Airconditioner noise normal ?

No, not normal sounds at all, you should hear only fan noise & maybe a "hum", not any sort of mechanical noise at all. Mine used to emit at times a pinging sound which was found to be the fan hitting the evaporator....

a good aircon is not noisey

however to answer your question.....you have vibration transmission from the refrigeration cycle...bit hard to determin where or why its eminating (cos i am not there) but if installed corectly it should not be happening...

it could be one or more of following:
compresser hold down bolts are to tight.
loose piping or other components.
timber is a good amplifier of noise and hence vibrations)...meaning that refrigerant piping is in contact with timber frame (I assume your caravan is timber framed) and is amplifying the refrigerant gas pulsations from the compressor.
suction (regfrigerant liquid/vapour) gurgling in the evaporator...this would be hard to rectify.
lots of other things too

if new take it back and get it looked at...no point havng a noisey aircon where you cant sleep

If it is an air command split then yes, they are noisy, particularly the compressor section. We have one in our van. You get used to it.

Some roof A/C's are also noisy though the latest versions are fairly good.

Hi Russellb,

My a/c was located in the cupboard but newer models have since been relocated under the seat. Anyway, the point being that while there was fan noise, there was virtually no vibration. Sounds like something touching somewhere that shouldn't be (member #1 seems to have the complete list).

Cheers

Captain

yes this unit is the small Climaster box unit under the seat with 3 air hoses leading to vents in the van.

It's brand new and the noise has settled slightly but still a very definate pulsing deep hum when the compresor is running, very different to the constant loud air noise from the vents, that I could live with.

Definately sounds as though something else is going on might give the manufacturer a ring

I'm very sorry to say it, but all caravan airconditioners are noisy, inefficient, expensive and crude 1960's technology.
I know - I used to own one.
I looked into fitting a household split back in 2001- and have never looked back.
I have installed a number of these for friends and never seen a problem ( A good mate is a "fridgy" mechanic and does the final gas work- I do all the rest.)
The Household splits are superior in every respect and about half the cost.
I know it's too late for you, but something to consider next time.
My latest van has an Inverter split which happily runs on a ONE Kva Honda on ecothrottle!
Cheers and good luck.