Silly question but im doing my first night out soon during winter. Can you run a night heater all night long without flattening the batteries. Sorry if this has already been posted but couldnt find a similar thread.
Sure! Even if batteries are quite old they should easily last a night. With new batteries heating can be consantly on for 48 or more hours, and you will still start your engine.
Ahh great just had new batteries last week. Thanks for the advice.
Just don’t have it on full pelt. You’ll end up overheating yourself. Get it comfy then turn it down just a slightly. Oh I also find having a dash vent opens allows a bit of cool air for circulation
Cheers for the help
I run mine all year to keep the moving parts working so it works when Winter comes.
Run the air conditioning as well for the same reason.
Usualy find that a night heater will cut out before it flattens the batteries, it takes a certain voltage to fire the glow plug up, once its running it runs off the heat in the combustion chamber the voltage it uses is to drive the fan. If you have a dodgey battery the heater wont fire up any way, I,ve had it were the waggon starts ok but the nightheater won,t work and when checked out it has been a bad cell in one of the batteries.
A few of our lads have had flat batteries after running night heaters all night in new shape fh’s
rick parfitt:
A few of our lads have had flat batteries after running night heaters all night in new shape fh’s
FH’s can’t cope with a long weekend parked up in the height of summer without a good possibility of needing a jump start… 
…unless you turn 'em off at the mains.
Its the same for the fridge and freezer in our FH’s, once the battery gets to something like 21 volts they start to shut down. Careful that you never turn off the battery until the cab heater has run down to cool itself, if you cut the power when hot it melts the plastic parts inside!
Inside of my sleeper box when I was doing some agency work. Now I think I know why the night heater didn’t work…
Well cheers for all the help. I spent a night out in Scotland the other week and it was getting on for -7 degrees. Ran the night heater all night and the truck started no probs. In the morning.
Minus 9 last night. No night heater. Didn’t notice it was cold until I went to get up. Heater on and another 15 mins in bed.
happysack:
Minus 9 last night. No night heater. Didn’t notice it was cold until I went to get up. Heater on and another 15 mins in bed.
+1 best way…set the alarm,leap into action,ding the heater,then collapse back under the cover again for a while till the chills off…although,according to some,you cant be gassed with the night heater running even on cold…or would that open up another debate>> 