air conditioning duct query

I have had an air condionig guy install a split air conditioner, he has fitted a 100 x 75 standard size cable duct (colourbond) down the wall and it sits proud, enough to stop a window openig

Does anyone know if smaller duct is sold anywhere, he says all the same size so cant change it
I only need it about 50 x 50 to fit his pipes but looks suggest it should be colourbond

thanks

Doug

Just go to a sheetmetal shop or to Lysaghts in Greenacre and get one folded up to the required size.

An option to what Barry has said. I'm having some units installed shortly, the Installer uses PVC ducting with clip-on tops for future access. The size is around what you have said, but I assume other sizes are avaliable.

Alternatively relocate the duct.

PVC duct in that size can be purchased from Electrical Wholesalers.
You have a choice of grey or grey but you can paint it easily enough.

I went to Stratco & chose what color colorbond, and also the size I wanted, and they formed it for me (about 1 week lead time).

I made it from 2 U shaped sections - the base around 50mm high by 80mm wide, and the cap is 80mm wide by 10mm high, and held on with half a dozen pop rivets up each side.

The all up cost for both bits, running 2400mm, was $36.

Thanks all

Doug