Waterguy RO Rebuild

[SSJaneczek]

Hello everyone. Been lurking as a new member for a while, reading TONS of posts on TONS of topics. This place is an incredible source of information.

Anyway, I just recently got a hold of a used Waterguy 2400 RO unit. Price was right, but the previous owner had it sitting for a couple years and was incredibly dirty. Other than that it's in pretty good shape. I don't have a lot of history on it, but I do have the Waterguy serial number, and what I think what might be a manufacture date on the HP hose out of the multistage pump. I'll try and post pictures of each at the bottom of the post, maybe someone can help me with a date of manufacture.
So far it's cleaned up real nice and looks practically new, especially after I polished up the stainless RO housing.
I've read about how to rinse/wash with acids and bases, but from what I understand that's generally for the health of the membrane, though I'm sure it does the hoses and pumps well, too.
I would like to give the inside of this thing a good rinse without a membrane, and while I have it apart, was thinking of hooking up the feed bump to the RO housing and running some PBW (powdered brewer's wash) through the housing and remaining hoses and capillary's. Anyone know of any issues with this?
Also, each of the end caps of the RO housing seem to have two grooves in them. It almost looks like there should be o-rings there, where the caps contact the ss housing. Am I missing o-rings? (pic below).
Thanks in advance!
-scott

[halladaymaple]

Definitely missing the orings. There should be 2 per cap. Good luck with the refurb. A good looking unit

[NH Maplemaker]

It looks to me that the orings are by your thumb in the picture ! The big grove at the top of the cap are for the clamp to connect to the housing.

[SSJaneczek]

I can see where it would look like the the o-rings are present, but they are not. What you're seeing is the groove returning around the back side of the cap. It's an illusion for sure.
I am aware that the top groove is where the clamp connects it to the housing.

Halladaymaple - thanks. Looks like they're $1.99/ea from Fresh Water Systems.
Think I'll hold off on purchasing them for now, until I get into it further and see what else I might need.
Might as well get a replacement o-ring for the pre-filter while I'm at it.

[SugarHill]

There should be 2 smaller o-rings on the inside of the cap, make sure those are there as well. These o-rings seal the end cap to the stub on the end of the membrane itself. Fresh water systems sell those as well.