Don't Use Aquarium Pumps To Pump Cold Air

[Tyred]

From everything posted it would appear the the problem is the air being heated when compressed and a solution is to try an cool it. For cooling (if the pump is in a fridge) a solution could be to cool the pipe though ice (greater surface area leading to greater cooling). Either that or pump the air into a rigid container full of sterile liquid at the base and having another pipe at the top to pass the compressed air on.

Of course, these are dodgy solutions but they would work. I used the ice solution when my fish tanks (a long long time ago) were getting too hot and putting cool air into them seemed to be the easiest solution.

 

[barfridge]

ok, if you want to make do with only one hole, run 2 lots of ducting through it and use 12 volt fans to push air around. With chilled air I'd have the inlet into the esky at the top, and be sucking the exhaust air from the bottom.

Or perhaps it would be better the other way around, it's worth experimenting with.

As for flow, you can get lower noise 12v 120mm fans that will push 100cfm (into zero load), which is 2.83 cubic metres/min or 2830 litres/minute. Of course in a push-pull configuration you will get much less than this, but still more than sufficient for your needs.

 

[Nui]

FOR SALE: 60lt/Min Aquarium Air Pump. Runs 8 tanks. Heavy duty. Hardly used. Reluctant Sale - Going Overseas to a tropical climate!

[post="124186"][/post]​

:lol:

 

[PistolPatch]

Sorry, lost track of this thread. It turns out that my esky is maintaining temps witha bare amount of effort. 1 600ml freezer block changed twice daily maintains the brew at ale ferment temps.

Thanks BF. I didn't realise that you could get computer fans so small but it looks as though you'd still need a pretty big hole to run your ducting through (like about 20cm) so this won't work for me as I need the esky as a mash tun as well. Really want to keep the one hole at 25mm.

Managed to try some dodgy stuff the other day Tyred, just out of interest. I ran the pump through my immersion chiller which I sat in the fridge. This pumped air at a constant 6 degrees which was interesting but of course chews up some fridge space.

The pump has a plastic manifold that feeds 8 aquarium hoses. If I manage to find some thin copper tubing, I might make 8 lots of straight tubing and run them up the back of the fridge to avoid wasting space and then re-attach them to a second manifold at the top resulting in one large outlet. I'd imagine that this would do better than 6 degrees.

Unitl then I'll use the damn thing to dry syphon hoses unless Nui wants to buy it!

Thanks again,
PP