Need help Olympia Cremina hydraulics redesign

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
giboja

#1: Post by giboja »

Hi all

I am trying to fit anti vacuum valve along with new pressurestat to my old Cremina (1979).
To prevent water dripping on connectors I was thinking to put anti vacuum valve below new pressurestat just not sure if it is hydraulically correct??

JRising

#2: Post by JRising »

That will dribble on your countertop. Remember, once the anti-vac closes, all the air is out of the machine, the gas in there is water vapour. When it cools back down, the anti-vac will open and draw air back in that will rise through the heavier water vapour, the water vapour in that tube will condense back to water liquid and run downhill... Probably just barely enough to over-flow the copper cup.
Is there a way to put in a taller anti-vac with a barbed fitting on it so you can still have it high up but aim the spitting away from all electrical stuff with a silicone tube?

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NicoNYC

#3: Post by NicoNYC »

The new Cremina's have the vacuum breaker in the boiler cap, you can buy just the cap and it is a direct fit on older machines. https://www.cerinicoffee.com/products/o ... tic-100450

I'd think that where you intend to install it, the tube leading to the vacuum breaker will fill with steam which will condense to water and be trapped in the bottom of the U, waiting to be blown out next time. It will work but also fill the case with steam and water, the frames of those machines are prone to rusting.

User avatar
civ

#4: Post by civ »

Hello:
giboja wrote: ... trying to fit anti vacuum valve ...
An anti-vacuum valve has to be above the boiler's maximum water level.
It allows air to flow in (to avoid a vacuum) and as the boiler heats up, the steam pressure (which is always above the water line) seals it.

See: https://coffeetechniciansguild.org/blog ... um-breaker

Best,

CIV

giboja (original poster)

#5: Post by giboja (original poster) »

NicoNYC wrote:The new Cremina's have the vacuum breaker in the boiler cap, you can buy just the cap and it is a direct fit on older machines. https://www.cerinicoffee.com/products/o ... tic-100450

I'd think that where you intend to install it, the tube leading to the vacuum breaker will fill with steam which will condense to water and be trapped in the bottom of the U, waiting to be blown out next time. It will work but also fill the case with steam and water, the frames of those machines are prone to rusting.
New cap from Olympia is waaaay too expensive.

Originally, on that same position is pressurestat.
If that condensation occurs while cooling down, that tube and below will be filled with water?
Still would be functional but I find it unlikely.


giboja (original poster)

#6: Post by giboja (original poster) »

JRising wrote:That will dribble on your countertop. Remember, once the anti-vac closes, all the air is out of the machine, the gas in there is water vapour. When it cools back down, the anti-vac will open and draw air back in that will rise through the heavier water vapour, the water vapour in that tube will condense back to water liquid and run downhill... Probably just barely enough to over-flow the copper cup.
Is there a way to put in a taller anti-vac with a barbed fitting on it so you can still have it high up but aim the spitting away from all electrical stuff with a silicone tube?
Can't find barbed fitting vacuum breaker in this size locally but that will be best solution as NO water will come close to wires.

I find this solution on image below simpliest but not sure if valve will operate correctly rotated?
If I go with smaller cup socket will not fit inside for tightening..


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Jeff
Team HB

#7: Post by Jeff »

It really needs to be vertical. It's a gravity-operated valve. At an angle it may work when new, but get sticky as it gets dirty with use or deposits start to form.

I'd get one with a hose barb. Even with a cup, they spit and spatter all over. With a pressurestat right there, that's even worse.

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giboja (original poster)

#8: Post by giboja (original poster) » replying to Jeff »


So be it.

Thanks

JRising

#9: Post by JRising »

Would a second small hole through the top of the machine horrify you? You could have the anti-vac on a short extension vertical above that T-fitting if there were a hole in the top for it to breathe through,

giboja (original poster)

#10: Post by giboja (original poster) » replying to JRising »

Actually, I was thinking about making new top cover with opening for pressure gauge but as one have to open machine to adjust the pressure anyway pressure gauge can be inside indeed.

I think the boiler can be drilled and tapped to put fitting as well..... maybe?