Elektromet WJ-80 Solei Boiler (2014): Identifying Heater Type for Efficient Heating Performance

It seems that in my boiler Elektromet WJ-80 Solei the heater is on. At present, it's still warming but it's terribly slow. I would like to ask what kind of heater is there to find something like this, the year of production of the boiler is 2014.

greetings

Hello

Here is a little more about them (dependent on fixing).

www.elektromet.pl/pl/technika-grzewcza/productgetfile/1398

I do not want to advertise to anyone, but you can easily find it in the "g" search engine.

He proposes to open and see what is happening. For me, in the company after about 1.5 years of use (another boiler of horizontal assembly) there was no more anode, and the stone was so much that the shock.

The heater was working, but it was so overwhelming that the shock (end user of the water supply system). As a result, the set was replaced for peace.

greetings

There is no information about the heater in the file. For me, the heater is mounted on such a cap probably 5/4. The voltage to the heater comes, but when measuring the heater shows nonsense. Somewhere in the auction I met such a heater with an anode but I have no idea if it will pass (no information that is sitting in me) and I would not want it to be found to be different.
This is more or less the bottom line:

The heater replaced with the safety valve (I have not mentioned the anode because it has not been so damaged yet). I would like to ask if the cross-section of the connecting hoses matters? I ask because earlier I had snakes in blue-red stripes and now all silver ones with a smaller cross-section.