Hello, I recently purchased an Ultitube with D5 Next reservoir/pump combo (part 31400) (no leakshield, just the basic unit). I have been trying to leak test with a pressure tester before installing it in my loop but I find that it loses pressure quite quickly. It generally takes about 10 minutes to lose pressure entirely so it is not instant but definitely not considered air-tight.

I have purchased a separate lid without the pressure equalisation membrane and am testing with that. I have verified that the top has the rubber gasket installed, and have verified the rubber seal where the pump attached into the pump top is there as well. There does not seem to be any rubber seal between the pump top and bottom of the cylinder though. I have uploaded some photos of the unit here: #mce_temp_url#

I am just wondering if there is anything obvious I've missed or if there is something else I need to consider. There doesn't seem to be any obvious damage anywhere and everything looks fine cosmetically.

I have, of course, tested the leak tester with another component and all is fine there!

Many thanks