Treatment (enamelling?) Of a balloon heat exchanger?

[Christophe]

Ah good question I will see immediately!

I seem to have seen a bolted plate ... I confirm or I confirm in a few moments.

[Christophe]

et


Good then, as we see on these 2 photos.

The bottom exchanger is easily removable (bolted plate, hence the zip pull on the cover see 2nd photo to the left of the vase) but at the top exchanger there is nothing at all (I did not remove the insulation by cons).

Strange isn't it?

[Cuicui]

Do you have 2 heat exchangers on your ball?

[Christophe]

Well, yes! It is an old enameled solar flask (on one side and not the right recess) with double exchangers. The friend who sold it to me just told me that it did not have a double enameling ... hence my corrosion problem in the long term ...

Looks like you didn't follow the editing ...

There are all plans here: https://www.econologie.com/forums/schema-cha ... t4266.html

[Chatham]

But chatam the exchanger is not enameled inside precisely ... hence my problem if it were there would be no problem

Ah, I understood the reverse: if it is "enamel" on the outside, it is only "enamel-like" paint (much less hard than real enamel)

You must already know what type of water you have: if it is limestone, it is a safe bet that the walls are already covered with a layer of limestone, which as everyone knows, crystallizes at ~ 65 ° C, so for the corrosion will be very slow, if it is acidic, then there ...
As far as I know there is an original sacrificial anode already at the exchanger ... At my parents who have a solar water heater (with electrical resistance for winter) for 30 years, the steel tank is origin, exterior appearance like new (hard water) ...
I see that you have a brass / copper / galvanized steel mix: watch these assemblies because sometimes the brass eats the galvanized in a very short time (I saw it myself: 2 fingers from a beautiful flood because the part threaded with a galvanized pipe in contact with brass had almost disappeared!)

[Cuicui]

Complicated your thing. Where is the DHW reserve?
If you ever add a plate heat exchanger, do not necessarily add a circulator, the secondary circuit can operate as a thermosyphon if the exchanger is lower than the tank.
I had two 2 liter flasks puffed up by corrosion. I understood the lesson and invested in a stainless steel with stainless steel exchanger too. Since then, I have been quiet.

[Christophe]

Complicated your thing. Where is the DHW reserve?

There is no need to reserve ECS, everything goes "direct".

Complicated no but "original" (or rather not banal) yes.

Don't you want to look at the diagram to please me please? See link above ...

You understand the interest of my montage ...

I had two 2 liter flasks puffed up by corrosion. I understood the lesson and invested in a stainless steel with stainless steel exchanger too. Since then, I have been quiet.

How long did it take to be "puffed" and on which parts?

[Christophe]

Ah, I understood the reverse: if it is "enamel" on the outside, it is only "enamel-like" paint (much less hard than real enamel)

Ben it is enamelled on the outside of the exchanger which is inside the tank ... DHW side in a NORMAL assembly but my assembly is REVERSE.

Look at the assembly diagram you will quickly understand!

https://www.econologie.com/forums/schema-cha ... t4266.html or directly: https://www.econologie.com/photo/montage ... e_bois.gif

You must already know what type of water you have: if it is limestone, it is a safe bet that the walls are already covered with a layer of limestone, which as everyone knows, crystallizes at ~ 65 ° C, so for the corrosion will be very slow, if it is acidic, then there ...

The tank is not in contact with the DHW ... and anyway it is enameled but only on one side apparently (not the right one in MY case)

For water I think it is neither (too) acid nor (too) limestone because:
a) the DHW tube that I cut to put the bypass was not at all scaled
b) it was also not at all "eaten away" by the acidity while the pros strongly advise against using copper for DHW ...

As far as I know there is an original sacrificial anode already at the exchanger ... At my parents who have a solar water heater (with electrical resistance for winter) for 30 years, the steel tank is origin, exterior appearance like new (hard water) ...

Does the exterior aspect matter little?
It must be the same type of gear, at the time there was no bcp manufacturer of solar (the ball dates from 1979).

There are 2 magnesium electrodes but as they are on the "heating" side now they are useless .... (I hope they will not do a "counter effect").

You can see one (finally its cap) in the alignment of the top exchanger about 15 cm.

I see that you have a brass / copper / galvanized steel mix: watch these assemblies because sometimes the brass eats the galvanized in a very short time (I saw it myself: 2 fingers from a beautiful flood because the part threaded with a galvanized pipe in contact with brass had almost disappeared!)

Damn I didn't know that ... but hey it's on the "heating" circuit so it's not very important if there is no more galva ... unless you are talking squarely about the complete tube and not only of the galva layer?

[Rabbit]

Ben my exchanger is steel ... I do not understand your idea of ​​putting copper on ... copper

The idea is not to put copper on copper but copper
on steel. Like galvanizing but cold and with
copper.

By the way the copper is deposited on the steel and the iron replaces the
copper. There is a way to explain this in a more academic way but
I leave this pleasure to others who are more intriguing and cleverer than me.

[Other]

Hello

Your steel heat exchanger on which side do you fear corrosion?

I suppose outside that in contact with water, the interior side you can put a liquid stabilized with an antioxidant as we use in cars with treated water.
the external side that in the balloon you will have a lot of difficulty in solving this problem, a good enamel lasts approximately 4 years and again you pick up with red water which contaminates your second tank,
A tank which is well made vitrified inside, lasts at most 15 years in water not too aggressive and provided that you change the large magnesium electrode to 10 years of use
the exchanger must be made of stainless steel or copper (in my case it is copper) External freon and internal sanitary water)

Andre