To alleviate the concern over mold growing in the water container, a valid concern for sure, you could utilize smaller & easier to handle water container (2-3 gallons) and swap them out and cleanse them on a regular and frequent basis; 5-gallons typically lasts me about 7-10 days with my daily espresso making & steaming for 2 cappas and the occasional afternoon espresso.

Years ago, I did something similar where I used two 5-gallon carboys connected in parallel where the espresso machine would draw from one container and when empty I switched the flow over to the other container.

But, even using one-way valves apart of the aforementioned redundant system, I soon realized the system would lose prime and require a fair amount of my time to re-prime for the next container after I removed the empty/near empty container to allow cleaning & refilling.

The UV light idea might be a way of eliminating any mold potential but I would think it would need to be rigged up inside the water container? Interesting idea and curious to hear your results should you decide to go that direction.

A small 0.2um membrane vent filter like a Pall Acro 50 with barbed fittings would work to keep the tank from sucking in stuff, if you don't mind tapping threads into the plastic cap to screw in a barbed fitting to connect to the filter with a short piece of silicone tubing.

What is the danger of closing the hole in the lid to seal the system from air?

Sense the pump will do the work of sucking water from the container anyway.

Without a vent on any fluid system being pumped from a non-vented vessel it will create a vacuum...strain the pump into overheating/blowing a fuse or just not able to overcome vacuum to pump adequate volume of water.

How about these .25um filter stickers?

sticking one of these on the lid hole would be enough to keep the bad stuff in the air out?

https://www.amazon.com/gp/product/B08RS6QRK8/

Hopefully someone with more knowledge on this will chime in; however as I understand it bacteria range from 1-6um in size so the above linked filter paper that filters down to .25um should be good from that perspective.

FYI/FWIW, the plastic tank I have is somewhat rough in texture so not sure how effective the filter would seal.

Again, I'm a little bit obsessive when it comes to the espresso hobby, but what about adding an inline UV sterilizer somewhere along the line? I haven't figured out the best place to weave it into the set up, but it seems like something that would put my mind at ease and completely solve the issue (which may be completely non-existent anyway).

Also, don't order the 2 gallon stainless accumulator from rvpartscountry.com completely unresponsive and no actual humans work there apparently. Had to dispute the charge with the credit card company

https://www.freshwatersystems.com/produ ... q5EALw_wcB

Got all the pieces, minus the potential carbon filter and UV light.
I've never done anything quite in this realm of plumbing, so I'm going to walk through my assumed steps and ask for direction if anything sounds incorrect.
1) Cut tubing to length
2) Pressurize accumulator to 60 psi (equivalent to pump pressure-i hope this is correct)
3) wrap threaded ends with teflon and install
4) push fit tubing and connect entire system
5) close valve off 6 gallon tamco
6) fill tamco with water
7) place end of system in collection bucket to test flow
8 ) open valve
9) plug in pump (i have no idea if there an in between step for priming?)
10) adjust regulator to 40-50 psi
11) behold the magic

Does the accumulator or pump need to be mounted on something or can I just set them flat under the sink as the appear in the photo?

A couple of things:

You will want to hard mount the pump to the floor or wall of the cabinet, or as I did to a false wall. And I recommend using damping pads, easily sourced from Amazon, etc. Here's one: https://www.amazon.com/LBG-Products-Ant ... 220&sr=8-4

Search for "air compressor damping pads" for selection. The damping pads do help with vibration and noise. If you want to further reduce the pump noise you could add acoustic closed cell foam now or later, around the pump.

And you will also want to solidly fix the accumulator the same way although it doesn't need vibration damping pads.

The accumulator static pressure needs to be set for about the same pressure as the turn on/beginning pressure of the pump. I can't recall but I think I set mine to 30psi for my AquaTec pump and I might have left it alone with factory 20psi. If you charge it to 60psi, using my Aquatec 550 Series pump specs, this would be the maximum pressure the pump is designed to operate resulting in much work/stress on the pump, etc.

If this is your first go using Push-To-Connect fittings: Be sure to press the tubing all the way into the P2C fitting. You need to press the tubing in to the P2C fitting past the first "click" you feel. If you don't get the tubing all the way seated into the fitting...it will leak. Maybe, using a short piece of test tubing...give it a practice try to be sure you get it right. And it helps if you moisten the tube end with water before inserting into the fitting to reduce friction.

Lastly, I incorporated more tees and shut off valves to depressurize the system if you need to remove a component. Its not a big deal, just know if you need to remove/service something on the positive pressure side of the pump...it will be a little difficult removing the tubing from the P2C fitting as it will be pressurized. And, of course, you'll get a purge of water to clean up/deal with. Not a big deal but just an FYI.

Slayer has a "bleed the group" feature that makes it easier to purge the air bubble/vacuum...somehow that bubble of air needs to be released before water can fully fill the boiler(s) and group.

HTH.

Dan

spressomon wrote:A couple of things:

The accumulator static pressure needs to be set for about the same pressure as the turn on/beginning pressure of the pump. I can't recall but I think I set mine to 30psi for my AquaTec pump and I might have left it alone with factory 20psi. If you charge it to 60psi, using my Aquatec 550 Series pump specs, this would be the maximum pressure the pump is designed to operate resulting in much work/stress on the pump, etc.


Slayer has a "bleed the group" feature that makes it easier to purge the air bubble/vacuum...somehow that bubble of air needs to be released before water can fully fill the boiler(s) and group.

HTH.

Dan

Ok, I think I was looking at the pump max pressure, I'll try and figure out the pump turn on pressure.
I'm probably going to do the false shelf as well, and do the full pull drawer as long as I have enough space.
I have to look into how to purge the air bubble on start up for the GS3 MP when it gets here which could be soon.
Thanks for the info!