Ultitube Pressure Equalisation Membrane - Does it stop you pressure testing?

[Mike_J_Smith]

I posted this in the Aquacomputers English forum, but noticed the last few posts hadnt got any responses so thought I'd ask here too as I know others have these.

I'm finally getting round to building a loop that I started 2 years ago! I bought a "ULTITUBE D5 150 PRO reservoir with D5 NEXT pump" and have been playing around with some potential loop design.

As it's my first time doing this, I thought I'd stop and check the first line I put in, which goes from a radiator to the inlet on the Ultitube.

So I put a plug into the outlet of the ultitube and attached a pressure testing pump to the radiator and it failed completely. All I got was a weird hissing / puffing noise.

I started testing sections of the loop and eventually tried just the Ultitube by iteslf and found the same hissing / puffing noise. Then I remembered the pressure equalisation membrance in the lid of the reservior and now I'm wondering if that is the problem?

Will it stop me pressure testnig the loop? Is there a way around it?

 

[Mike_J_Smith]

I found my answer usng the search tool on the aquacomputer forum! From another post there:

Thank you for contacting us! If your Ultitube came with a pre-installed D5 NEXT pump,
it must be the "PRO" version of the Ultitube. All PRO version
Ultitubes come with a pressure equalization membrane installed in the top lid
of the reservoir, so will not hold pressure by design.

If you want to pressure check your loop including the reservoir, you can try to
put some plastic foil between glass tube and lid of the reservoir or use this
lid without membrane: https://shop.aquacomputer.de/product_inf…roducts_id=3865

 

[Mysterae_]

This is good to know as I'll be building a loop with a Utilitube soon and would probably have had the same question when the time came!

 

[Mike_J_Smith]

This is good to know as I'll be building a loop with a Utilitube soon and would probably have had the same question when the time came!

It’s actually a proper pain in the arse I think. I tried with some cling film but unsurprisingly that didn’t work.

You can buy a lid without it, which I might do just to get the reassurance. £10 plus postage though; they should really have been included it or at least a cheap plastic lid for testing.

 

[Mike_J_Smith]

I've ended up ordering the lid without the membrane, I don't think I'm going to be happy doing this build without beng able to pressure test and this is the easiest way to do it

 

[Bubo]

This membrane sounds like a pure snake oil gimmick to me anyway. Not sure if the pressure fluctuations this thing is supposed to solve are that much of a problem in the first place for a cooling loop. No other benefit from having what is effectively a breather in a water cooling setup that I can see. They claim it won't let coolant out in their blurb, but if you can hear air coming out then that will be a path for evaporation to get out as well.

 

[Mike_J_Smith]

Well, I got the lid without the membrane and it works as expected. However, I kept on getting tubes popping out of the connectors, which is when I read again what bar you’re meant to pressure test at! I’d been using 1 bar, because that’s what the pressure gauge seemed to imply, but actually more like .3-.6 is good for systems.

So now my tubes aren’t popping out and I’m thinking maybe I just over pressurised the system and the membrane would have been ok otherwise? Nevermind, I don’t think I’ll put the lid with the membrane back on anyway.