Boiler notes with CAP and solar

[dedeleco]

my boiler is able to heat water instantly

To my taste; yes, because your boiler has what power?
At least 15KW which is enough for a shower or bath with not gigantic flow.
Anyway, 60L is small and therefore you sometimes run out of your 60l quite quickly if "your boiler is able to heat water instantly" !! If this has never happened, she is capable of it for your personal use, not for 3 people filling a bath or a shower at the same time !!

The water arriving on the solar exchanger is already hot at the top of the tank, which puzzles me, because I would tend to send the cooler water from the bottom of the tank to heat it instead of recycling than the water from the top of the balloon which arrives from the bottom immediately goes back upwards !!

It would be good to make the diagram including the internal assembly of the boiler with 2 circulators!

[PITMIX]

Hello
Here it is done, I connected the pipes properly.
Now my boiler is connected as on the last diagram that I published. It is just before the hot water taps and is permanently supplied with preheated water from the 200L tank.
It is much more logical.
When you think about it, the boiler must necessarily make instant hot water because when you want to fill a 150L bath with hot water the 60L tank empties very quickly.
So I installed a pressure switch so that the boiler only starts when hot water is drawn and it works very well.
It only remains for me to modify my DHW and V3V thermostat so that they operate in differential mode in order to prevent the DHW from heating the solar panels (losses).

The diagram of my boiler is this:

[PITMIX]

Hello
Another p .... hs probe on the boiler.
This time it was the internal balloon probe in the boiler. I replaced it with an NTC probe and it works again.
I don't know what type of probe it was originally.
There is nothing written on the wire or on the head, to find out more I would have to open it.
For now the NTC probe does the trick so it will stay that way, but I tried to schunter / unshoot the probe and it works all or nothing.
This will allow me to connect my own thermostat (indestructible gas bulb) in place of the probe if I encounter a problem again.
Last night I provisionally reconnected the resistance of the electric balloon but I quickly realized that the resistance of 2200W is very thin to heat the entirety of the 260L of water circulating in the circuit.
I feel that one day or another I will install a solar tank and make me a hot water circuit by stratification because my circuit is very complex and requires a lot of energy even if it has a great autonomy.

[dedeleco]

It is necessary to measure the behavior and the temperatures of the balloon according to the resistance by putting a graduated potentiometer in place of the probe to have the characteristics of the hs probe then by turning it on different graduations !!
The resistance required is thus determined as a function of the desired temperature and thus one can have an idea of ​​the NTC probe necessary to replace the hs probe.
Also measure the voltage sent to the vacuum from the boiler on this probe and the short-circuit current.
It is important to have a pretty good probe because the balloon may boil (dangerous, explosive) or not to heat enough !!
I would double the safety probe that cuts the gas of this boiler to have more peace of mind in case of overheating and failure also of the safety sensor of this boiler with elements with low reliability !!

[PITMIX]

I found a website with the probe in question at € 7,9.
The electronic circuit is a Brahma, the site I found is Romanian.
The reliability problem is explained ...

http://www.e-boilere.ro/automatizari-bo ... ahma-st-07


I measured the temperature in the boiler flask with a thermocouple probe thermometer and I made my adjustment according to this measurement.
60 ° C and the boiler cuts in regulation.
The setting is identical to the original probe.

I checked the original probe to determine that it was a CNT. I think it has become false over time.

At 60 ° C it is at 350kOhm while the new NTC probe is at 1,5kOhm. Normal that the boiler does not start with such a value because I imagine that it read a water temperature equivalent to several hundred degrees.

[dedeleco]

This 5K thermistor at 25 ° C should work at 1,5 € in my opinion by soldering the end of the wire. Can be more reliable ??
http://www.conrad.fr/thermistance_ntc_t ... 224202_FAS
http://www1.produktinfo.conrad.com/date ... yp_M87.pdf

for a next breakdown !!

[PITMIX]

Thank you for the information. But the NTC probe that I installed corresponds exactly to the manufacturer's data and in addition it's free so I keep it.

I downloaded and translated the technical doc of the original probe, Brahma is an Italian brand. It confirms what I have seen many times in my profession, Italian electronic products are "biiiiiiip"

http://translate.googleusercontent.com/ ... 9rpxHhMCeA

[bobono]

I just got two free air water heat pumps, in good working condition, I haven't been able to test them yet, they work at R 22.

[PITMIX]

400V three-phase or mono 230V?
The R22 has not been on sale since the start of the year.
You will find regenerated R22 at a high price in the event of a leak.
Otherwise you will have to retrofit your PAC to R404A. Oil change, regulator, filter drier and replacement of seals.

[PITMIX]

Hello
From galley ensues ideas ...
Following the incident on my boiler (resolved), and the ineffectiveness of the electric balloon, in heating the 260L of circulating water, I dropped the hot water recirculation loop system, to which I was so attached .
In fact, I cannot combine solar efficiency and hot water recirculation with a single DHW pump.
I stopped the DHW recirculation pump and deleted the operating hours for the boiler.
Thus the boiler heats the small 60L tank by stratification as at the origin.
Cold water (7,7 ° C today) always supplies the 200L tank before going to the boiler. The water is therefore naturally preheated (17 ° C) by the ambient temperature of the house ... lol.

There were too many pressure drops and very variable hot water temperatures depending on the operating ranges of the boiler, which posed big problems for the small family.

By making a final modification of the DHW circuit (no offense to Madame ) I hope to obtain maximum comfort and efficiency (otherwise it will heat up for my registration number).
I intend to connect the solar exchanger and the DHW pump to cold water to make a preheating loop without going through the boiler and the taps.
The boiler supply will simply be drawn onto the preheating loop.
This solution is much closer to a standard solar DHW circuit.
Here is the diagram
https://www.econologie.info/share/partag ... G8qFQZ.JPG