Louis wrote:Since I've got the S1 Vivaldi, I found myself using the hot water tap a lot more than what I was expecting (can provide as much as 1L), even if I understand that a $2000 machine is not to be used as a $10 kettle, that I will get more scale as more water is going through the steam boiler, etc. Instant hot water is practical and this is simply hard to ignore.

Hello!
Another Vivaldi user (and lover) here
I am hot water wand lover too!

Louis wrote:The only issue I have is that the process is very inefficient: ~110°C water coming out as some 100°C hot water along with a lot of steam. The water is also too hot for our main use: green tea. We cool it off to 75-80°C (~175°F) by moving it through two different vessels before infusion. Wasted electricity to heat water, wasted electricity for the air-conditioner to cool down the excess heat.

I, on contrary, am happy with the temperature: I drink a lot of straight hot water (of course I drink it a little bit colder then what's coming out of the wand) and I generally prefer it not mixed with water that is not boiled - for it is different animal then the boiled water. I also apply TCM (Traditional Chinese Medicine) to my food and cooking so this is another reason why I very much care.
I too prepare tea with the hot water wand but this is only for guests who are either non-demanding or ignorant about tea. Otherwise I use a kettle and dedicated tea-pots for brewing. If you have a good quality green tea, I recommend you have a go at brewing it properly - the result will be rewarding.

Cheers,
Pawel

mhoy wrote:Interesting project. You might be able to make the stack shorter by putting the one way valve along the bottom of the cold water pathway. This assumes you need the extra space, or that it simplifies the install.

Another option I have to reduce size of the setup is to use 1/4" inline check-valves (like these ones), getting rid of the 4x 1/4" to 3/8" adaptors and reducing the space needed by the full size 3/8" check valves but as I fear a check valve blockage, I'm not sure if I would do that, even if the LM GS/3 uses check valves similar to this (the LM GB/5 uses full size 3/8" check valves; GS/3 uses ¼" inline check valves mounted on the water mixer block). In fact, if the boiler side check valve was to stick open, with the hot water solenoid closed, water would flow from the mains to the steam boiler (through the faulty check valve), until it is full; if the vacuum breaker valve is open at that time, this would result in continuous water spillage inside the machine, on the counter, until my water leak detector kicks in to cut the mains... and the timer would later turn the machine on eventually... not good).

I might also add ¼" inline-filter-fittings, to ensure nothing from the mains (charcoal particle from the filter?) or from the steam boiler (scale particle) could block one of the check valves. This way:

• if the steam side filter gets blocked, I simply get cold/colder water from the hot water tap
• if the mains side filter gets blocked, I get boiling/hotter water from the hot water tap.

Either way, I would know and this would prevent risk of check valve blockage. I would still plan to verify the check valves at least one time a year, to ensure they are clean and seat properly.

...I might, after all, use ¼" inline check valves (as on the GS/3)...

Any opinion / advice on this?

mhoy wrote:Chris Coffee had teflon tubing for use with John Guest fittings that I used to plumb in my Elektra, likely has anything else you need too.

Mark, you are suggesting using JG fittings instead of threaded brass fittings in my setup? Can John Guest (polypropylene or acetal) fittings be used with ~110°C water?

The main question I still have to answer is on the threading type used in Italian espresso machines.

I now assume it is ¼" or 3/8" BSPT (BSPT [British Standard Pipe Tapered] male side, BSPT/BSPP [British Standard Pipe Parallel] female side). I also need to find where to source these.

I may in fact follow your advice and send my plan to Chris' techs and ask for their advice (to ensure I didn't miss something), confirm if they would not see this as unreasonable modification to a machine under warranty, and ask for the parts/pricing.

JohnB. wrote:When the front cover is fitted doesn't the pressure gauge & feed pipe take up about half of that space?

This is what I need to check. Else, it could end behind the steam boiler. From memory, I'm pretty sure I can find some empty space in the big Vivaldi frame, but I need to check for sure.

I hoped I could make some measurements yesterday but didn't have time to do so.

Louis wrote:Mark, you are suggesting using JG fittings instead of threaded brass fittings in my setup? Can John Guest (polypropylene or acetal) fittings be used with ~110°C water?

I'd ask the real experts at Chris's Coffee and/or HB before taking my advice on this. They are easy to work with, but I've no idea on it's pro-longed use at temperature. The insides of various vibe pump setups have Teflon tubes but from what little I've seen they are on the cold side.

You will be relying on the check valves to prevent a major problem. Anyone with real world experience on the failure rate of the check valves? As you've mentioned a filter would help but may also need periodic cleaning or a pristine water supply.

I'd personally keep it simple and add the cold water later from my faucet.

...then again this is HB, why not some overkill in the design. You could add a solenoid valve on the cold supply side and have it some how trigger when flow was detected on the faucet. (Or if your hot water is already solenoid based, add a cold water solenoid to the mix).

Mark

CoffeeOwl wrote:If you have a good quality green tea, I recommend you have a go at brewing it properly - the result will be rewarding.

Pawel, I have heard this argument many times, but in my experience water from my steam boiler is fine. I have taken many samples, letting them cool down and tasting them: they do taste as good as fresh filtered water.

All the water we now drink, either cold or heated in our kitchen boiler or the Vivaldi boiler, comes from an inline activated carbon filter under the sink.

I do use the steam boiler extensively, keeping its water fresh: some water to preheat cups, some to rinse the portafilter, some to preheat the Thermos bottle in which I bring tea to work and for tea itself. I also turn the steam boiler off right after my morning session, before if finishes refilling itself. When the machine turns itself on latter for supper, it fills in with fresh water. Note: this could cause damage to the heating element if it is not submerged as it is turned on, but this doesn't happen in my case as my Vivaldi is in 15A mode: the machine fills the steam boiler while only the coffee boiler heater turns on. When the steam boiler element kicks in, it is already filled in.

mhoy wrote:...then again this is HB, why not some overkill in the design. You could add a solenoid valve on the cold supply side and have it some how trigger when flow was detected on the faucet. (Or if your hot water is already solenoid based, add a cold water solenoid to the mix).Mark

This is pretty much how the Speedster is set up. Separate solenoids control the hot & cold water inlets to the mixing manifold with a jet restricting the cold water flow at the inlet.

mhoy wrote:...then again this is HB, why not some overkill in the design. You could add a solenoid valve on the cold supply side and have it some how trigger when flow was detected on the faucet. (Or if your hot water is already solenoid based, add a cold water solenoid to the mix).

I have thought about this too. It would in fact be easy, as all I would need to do is splice power from the Vivaldi hot water solenoid and connect it to this newly added cold water solenoid (right after the tee split from the pump inlet, or between the steam boiler and the mixing tee).

But you are right: this seems good on paper but would indeed be overkill and I don't want to go there in terms of complexity...!

Anyway, I do have a LeakController safety, with a detector sitting right under the machine. If something disastrous happens, I would only get some water splashed in the machine/counter before water is cut off. Then I would need to fear for other damage, with a machine on timer, with water cut off...

Version 2 of the plan.

I've made an update, using the smaller GS/3 check valves. I still need to add filters before the check valves and maybe a whole solenoid between the tee inlet and the new rig.