Could somebody give me a rough figure for how much diesel a 13.6 metre fridge trailer would use in 24 hours, running at -25 degrees on a hot day? Ta!
Good question, would be better to have on continous mode in those conditions so a wild guess would be 1 - 2 litres an hour but that is a wild guess. 
It would depend on the condition of the trl and how good it can hold it’s temperature,an old boy once told me it usually is about 0.5lts an hour once it has got the temperature down to -25.
Didnt someone leave their night heater on after leaving the truck on a weekend off,he asked how much the heater used,which was a small amount per hour.
Well. a normal tank is about 200 litres. A good trailer, something like a Cherau would probably be on about 50% of the time on auto on a hot day. More during the day less at night. Usual thing is to set it for about minus 18 and turn it down a couple of hours before delivery, there are very few things that make any difference between minus 18 and 25. Just think of taking a lump of meat out of the deep freeze and how long it takes to defrost. So back to your question, a good Cherau will use a tank, bearing in mind the above about every 5 or 6 days. You get something like an old waterlogged G&A and it will get through a tank every 2 days. A modern fridge will probably have a range of settings, what they call “smart reefer”. If you learn how to use it properly you can cut the fuel usage dramatically. All the above obviously depends on how often you have the doors open of course. Most fuel is used getting it initially down to temperature rather than maintaining it.
When I do a 400 mile round trip (in a rigid) and run the freezer for 200 miles it costs me about £20 less than if I run the freezer for 400 miles. Doesn’t factor in any harsh acceleration or traffic jams though so only a rough guess.
toby1234abc:
Didnt someone leave their night heater on after leaving the truck on a weekend off,he asked how much the heater used,which was a small amount per hour.
I think a fridge motor will use a fair bit more fuel per hour than a night heater. 
A lot also depends on how cold the load is before its put into the trailer.
The chillers are not really designed to to reduce the temperature of the load they are designed to maintain the temperature of the load.
What I mean is if you put a -12 load into a trailer and put the chiller on -25 it will be flat out trying to bring the temperature down.
Its best to make sure the load is a cold as possible before loading it and that will save a lot of diesel being wasted.
So what are we saying a day then ? Roughly 25 litres a day or more/ less ?
Another question.
When would you use stop/start, and when would you use continuous, and why?
Harry Monk:
Another question.When would you use stop/start, and when would you use continuous, and why?
I always use continuous as although the chiller is always running its not actually doing that much. Its also better for the load as the temperature remains constant in the reefer.
I only use stop start when I’m in an area such as a housing estate (yes there are drops where this happens) or MSA with drivers trying to sleep where leaving it on constant would cause a disturbance
dieseldave:
toby1234abc:
Didnt someone leave their night heater on after leaving the truck on a weekend off,he asked how much the heater used,which was a small amount per hour.I think a fridge motor will use a fair bit more fuel per hour than a night heater.
Yeah that’s just what I thought 
Squiddy:
When I do a 400 mile round trip (in a rigid) and run the freezer for 200 miles it costs me about £20 less than if I run the freezer for 400 miles. Doesn’t factor in any harsh acceleration or traffic jams though so only a rough guess.
Deep frozen is usually fine on auto start. The only time they usually tell you to keep it on constant are delicate things like strawberries or cream cakes where you need to keep a very steady temperature. Ice cream is the only deep frozen thing i would keep it on constantly.
Harry Monk:
Another question.When would you use stop/start, and when would you use continuous, and why?
I would use continuous if nighting out in the summer as a steady drone all night is easier to sleep to and also on hot days maybe because it keeps temp more constant. Start stop when cold as fridge might not actually run much if its cold outside ( I’m talking chilled here )
If it’s really cold outside and you have chilled on (+2 to +4) the fridge will heat to maintain the temperature. I would still have it on auto unless it was really delicate.
Some of the US internet cost tables I was reading suggest a gallon per hour, although that looks like a US Gallon, it seems rather excessive, other forums are suggesting .75 to 1 gallon per hour running continuously at -10
Our own multinational hauliers suggest between 1 & 4 litres per hour.
freightbestpractice.org.uk/d … ction=save
Opens in PDF after download
Back in the 80s my fridge used nearly as much as the Truck…
i used to carry yeast and the they where locked onto constant, i was told they had to be as yeast naturally heats its self up.
my guess would be 20 / 25 litres per day. but it’s only a guess as it has been a while since i’ve done fridges
stevie
Harry Monk:
Another question.When would you use stop/start, and when would you use continuous, and why?
HM av pmd ye
ye runnin an old fridge there if ye doin that… should be intermittent, the Fridge ye have there is old by the sounds of it
what is it ye runnin ?
Keep it runnin if no intermittent…and it must be consistent… , ye can switch off but ye need to restart once the temp starts to drop… all changed now