I noticed in two different espresso machine that water pH level was increased by going through them (water in 7,1: water out 8.0).
Is this a normal process?
If yes, is the recommandation from SCAA for water pH 7 for water in or water out of the machine?
Thanks

Hi Martin, here is a link to my post that sounds like the same problem.
High pH in the boiler water, help please
I have not found the cause or solution yet. I haven't opened it up yet to look inside. What are you using for water treatment? In my Strega, because it's a HX the high pH is only in the steam boiler portion so it doesn't affect my shots.

Hello,
In one machine (direct plumbed) I am using a charcoal filter since the water hardness is very low and total TDS around 35 ppm.
In the other machine with tank, I use filtered water from a brita pot, total TDS around 50 ppm.
I am wondering if it is a normal phenomena but cannot find the information.
Regards

I have my theory...

I think the "problem" is caused by venting pressure out the steam wand. Unless you are replenishing the water in your boiler with fresh water, it will (over time) creep up as you steam milk; the more you steam, the faster the rise in pH. HX machines and double boilers shouldn't have this issue on the brew water but can/will on their steam boiler (steam portion of the boiler for HX).

If I drain my steam boiler, refill with fresh water, leave the machine on 24/7, and not touch the steam wand I see relatively no change in pH after days. However, if I do the same and steam for cappuccinos, I see it slowly rise. The amount of the rise depends on how much fresh water I pull into the boiler by using the hot water tap to warm cups, clean portafilters, etc.

Any other thoughts?

Hi Merle, I try to flush my boiler weekly but I have on one occaision flushed my boiler 2 or 3 times and then checked the pH from the water spout and found it obviously the same as my softened and filtered water coming in (7pH). This was in the evening and I left the machine off. The next morning after the machine was brought on by my timer, I took a sample and it measured 8-1/2 pH. WTF.

uscfroadie wrote:I have my theory...

I think the "problem" is caused by venting pressure out the steam wand. Unless you are replenishing the water in your boiler with fresh water, it will (over time) creep up as you steam milk; the more you steam, the faster the rise in pH. HX machines and double boilers shouldn't have this issue on the brew water but can/will on their steam boiler (steam portion of the boiler for HX).

If I drain my steam boiler, refill with fresh water, leave the machine on 24/7, and not touch the steam wand I see relatively no change in pH after days. However, if I do the same and steam for cappuccinos, I see it slowly rise. The amount of the rise depends on how much fresh water I pull into the boiler by using the hot water tap to warm cups, clean portafilters, etc.

Any other thoughts?

That is an interesting theory and could answer my questions.
Many thanks

The steam wand allows 0 TDS H2O to escape the system. Therefore the minerals which came inside the boiler with the water that just escaped the system through the steam wand remain inside and raise the TDS (therefore the PH of the water inside the boiler).

A simple example: if your steam boiler contains 1 liter of water which has 200 TDS and you vent during a day 0.5 liters through the steam wand you'll have that water replenished from the water tank/tap connection but still retain also those solids which came with those 0.5 liters (which were vented as 0 TDS steam). So at the end of the day you'll have inside the tank 1 liter of water which has 300 TDS.