Good question I would be interested to know that as well

I don't believe pressure testing is something necessary. These systems aren't under high pressure in by any means. Your requirements should be listed with the pump you're utilizing. Um, something like the pump being able to lift three metres. Testing normally is comprised of filling the loop and then checking for leakage. That testing can be done outside of your final installation and would be far more indicative of whether a fault would present itself, no?

I mean, if the loop is sealed and you add pressure, you're basically testing variation in ambient temperature and how that effects the captured volume. Which may explain the pressure drop you see.

Also consider:
I think very small particles in the water will seal any microleaks.
I once experienced this with a pump adaptor sealed with teflon tape. It leaked a few drops but that stopped after 1-2 days and it's dry since then.

This is only my opinion and how I see Dr.Drop fitting into this testings and any testing you conducting.

My loop is big and quite complicated consists of 3x GPUs, CPU, 4x D5 Pumps, 2x High flow USB meters, 8x 12TB WD Enterprise drives in which 2 of them are watercooled, they are at the back where no air is possible + 4x 480 Nemesis Radiators and ton of hard tubing.

Why I mention all this, because for me to take any of that apart for any reason is whole day of work and this system to be fully bleed it takes a month, even 2 in order to be as silent and to perform at its peek .

About 5 months ago I took 1 of the GPU blocks apart to see how well the Biocide works with Distilled water and weather I want to continue on using it, its been 2.5 years of constant use. I didn't wan to put the same block back on because I have 3 spare blocks, I always have extra parts in case i needed.

So I put that block on and assembled the loop, filled with water and as always, while filling with water I use external PSU so my system has no power, and what do you know! while the water was going through the system I had very small leak and the water was running at the back along the M/B.
Dr.Drop lets you test your blocks or your whole system prior to assembly or filling with water and I think that might be the main reason for that tool, there should be some allowable pressure drop tolerance so you not wondering if other factors casing the pressure drop but then again, the size and complexity of the loop will play role in readings as well.

That's what I was referring in my first response, if you run the same test with the same staring pressure to see if the pressure drop to the same reading

Citation de "aquacc32"

Also consider:
I think very small particles in the water will seal any microleaks.
I once experienced this with a pump adaptor sealed with teflon tape. It leaked a few drops but that stopped after 1-2 days and it's dry since then.

Hm..with water I honestly think is not as you imagine, once water will find even micro opening, it goes for it and gets worse and if you counting on any particles that might be in your loop to clogged the suppose micro leak/ potential leak, you should check your loop, you shouldn't have any dirt in there.

I won't quote your post with your explanation, Dundys; interesting and appreciated. It makes sense. That's some system.