a Monday morning trying to de-frost their wind screens, yours is nice and clear as you climb in to a warm cab.
Not tried the night heater or mine yet as the temp has been very mild for the time of the year.
Will boost it up next week to see what happens.