Water quality in closed circuit heating system

Roohollah

Dear Members ,

I would like to take this opportunity to wish all of you very Happy new year and perfect start for the new year .


I was viewing the Buderus boiler's instructions that I faced a recommendation which was about water quality in Hydronics heating systems .They recommended that Salt bedding type Ionizer should not use to soften the make- up water to fill the heating systems which causes problems .In this case, i would like to request further information on the best water quality to replenish and fill traditional heating systems .( I mean Cast Iron boiler and metal pipes which are used in boiler room ) ?

Thank you in advance for your time and help,



Once more, Happy new year to you all ,



I look forward to receiving your replies ,


Sincerely,

Roohollah

Jamie Hall

Buderus is -- no surprise -- right. Any ion exchange type of water softener will raise the sodium level in the water (they exchange sodium from the salt, which doesn't cause for hardness, for the calcium from the hard water). This increases the corrosive effect of the water -- substantially. Unless your water is really hard -- rare, except in a few limestone or marble areas of the country -- I'd use plain old water, from before the softener.

SWEI

Do you have any kind of water analysis? Tap water is just fine in most cases, but there are specific conditions which may warrant intervention of one form or another.

Roohollah

Dear Mr.Hall ,

Thank you for your clear answer and time .As you stated above, The Calcium increases the corrosive effect of the water ,and here we have two alternatives to fill the traditional heating system.First is the Softened water by Ionizer and second is raw water from well source .The total hardness of the well water is 340 ppm and its PH is 7.2 and TDS is 562 ppm .Now, I would like to ask you which one is better to use for filling and replenishing the traditional heating systems which composes of Floor standing cast iron boiler and black metal pipes ?

Thank you for your support and help.Also, Happy new year to you all .


I look forward to hearing from you ,


Sincerely,
Roohollah

Roohollah

Dear Sir ,

As you asked about the water analysis , The project that we are about to install is just fill by Well water ,and its chemical specifications are as follows;

Total harness 340 ppm ,
TDS 562 ppm
PH 7.2

The project is situated in out skirts of Tehran and does not access to Tap water or city water .


Thank you for devoting the time to help me .Moreover, wishing you all friends very happy new year and wonderful holidays.


Yours Faithfully,

Roohollah

Roohollah

This is the current Boiler room in which we are about to replace it with the new one which must be piped in primary & Secondary piping .

SWEI

Those pipes look like they have been in some kind of corrosive atmosphere. Do you know what the cause was?

How much water is in the system overall? 340 PPM is roughly 20 GPG -- definitely on the hard side. Filling with RO or DI water would likely be my first choice, but it will be important to know how tight the system is before you make a decision on the autofill setup (if any) used. Sorbox?

hot_rod

DI or DM (deionized or demineralized) water would be best. RO water, left untreated is a bit too aggressive, very low Ph.

You can purchase filtered water from many water supplies or rent the equipment to filter the water you have on site. Professional window washers and portable car washers often have the equipment to filter water on their trucks.

Hydronic conditioners can be added to your fill water, these lock up hardness, buffer ph, provide a film layer and assure new metals are protected.

As Kurt mentioned the system needs to be 100% leak free.

Any conditioner you add will need to be tested occasionally and possibly boosted.

Take an hour and watch "Water Treatment Across the Pond" at the RPA website. Roger from Sorbox does a great job explaining how all the different components of water can cause problems in hydronic.

http://www.radiantprofessionalsalliance.org/pages/livewebinars.aspx

SWEI

RO water is 90-something percent (depending on the membrane, the source water, and the amount of regen) deionized anyway. Both can have low enough pH to cause issues https://en.wikipedia.org/wiki/Purified_water

We blend RO with tap water to net around 3 GPG or 50 PPM total hardness, then add a conditioner (at less than the "recommended" doses.)

hot_rod

Yes , you need to know the quality of the fill water, both before and after ANY treatment or purification. Blending could be a good option, adding a conditioner may be best, there is a lot to know and learn about water treatment for hydronic. There is no simple one fix for all.

I know they have gotten better, used to be it took 3 gallons to produce 1 gallon of RO water, slow and expensive compared to DI where it just runs thru the media at the correct flow rate.

I like the Euro approach where they run the fill water thru the media as it goes into the system, might as well start with good water and adjust for metals in the system as required. Sorbox is one type, I predict you will see more small DI systems soon. Maybe from Axiom or others that are involved in fill systems already?

Jeff Persons did a webinar on water quality, he fills all his hydronic and GEO system thru a DI unit that he rebeds as needer. It's large enough to give good fill flow rate. His is about the size of a medium sized softener tank.


https://www.youtube.com/watch?v=cJTmZ4uCHns&index=7&list=PLuuV0ELkYb5VE0I4evUZ30b5U78CRlRdg

Paul Pollets

I'd be re-filling with distilled water, if available. The system should have a pH between 8 and 9.5 and low electrolytic properties. pH boosters are available from Rhomar. Digital pH testers are very inexpensive and the digital electrolytic tester comes with a Sorbox, which I'd also recommend.

Roohollah

Dear members ,

I would first like to sincerely thank all of you for the above helpful and informative posts .Actually , this is the first time I seriously engage in Hydronic's fill water quality ;in fact, I am very newbie to this industry ,but more enthusiastic to learn more and put all them into practice .So, All your support and time are fully appreciated .

As one of our friends asked about the cause of those corrosive pipes , I shall say that the former boiler room was an open circuit system (open expansion tank on the roof ),and as the system connects to atmosphere it evaporates and than the float valve in open expansion tank replenishes the system with fresh water which consists of oxygen and impurities ,and also the other major problem with the above system was about the condition of boiler at the critical return temperature from Radiant floor heating system which caused condensation in side boiler's furnace and beneath of pipe's insulation .Moreover, the fill water to heating system was untreated water from Well and the worst scenario was that there were leakages from gates valves .



Now, we would like to mitigate the mentioned situation and that why we are replacing the boiler room with new one .but, our big concern is whether I shall be able to provide this customer with your brilliant suggestions due to lack of modern technologies and reliable treatment machines .We do our utmost to follow your infallible advice on how to fill heating system .



Once more, our heartfelt thanks to every of you who devote time to support us and teach us some lessons which never forget .



Yours Sincerely,
Roohollah

SWEI

Does the system hold pressure for days or weeks, or will it need continuous makeup water?

Do you have access to a reverse osmosis system, even a small one?

hot_rod

A lot of the water in Iran is already RO or FO, reverse or forward osmosis as that is the main method of desalinization.

Roohollah

Sir ,

The new heating system is installing based on Primary & Secondary piping , and our systems hold constant pressure i mean that they hardly ever show any decrease in static pressure .But, the former system which was an open expansion tank always refilling the system .hope I would cover your question clearly .

As your second question , Reverse Osmosis is available ,but I have never seen the one to be installed in Boiler room to provide pure water for Hydronic heating systems in our area . I think that I must use Ro or DI to fill the system with proper water which Total harness and electrical conductivity comply with International standards .


Once more, Thank to all of your for kind attention to my concern and great hospitality ,


Wishing to hear more from you ,


Sincerely,

Roohollah

Roohollah

Dear Friend,

Here, I mean Tehran ,the city water is drinkable at least in most parts of it ,but , the quality of water has been changed due to severe drought .Supply water organization ( the organization which is responsible to provide hygienic water for inhabitants ) has blended a noticeable percentage of Well water with city water for come years ,and this policy causes some problems such as high total hardness ,Alkalanity .For instance, many of home owners are using the domestic filtration system which installs in kitchen to provide pure water ,and as you stated ,the filtration system consists of five or six stages to deliver purer water just for drinking or making tea or coffee .The outskirts of Tehran ,which are located in mountainous area , have better accessibility to Spring water ,and they disinfect the water for drinking by boiling .The pH of the water is 7.2 and TDS is 230 ppm ,and the inside of those galvanized pipes for supply water is pretty clean with out any Calcium deposits .


Also, People in Tehran especially Up market district are always use bottled water .



I am sorry for the long post ,and hope I could explain it clearly .



Thank you for your comments and taking the time to write me .



Sincerely,

Roohollah

SWEI

Roohollah said:

Reverse Osmosis is available ,but I have never seen the one to be installed in Boiler room to provide pure water for Hydronic heating systems in our area . I think that I must use Ro or DI to fill the system with proper water which Total harness and electrical conductivity comply with International standards.

That is the approach I was suggesting. If the system is properly sealed it will lose less than 1% of its water volume per year. This can easily be supplied using an extra expansion tank -- see ME's Glycol PIG concept.

Roohollah

Dear Sir ,

I have tried to open the attached link ,but it did not work and the page was not found .I think the problem is with our system in our area which filtration has been proceed by our Gov.


I would like to request you to correct me whenever I am wrong .To be honest , I am new in this industry and I need your assistance and your valuable advice .


Thank you for your time and posts ,


Sincerely,
Roohollah