What an interesting device. Good find.

I googled the membrane looking for a replacement period
and found it works virtually for ever
http://www.coltrisub-asiapacific.com/nitrox_ms/

I'm a bit perplexed how the two stage system is implemented
in that unit as it is the input pressure to the membrane that
controls the %age output of the mix. (100psi->40%)

Have you got a price? How much extra is the membrane over
the standard 'simple' compressor?

nigelH

I know a couple of dive shops and liveaboards that use membrane system
compressors to produce nitrox.  You have to monitor them to ensure you're
getting the blend you want, but they all seem to work well.  The thing to
research before you buy is the life cycle of the membrane and the cost of
replacement.  If it still makes sense, go for it.

Lee

Depot is only 7 miles from me.  I know a few people who have Coltri
stuff, not membrane though.  " minor niggles "
1) I have had to replace the stop / start switch on 3 of them as they
have burnt out.
2) The capacitor in the start-box has split its casng on 2 of the units.
Neither are major probs, especially when they are only 20 mins away,
just something to be aware of as I am sure they are common parts across
the range. How much is the unit?

Having said that, it is fairly solid kit!

How much is it?

Keith

Dear all,

Thanks for your comments.  I'm still awaiting a price from SMP so will keep
you posted.

Andy

I finally had a price back: £5500 plus VAT.

Still tempted though...

Andy