water pH level for Viessmann Vitola Boilers

R.Bell

Can you tell me what the correct pH level of the water in a Viessmann Vitola Boilers should be I am presently at 8.5 but have been told that is low and I should be at around 10 to 10.5. Also what is the best additive to add to achieve the higher level of pH if that is where I should be.

Mark Eatherton

Check with the manufacturer for sure...

But in my experience, the typical acceptable pH range is from 7.6 (neutral) to 8.5. Anything above that is considered reserve alkalinity, to compensate should acids be formed in the system.



The only thing that can generate acids in a closed loop heating system that I am aware of are glycols. If oxidized, they break down into glycolic acids, and will lower the pH to the point that excessive corrosion will occur on the ferrous metals.



These rules of thumb are applicable to system with ferrous components only. If you have an aluminum black boiler, you have to comply to a completely different set of standards.



ME



PS, I am not a water chemical expert. If in doubt, call Dwight at Rhomar Water technologies. HE is a water management expert.



ME

Jean-David Beyer

If you have an aluminum black boiler, ...

I have a boiler with an aluminum heat exchanger (W-M Ultra 3). The rules are not that different.



pH between 7.0 and 8.5

Hardness less than 7 grains

Chlorine concentration less than 200 ppm



With aluminum, you do not want pH too high, or the aluminum will dissolve.



PS, I am not a water chemical expert. I am not even a heating professional.

meplumber

The Vitola is not aluminum.

The Vitola is a biferral heat exchanger, meaning that the laminate the two different types of cast together to create a more forgiving block. 



I normally look for pH in the 7.0 to 8.0 range.  In a closed loop system unless your pH is way out of whack.  below 6.5 or above 8.5.  The water will become "dead" after a while. 



I agree with Mark.  Check with Viessmann.  Their tech support has always been good to me.

R.Bell

pH Level for Vitola

I already checked with Viessmann their official response is as long as the water is good enough to drink it is okay to put it in the boiler. A very disappointing response I thought for Viessmann, will check with Viessmann in Europe  cannot believe they would not have a recommended pH level as that will make or break a boiler system

zacmobile

ph

From what I understand the ph in closed loop heating systems needs to be between 9-10, steel supposedly is happiest there, and aluminum likes it a little lower.



here is a good article in the Modern Hydronics magazine from HPAC mag(scroll down to page 39)



http://www.hpacmag.mercuryemail.com/archives/supplements/Modern%20Hydronics.pdf

R.Bell

pH Level

Information I got from Viessmann out of Europe says they like a pH level of 8,5 to 9,3 max.

They are more concerned about the hardness of the water than the pH level.



As I mentioned Viessmann North America will not give you a recommended level just has to be potable water.



Thank you all that posted your input and especially to zacmobile for his input and the link to the article very interesting reading which also addresses water hardness along with pH level as well as other interesting reading.



Seems to be an issue the boiler manufacturers should be getting on board to providing values or dealing with. As concrete info. seems to be lacking.



Hope this info. may help someone else down the road who needs an answer/guidance to the same question.

CMadatMe

PH Level

PH Level changes once water is heated and generally will be in the range given by Eurpoe. The reason you recevied the potable water anwser is the boiler doesn't  care about low ph due to the boiler being 316 Ti Stainless (condensing boiler heat exchangers see PH's of about 4 of even less) sandwiched with cast iron



You were better off calling the local Viessmann Rep than RI because you were probably just forwarded to the call center in Canada. You can look up the local rep via the link.

http://www.viessmann-us.com/en/service/kontakt/Sales_Network/US.html



Reps are traditionally the application points of contact for Viessmann not RI or Canada.