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halfaguy80
24-08-2013, 07:27 AM
Hi everyone,
First time posting here so sorry if it's a little bit mixed.
I have a GAH fridge unit mounted on my van but I want to remove it and
connect up to my trailer, installation is not a problem however I am struggling to think of a way to power the compressor, I was thinking about keeping the vehicle mount kit and using a 240v electric motor to replace the engine power source. Does anyone see any issues with this or is there a better way to power the compressor. thanks :)

halfaguy80
24-08-2013, 07:29 AM
PS, I need to keep the 240v supply so I can power from mains at the yard to generator on the road
ta

Rob White
24-08-2013, 08:46 AM
.

There is no reason at all why you can't do it
with an electric motor. Just choose one that is
large enough and make sure the belts and
mounts are all inline and tensioned correctly.

Mobile fridges are powered from electric motors
and engines combined on the same chassis, so
as long as the correct motor is chosen I see no
issues at all.

regards

Rob

.

chemi-cool
24-08-2013, 09:57 AM
Is the condenser in your van as well?

In any case, hermetic unit will be a better idea as you will not loose any refrigerant, smaller unit without belts.

install monkey
24-08-2013, 10:00 AM
https://www.google.co.uk/search?q=2000w+inverter&oq=2000w+&aqs=chrome.1.69i57j0l3.5136j0&sourceid=chrome&ie=UTF-8#fp=ab709e5c718a588b&q=3000w+inverter&tbm=shop
just get some extra batteries

halfaguy80
24-08-2013, 08:25 PM
Thanks Rob
this is what I thought but wasn't sure, the next problem I have is finding a motor big enough what rpm does the compressor need to turn at.

halfaguy80
24-08-2013, 08:34 PM
Hi chemi-cool
I had planned to put the condenser on the roof of the trailer, forgive me for being ignorant but
what is a hermetic unit

halfaguy80
24-08-2013, 08:42 PM
I spoke to an auto electrician about extra batteries he said i would need loads and it wasn't a great move, thanks for your thoughts though

Rob White
25-08-2013, 01:00 AM
Thanks Rob
this is what I thought but wasn't sure, the next problem I have is finding a motor big enough what rpm does the compressor need to turn at.


Your motor will be 1450 ish rpm but the comp might
rotate slower. Remember the comp was fed from the van
engine and that varied its speed as it revved through the
gears and it's idle speed would be about 1500 rpm.

Use the same size pulleys as already fitted to the engine
and compressor and you will be fine.

Rob

.

halfaguy80
25-08-2013, 10:08 AM
[QUOTE=Rob White;284386]Your motor will be 1450 ish rpm but the comp might
rotate slower. Remember the comp was fed from the van
engine and that varied its speed as it revved through the
gears and it's idle speed would be about 1500 rpm.

Use the same size pulleys as already fitted to the engine
and compressor and you will be fine.

Rob

thanks again rob, I had assumed that the compressor had some sort of limiter so that it did not over speed but as I plan to connect it to a constant speed I can now look for a motor that turn around that rpm.
Looking more confident to my wee project now.
Many thanks
Gordon

chemi-cool
25-08-2013, 02:25 PM
Hermetic unit is based on hermetic compressor, no belts, no leaking shaft seal.

Less currant consumption, safety.

I would suggest you give it a thought.

adding to Rob's post, there are 1000rpm motors on the market but 1450 rpm is ok, you just need to get a belt puly the same diameter as on the comressor.

halfaguy80
25-08-2013, 09:01 PM
Hermetic unit is based on hermetic compressor, no belts, no leaking shaft seal.

Less currant consumption, safety.

I would suggest you give it a thought.

adding to Rob's post, there are 1000rpm motors on the market but 1450 rpm is ok, you just need to get a belt puly the same diameter as on the comressor.

Thanks for that chem-cool I will look into that idea too I have the old mounted compressor that is complete with the wiring to the control box so may possibly stick with the pulley system, simple stupid if you know what I mean ha ha
Cheers :D

flyinkiwi
25-08-2013, 09:42 PM
I would strongly recommend you not use a hermetic compressor in a road application, as the bouncing on the road can result in internal damage to the compressor.

If you still wish to use something other than an open drive, I would suggest you use a semi-hermetic compressor, as they do not have any internal mounting springs to come adrift from.

Unless of course you have perfect roads where you come from...

halfaguy80
26-08-2013, 07:34 AM
I would strongly recommend you not use a hermetic compressor in a road application, as the bouncing on the road can result in internal damage to the compressor.

If you still wish to use something other than an open drive, I would suggest you use a semi-hermetic compressor, as they do not have any internal mounting springs to come adrift from.

Unless of course you have perfect roads where you come from...

Ha Ha I drive around Argyll the worst roads in the flippin UK, Thank you very much for your advice I was looking at the hermatic compressor so much so that I have emailed GAH to ask what size they would recommend will just send another one asking about a semi-hermetic one instead.
Cheers:)

chemi-cool
26-08-2013, 03:00 PM
Semihermetic is very heavy [around 100kg].
Hermetic compressors are widely used in food vans, motor homes, boats, etc.
A bump that will damage your compressor, will destroy your van.