Capilary tubes- new to me?

[Sir Patrick]

What are these, how do they work and what makes them adjustable to your needs?

I was recently told they should be put in place of flow restrictors and are more adjustable to your exact needsand efficiant? Looking for more info.

Never heard of these before.

[Preuss Pets]

Spectrapure units have come with these standard for some time now. They are adjustable in that you can shorten the length to dial in the right ratio. Other than the adjusting mentioned above, I'm unfamiliar however with other features that would set them apart from the push in type flow restrictors.

Steve

[Sir Patrick]

Thanks Steve-

Your information is, as always, invaluable. Much appreciated.

[AZDesertRat]

Capillary tube flow restrictors look like a piece of spaghetti with a small flange on one end. You insert it inside the waset line on your RO or RO/DI system and it causes the backpressure required to force water through the RO membrane.
They differ from a fixed restrictor in that you use a razor blade to trim the length of the capillary tube to create more or less back pressure to change the amount of waste versus treated flow. Most vendors think we are dummies and know nothing about fine tuning a piece of equipment so include fixed ofrice type restrictors on their systems and unfortunately theye are rarely correct for the application. Since all of us have different water temperatures, water pressures and TDS we must also have a different restrictor to make up for those differences in conditions.

With the capillary tube you install it, measure your waste ratio then remove and trim its length according to the included directions so you get and exact 4:1 or whatever fits your conditions. In some areas if you have relatively low tap water TDS you can trim the restrictor for 3:1 and still get good membrane performance and life, others of us have higher TDS so must stick with 4:1 waste ratios.