[Solved] Installation of SOLEI EKO-KWR 15 KW ELEKTROMET CO Boiler: Some Radiators Not Heating Up Properly

Hello,
I have a problem with the installation of what is at my home. Some radiators do not heat me up. The installation is not a new open gravity type. It is several dozen years old. Recently, I replaced the stove with a new one because the old one was already growing inside. I drew an approximate diagram of this installation:

Radiators that heat are marked in red, and those that are cold are marked in blue. The new furnace is a CO boiler with a water grate SOLEI EKO-KWR 15 KW ELEKTROMET. I am also sending a photo of connecting the stove to the installation:

I have no idea why these two heaters are not working. Certainly all the valves on the radiators are open, because after installing the stove and the first start-up, the upper parts of both radiators were barely lukewarm, then they stopped heating. I regularly allowed water to be installed once every 3 weeks for the so-called "trick". Previously, they also did not heat up with the old stove. The radiators are quite old, all cast iron. I am also sending the look of the radiator of one of the two that does not work together with the end of the overflow pipe and the photo above it of the pipes that enter the attic to the expansion tank and the pipe that goes to the other non-working radiator:

In case of doubt, I can send more photos or explain the unclear ones.

I am asking for help, because another winter is coming, and I would like the bathroom to be finally warm.
Regards Macros1111

Have you tried to vent them?

Do these heaters do not heat up at all, or do they hardly heat up at all? If the latter is the case, it is also necessary to distinguish between whether only the top of the radiator heats (poorly) and the middle and bottom are cold, or whether they heat (decently) the first two ribs and the remaining ones are cold. If only the top heats up and the radiator below is cold, it means that the water flow through the radiator is very weak, i.e. there may be a silted orifice, a twig overgrown with stone that supplies water to the radiator (or return), an incorrectly selected orifice (too small hole - through which is more easily silted). If the first 2 elements heat up and the rest of the radiator is cold, there is air in it. PS I do not consider high heaters at all, because they warm my head and the legs are cold.

Both of these radiators are cold. They don't heat up at all. In the diagram, I marked the blanked tube next to the tank. I unscrewed the cap and let the water flow in so that the water overflowed in that place. I also tried casing, i.e. screwed all the radiators on the ground floor, but it did not work. There is water in the tank, because when you move it, you can hear it splashing

If they are not air-tight, unscrew them and rinse, maybe the sludge has blocked the drain.

I think that the radiators are muddy, and besides, because they are radiators on the main riser, they had to be concealed quite significantly, and small passages can be easily blocked after many years.
All that's left for you to do is take off those radiators and correct (clean) the passages.
After the last time the water was drained and a new boiler was installed, a lot of the rust probably fell off inside.

Both of these radiators are cold. They don't heat up at all. In the diagram, I marked the blanked tube next to the tank. I unscrewed the cap and let the water flow in so that the water overflowed in that place. I also tried casing, i.e. screwed all the radiators on the ground floor, but it did not work. There is water in the tank, because when you move it, you can hear it splashing. Winter is not here yet and I will try to unscrew one of the radiators. We'll see if anything gets better.

This overflow bowl will come in handy for draining the sludge from the heater.

I think that if this heater is very dirty, the bowl may not be enough I remembered that in that heating season, when water was released, something happened that probably something happened, because the pressure indicator on the stove reached the end of the scale and wanted even more, and at one point I heard a loud gurgling, and a lot came out of the overflow pipe a lot of such black goo and the water ran down. After that, the pressure normalized.
First, I will try to unscrew the pipe that supplies the radiator with warm water, because there may be air in it. And I have to replace the bowl with a piece of tube that I will attach to the overflow so that the water flows directly to the grate in the floor and not to the tiles

It is worth remembering whether these radiators heated well before the failure, or only so hard (especially if the bottom were also warm - with high radiators it is more difficult to get a warm bottom). If they heated less than the others before the failure, it means that the flanges were too radical, so you need not only to clean the flanges, but also drill a hole a bit in these flanges (e.g. with a drill bit larger by 1 mm). A small passage causes - as previously mentioned - easy silting up of the orifices. One more thing. Were the valves in front of the radiator open to the maximum, or significantly and twisted before the failure. If they were significantly twisted, then in combination with an excessively small opening of the orifice, it could cause it to silt easily (the poor flow did not wash away the impurities from the opening). In general, old-style valves are shut-off by design, not regulating (the regulating ones are thermostatic).

Two years before the replacement of the stove, the radiator in the bathroom barely heated, only on the very top on two ribs. Later he stopped. The second heater in the room only half-full, and only for a day or two after adding water, then stopped. After installing the stove, all valves were opened to max. At least I think they were unscrewed, but they are very old and still have German inscriptions so I'm not sure if they unscrewed. The installation was then filled with water. Today is a cold day and I just lit the stove. The radiator in the room does not heat up to half temperature and will probably stop within a few hours, and in the bathroom it does not heat up as before

In the room, poor flow (I understand that half means from the top of the radiator to half) and in the bathroom - very weak. In the room, you probably need to clean the orifice or change to a larger diameter, in the bathroom - both clean and necessarily give a larger cross-section.

Hello
You added the pump now.
In which direction the differential valve flows, the valve may not close in that position.
Maybe rinse the installation, the filter will quickly clog.

In my opinion, connecting the boiler to be reworked. As for non-heating radiators, you will probably have to replace the supply valves. As far as I remember (it was a long time ago), I replaced such old valves with someone and they had a special orifice in the shape of a plate inside which you could move. Yes. It was in old communal blocks.

Traditionally, the rim was a brass plate with a drilled hole (he liked to silt if it was of very small caliber and the installation was stony). Old valves were also designed in such a way that by appropriate assembly (rotation) it was possible to set the passage to full, or - if the head was inserted incorrectly into the valve - it could be blocked at all. It was just that the head had something in the shape of a half-pipe at one end and by inserting it properly, it was possible to increase or decrease the flow (and these brass plates were given anyway - they were essential cross-banding).

"In my opinion, the connection of the boiler to be reworked." @gersik and what is wrong with the boiler connection?
At the end of the week, I'll unscrew both radiators and clean them. If it is necessary, I will insert new valves and see if it does anything.
@ drinking194 I do not know about it and I do not know which way what flows. I hired a specialist who connected the boiler and pump, and in addition, a second man from the electrometers came to check the correctness of the connection and made the first ignition and raised the warranty.

Due to the differential valve. It may not close completely in this position and the pump mixes over and over. The filter should be facing down. Tell me why did you install the pump on the return? Was it a requirement of the man from the electrometre that received the boiler.

Hello.
I feel sorry for my colleague to unscrew these radiators, but what is not done for the heat, a good key and forward
As for the pump, my colleague Gersik is right to remake it, unless there is no space on the power supply and the system will work due to gravity in the event of a power failure, maybe take a photo of the pipes above the furnace.
I have a question, when you turn on the pump in 3 gear, you hear the water flowing in the radiators, the filter when you cleaned it.
You have warm water from the reservoir or the thermal bath.

I also think that in this system, the pump will charge with all its power equally to the boiler and to the three-way valve and thus will interfere with its operation.

Probably too late, but maybe someone will need it.
I have marked in brown the lines that are not needed.



According to your installation, hot water flows to the sides and upwards (through the center line). Most flow through the side heaters, but some want to continue upward. Because he wants to go on, he wants to go somewhere. In our case, he wants to come back with the red center line. Hot water, on the other hand, wants to flow vertically upwards from the stove, which probably has a greater pushing force, so that it flows through the radiator in the hall. However, it does not want to flow to the cold ones, because it is blocked by warm water flowing from above. There is a stagnation.
In order to eliminate this situation, you need to cut off the lines that I marked in brown. Then the water will flow through all the radiators. Knowing that the water is flowing where there is least resistance, you may have to play around trimming the pit after removing the pipes. However, it may not be necessary.
Hope everyone understood what I mean.

Cutting off the lines in brown may eliminate the problem, but it has something to do with it. Namely, air vents will be necessary on the risers on the sides of the installation (it would also be recommended on the radiators themselves). Air vents on the risers are installed after cutting the supply pipe so that it is above the branch supplying the radiator on the top floor. You can give it automatic. Since we are talking about the modification of the installation, it would be worth taking care of this "double" radiator in the room (it looks like 2 radiators connected in series in the diagram). It should be done in such a way that each of them has an independent supply and return, because then it will be possible, for example, to heat the room with one radiator (when 2 give too much heat). With the solution shown in the picture, closing the valve turns off both heaters. You simply need to add a supply and return twig (and a valve) to the second radiator in the room - then you can think about reducing the diameter of the twigs supplying the first radiator because they are probably of large diameter (supplying 2 radiators at a time).

It was enough to unscrew and rinse the radiators from the trail

Flushing the radiators from the trail.