Termoc Ecocondens 25 Gold Combi Oven - Error L3, Rapid Temp Increase to 60°C, Cooling Issue

Hello, I am asking for help.
Termoc Ecocondens Gold 25 combi oven with closed combustion chamber.
Underfloor heating downstairs and radiators upstairs. The boiler has been in use for 2 years. From a few days after setting the central heating temperature on the stove 50 ° C, the temperature increases gradually in about 4 minutes to 60 ° C. The stove switches off and the message L3 appears.

After 3 minutes it starts again from 50 ° C to 60 ° C over and over again. The instructions show that the oven is cooling. The filter, venting, pump and radiators were cleaned. The stove is still under warranty, but a service technician from Termet claims that the stove works normally and can do nothing. I will be grateful to all experienced users for help,

Yes, I know this is not an error, but a message. But why does the temperature rise to 60 ° C so fast? And why did it remain stable before?

You know best because it's your installation.
Since the temperature rises quickly and the boiler itself is functional, it means that somewhere you have a blocked flow of water.
The lock can be in the installation or on the boiler itself. Maybe you have a valve closed somewhere, etc. etc.

I do not know Termet but I am wondering that the boiler is supposedly set to 50 degrees for the circuit, and yet within 4 minutes heats the water to 60 degrees. As for me, this is a malfunction in the boiler, because it should turn off after reaching 50 degrees.
Unless it is a matter of settings and these 50 degrees does not mean 50 degrees on the power supply, but maybe on the return, etc. Read the service manual carefully, maybe there you will find the necessary tips.
Added after 11 [hours] 53 [minutes]:
In the service manual on page 6 in chapter 2.4 you have a nice description of how the boiler works.
The boiler switches on if the heating water temperature is 5 degrees lower than the set value and the room regulator gives a heating signal.
It follows that if the boiler for the central heating circuit is set to 50 degrees, the boiler will turn on when the water temperature on the boiler will have a maximum of 45 degrees and the room regulator will give a heating signal.
Therefore, the working boiler after setting 50 degrees for what can heat water 45-60 water, not as you wrote 50-60.

In turn, the boiler turns off when the room regulator gives a heating stop signal or when the heating water temperature exceeds the set temperature by the hysteresis value (5 degrees by default), which you set in the range of 0-10 degrees under the code P.20 and then appears on the L3 display .
Your description shows that the hysteresis (P.20) is set to a maximum of 10 degrees, hence the heating to 60 degrees despite the set 50 on the boiler.
Under the P.25 code you set the L3 blocking time (by default 3 minutes), in the range of 1-60 minutes.
Restarting the boiler after a break caused by turning off the heating by the room regulator occurs when the regulator gives a heating signal and the water on the boiler will have a maximum of 45 degrees.
The boiler will be switched on again after entering the L3 blockade as above with the room regulator and additionally after the L3 blocking time set in P.25 has elapsed.

Having this knowledge and knowing the characteristics of your installation, you can adjust the length of breaks between individual burner connections in the boiler.
If the house is mostly heated and the thermostatic valves could cut off most of the heat consumers, then the boiler produces heat in an amount that other heat consumers cannot transfer to the environment, which results in an increase in the boiler temperature. Then it would be useful to extend the L3 break time, although a 20kW model with lower minimum power but at the expense of lower DHW performance would be a better solution
You will know best if you have heat or cold, or if the thermostatic heads have closed valves, etc. If you don't get it, ask a friend, as a last resort call the installer who did the whole installation for you.

Thank you very much for your comprehensive reply. She helped me a lot and explained. One more question should you really heat according to the factory settings 45-60 at 50 degrees or 45 - 50? I can't understand it too much.

BUCKS wrote:

although a better solution would be a 20kW model with less minimal power but at the expense of lower efficiency for domestic hot water

I was wrong, because Gold 20 and 25kW catalogs have the same minimum power, i.e. 3.0kW for 50/30 temperature.
Only a small note. Considering the given gas flows for a minimum power of 3kW, there is a difference of 1.1 l / min between both models.
Assuming that both boilers would heat nonstop at the same minimum power, gas consumption will differ by 66 l / h, 1584 l / 24h, i.e. about 1.5 m3 per day in favor of the 20kW model.

Maxdenon wrote:

should it really heat according to factory settings 45-60 at 50 degrees or 45 - 50? I can't understand it too much.

By default, the hysteresis in the boiler settings (code P.20) according to the instructions is 5 degrees, i.e. after setting 50 degrees for every boiler will turn off when it reaches 55 degrees and then it will go into L3 blocking mode.
In other words, the factory settings after setting 50 degrees, the boiler will heat 45-55, unless heating does not turn off the room regulator.
If you heat up to 60 I think that you must have hysteresis set to 10 degrees, so you should heat 45-60.
If you want the boiler to heat 45-50 then set the hysteresis to 0.
You set and check the hysteresis value in the boiler MENU as described in the service manual.
When browsing MENU in the Termet service mode, remember that after changing a value, even a random one, you do not need to confirm it, but this new value is automatically saved after a few seconds.

Hello.
For me, also in the Ecocondens Gold 25 combi boiler after heating the house, L3 appears and can be used every day for 3 minutes. Is it possible to extend the time intervals or L3 blocking time?

L3 blocking time by default is 3 minutes but the range of change is 1-60 minutes. Download the installation instructions for service and read.
If the boiler reaches the set temperature too quickly, you can also try to set it higher, because maybe you set it too low, and the boiler reaches it very quickly, despite the minimum power of 3.0kW.
Do you have a room regulator?

First:
the boiler power should be limited to the minimum necessary for the needs, depending on the heated surface.
The boiler cannot start at full power, it must work constantly with reduced power.
Only then can you keep trying.

best regards

irus.m wrote:

First:
the boiler power should be limited to the minimum necessary for the needs, depending on the heated surface.
The boiler cannot start at full power, it must work constantly with reduced power.

Only this is probably the responsibility of the service technician making the so-called first start of the boiler, not on the user's side.
Recently, I saw a brand new condensing boiler fired by an authorized service technician.
The pump left at the factory maximum, which resulted in high noise in the installation and maximum power for every "twisted" from the factory 24 to 19kW.
In addition, bearing in mind a few posts from the forum, which showed that service technicians also left high maximum powers, you get the impression that service technicians are in some part handicapped people who, although they have authorization, behave like amateurs or people intentionally acting to the detriment of their client .

Who will pay for the second arrival of a service technician as one radiator will heat poorly in a large installation? The electronic pump is factory set to max. At the customer's request to reduce. Nobody has a glass ball, and the customer usually doesn't know how many floorplaces he has. Is it with an additional pump, mercury or just a boiler pump. Even what exactly the radiator circuit looks like and how many there are ...

Who calculates the demand for CO and CWU of the building and presents it to the service technician at start-up so that he can adapt the boiler to this? Who will pay for the re-arrival as the max power will be too low at -10 degrees Celsius and an uninsulated cottage and wooden windows?

They do not pay service technicians to start the boiler so well that they spend half a day there analyzing the entire installation.
I do not defend service technicians, but think sometimes, and you do not make posts and accuse everyone.

L3 is not a mistake !! This information that the heating has ended and the main exchanger is cooled because the set temperature has been reached. Bucks explained well.

bro2004 wrote:

Who will pay for the second arrival of a service technician as one radiator will heat poorly in a large installation?

In this example it was about 70m2 to heat, without any flooring, only ordinary steel plate radiators.
A typical installation from a few years ago, so nothing unusual.

bro2004 wrote:

Who calculates the demand for CO and CWU of the building and presents it to the service technician at start-up so that he can adapt the boiler to this? Who will pay for the re-arrival as the max power will be too low at -10 degrees Celsius and an uninsulated cottage and wooden windows?

As I mentioned for a 70m2 premises with plastic windows, but in an uninsulated building, even if there were wooden windows, no normal residential building would have a demand of 19000W / 70m2 = 271W / m2.
I understand that it is impossible to set it perfectly but let's not make eggs, although the forum had descriptions from which it appeared that the service technician left 100% of the rated power for the factory.

bro2004 wrote:

They do not pay service technicians to start the boiler so well that they spend half a day there analyzing the entire installation.

I understand that for some service technicians it is better to take e.g. 271W / m2, because then there will certainly be no complaints from the customer about the lack of power, even in the winter of the millennium.
As an amateur, I see a great exaggeration, why doesn't the supposed professional see it.
I don't see any reasonable explanation for such a service technician here, except his passion for high power and over-inflating the power by at least 2 times

bro2004 wrote:

I do not defend service technicians, but think sometimes, and you do not make posts and accuse everyone.

Posting is the last thing I mean in this forum.
I blame everyone, who and where?
If you're doing a shoddy job and now you feel the addressee of my post, it's your problem, not mine.
I noticed a thing that does not require a lot of work, and yet you get the impression that some servicemen is beyond that.

You are accusing me now because you are telling me that I set up the boiler. That's why I think it's a shame to discuss with you. I have already found out more about other topics.

BUCKS wrote:

irus.m wrote:

First:
the boiler power should be limited to the minimum necessary for the needs, depending on the heated surface.
The boiler cannot start at full power, it must work constantly with reduced power.

Only this is probably the responsibility of the service technician making the so-called first start of the boiler, not on the user's side.
Recently, I saw a brand new condensing boiler fired by an authorized service technician.
The pump left at the factory maximum, which resulted in high noise in the installation and maximum power for every "twisted" from the factory 24 to 19kW.
In addition, bearing in mind a few posts from the forum, which showed that service technicians also left high maximum powers, you get the impression that service technicians are in some part handicapped people who, although they have authorization, behave like amateurs or people intentionally acting to the detriment of their client .

You usually troll.
You insult me and many of my fellow technicians.
You cultivate epic creativity of miserable flights in the technical department with mediocre substantive preparation.
Something did not work out in your life ?.

best regards

bro2004 wrote:

You are accusing me now because you are telling me that I set up the boiler

I don't say anything because I wrote "if".
And since you have reacted so emotionally to my general statement that service technicians tend to set up the boilers at the first start, you may feel the recipient of this statement.

irus.m wrote:

You usually troll.
You insult me and many of my fellow technicians.

I have not offended you anywhere, I respect your knowledge and willingness to help users.
I expressed my opinion, because more and more threads suggesting that the boiler has too much maximum power, in my opinion, it is usually not the fault of the users but the service technicians themselves who set it up.
It would be worth paying attention to it, and not as a professional solidarity pretend that everything is OK and sweep the problem under the rug.
After reading, among others, this thread, you can see that it is Kowalski who must set up the boiler properly, because he can hardly expect it from a professional. The problem is that not everyone Kowalski has a predisposition to configure technical devices such as a boiler.

Something seems to me that the topic relates to the message L3 Oven you have working is not a mistake. It is simply information that the stove has already warmed up the water and now distributes it and after cooling it is to turn on again to heat and stop all this again.

The problem of overheating the set value was done at home, I have ececondens gold plus 25. After installing the furnace, the operating temperature could be set on the furnace of 40 C and the furnace kept the temperature nicely and stable, after a month of work did not want to maintain 40C and overheating to 43C 99% pump efficiency. After three months it was necessary to set 48C for the stove to work stably without overheating the setpoint. And here is part of the truth that service technicians go to the easy way, either out of ignorance or laziness, because the first I called stated that you need to raise the temperature on the stove to 50C. But there are and wise service technicians, upon arrival of such it was stated that the furnace DOES NOT GO FROM 3KW MINIMUM POWER. Only up to 4.5KW and because the radiators I have not installed a lot they were not able to give up heat. After adjusting the furnace, the operation returned to stable from 40 ° C. I recommend to everyone with this problem to measure gas consumption on the gas meter when the furnace enters the minimum power. It should be about 6 liters per minute, I had over 8l.
The estimated amount of gas consumed in liters in 30 seconds is the instantaneous boiler output.