After a few months I have finally decided to do something about our heating system which is still showing some pressure loss as I was mentioning already in this previous post.
Past week I asked the plumber company Gino Lepori & figlio SA to pass by and have a look at our expansion vessel (not too sure this is the correct English name) and check it thoroughly. I wasn’t at home to check if he really did it, I’m pretty sure he didn’t like the idea of troubleshooting the whole heating installation as it is pretty big. Still, he told me has checked that expansion vessel and that in his opinion it is still working properly. Therefore he called Elco on my behalf. On Wednesday current week their technician passed by.
Apparently, my burner, belongs to the first ones that were installed and are known for a faulty heater exchanger: if this is the case it is not possible to spot the water spilling out of the burner or leaving tracks somewhere, because the water would go from the heater exchanger where the condensed water therefore there won’t be any chance of noticing it.
What to do?
The plan is following: we will try to separate the water circuit of the burner from the circuit of the floor heating. By doing this we hope to see if the burner looses water pressure. And it should happen quite quickly, as the volume of water contained in the burner is a lot less from that one in the whole heating circuit.
Claudio showed me the steps that I should perform in order to separate the burner circuit from the rest.
Step by step guide: how to isolate the burner water circuit
Turning off the burner
On the right of the burner there is an On/Off switch. Just press it
Closing the pipes bringing water to the burner
There are 4 valves which are very hard to turn. I used some hard surface to protect my fingers while trying to move them in the right direction.

The valve in middle in yellow color, is the one bringing the gas and doesn’t need to be closed.
Once the water cannot reach the burner, in order to avoid the water pump of the burner to run while empty, it is a good idea to disconnect it.
Disconnecting the water pump
In the burner itself there is the pump which is connected to the power: it is sufficient to remove the cable in order to interrupt the power supply.

Once those operations are completed it is possible to start the burner again and check how the water pressure behaves. Shouldn’t there be any issue it should remain unchanged.
This morning: the first test
I decided to perform the first test this morning before leaving for work, around 08:15. As I entered the room I realized that the burner was running: I checked on the display and apparently it was heating. Also the valve for the heating was on. I mean we are in June, the heating is turned off, why did it start? It is true that in these days it is raining a lot, temperature have dropped, but outside there still are like 15°C while inside we still have a lot of warmth, still from the passed days, which were really hot. Anyhow, this will be next issue to be checked. I decided to do what I was told, therefore I executed each step as described above.
… and the first results
Which I don’t believe too much. The burner acted strangely, maybe because it had been heating until that moment. Anyhow, as soon as I had separated it from the rest of the heating circuit, the pressure dropped reaching very quickly 0.

Strange behaviour
The burner didn’t act like that when I tried together with Claudio, the Elco technician: in that case the pressure was stable at 1.6 bar. I guess that this happened because at the time it wasn’t heating.
What’s next?
I’m going to set the burner back to normality and try again. Meanwhile I’ll notify Claudio and see what he thinks about it. I believe that already the first, sudden pressure drop is already something which is showing a problem.