DANFOSS - The radiator heats all the time, the regulation of the head does not w

Hello, I have a problem that the knob in the head does not work in my radiator and therefore I cannot regulate the heating, and the radiator heats up all the time. And here is my question, is there any way to fix it without the help of a professional? Below he adds photos of the head.

A similar topic HERE

Everything is nice, but I'm a bit green in this topic and I would have to describe it in more detail.
"On the valve, around the pin that presses the head in, there is a profiled ring. If you look at it, you will notice stamped numbers on it. Pulling it towards you, you can adjust the flow by turning it."

So how exactly should I adjust it so that if I want it not to heat at all, I turn off the radiator and turn it up if I want.
I apologize in advance for the problems.

If the valve does not respond to the needle controlled by the thermostatic head, it means that: either it is seized, or something has come to the valve, some "rubbish" and the valve cannot close.

Valve for replacement (purging).

The orifice control only allows you to set the average maximum flow in the range of -100%.

He could have approached the valve with some rubbish (I also had it in the bathroom once and I have the same valves). You can remove the head, temporarily set the nub (maximum) to the increased flow to flush the valve, then restore the previous initial setting (cross banding) and install the head. There may also be another reason for this, namely a damaged thermostatic head, e.g. a broken metal bellows with gas in the head (as the temperature increases, the gas expands and pushes the plug which presses the needle and closes the valve, and when the temperature drops the gas contracts, and the plug retracts, reducing pressure on the needle). A head that is damaged in this way (pierced bellows) can only be replaced. You can check the head by observing the mushroom's reaction to temperature in it. For example (we do it on the removed head) we measure the distance from the plug to the edge of the nut. Then we put the head into the freezer and measure this distance again. After such a strong cooling (temperature in the freezer around -18 to -20 degrees, sometimes even colder) the difference should be significant.

Perhaps otherwise, it is enough to disassemble the thermostatic head and install a special knob (such a red nut) that allows you to manually close the valve. If the valve can be closed like this, it is functional, and only the thermostatic head is damaged, if not, as I wrote, the valve to be replaced.

Hello. I apologize in advance as it is possible that I should find the answer to my question above, but I am completely ignorant of plumbing. My problem is also that the heater is still hot and I can't turn it off. When I turn the head, it rotates around and in addition to the white knob, the black plastic rotates closer to the pipe. What can I do with it?
I am asking for help and understanding.

Ev ... there should be a nut below the head (ie closer to the pipe). Try to tighten it and stabilize the head position.
Then the regulation should start working.

If not, write.

It worked, thank you very much for your help.
Could it be repeated, e.g. because an element is well-made?

Ev... wrote:

It worked, thank you very much for your help.

Depending on how long the head was used with the play. But probably, if it worked, it will keep. You can of course try to tighten a little more, but don't go overboard. Because something else will break and there will be a meatball.

Hello,
I have this inquiry. The radiator stopped heating in the bathroom, in the block. It was slightly warm at the very top. I called the gentlemen from the administration. Bad luck that they came and it just happened to heat up on the whole, and decently. I described what was happening, they recommended to observe, in case it was cold again unscrew the thermostat. And so it happened. The radiator cold 95%, only the top slightly warm, I unscrewed the thermostat and in a flash hot. I thought the head damaged I will buy another, but also with this situation is similar. The radiator non-stop on 5, because exactly in our cooperative there are no dividers in the bathrooms. The temperature in the bathroom fluctuates between 20-22 degrees. I have a question in connection with this what is happening and what is responsible for such a situation, for any advice I will be grateful.

Is the valve properly installed (and also the head)? It may be that the head is located directly above the radiator, so it is heated by it and prematurely shuts off the supply of the heating medium (it interprets that the temperature in the bathroom is high, because the head is heated by the heat rising from the radiator). A lot would be explained by the photo. It may also be misaligned. Contrary to appearances, the position of the valve can be important.

Yes, the head is mounted above the radiator on the right side. The problem is that so far, and I've been living there for 10 years, everything was fine. I didn't change the position of the head, etc. I replaced it only once, 4 years ago, the old one cracked on the plastic part, maybe the temperature did its thing. But then a few years later everything worked until now. I was wondering whether perhaps during the recent frosts they circulated even hotter water and the head at the installation site heats up and cuts off the flow. Well, there is actually a hot thread there and it heats up itself. But that's just my musing. Thanks for your interest in the topic.

dzemes88 wrote:

Yes, the head is mounted above the radiator on the right side. The problem is that so far, and I`ve been living there for 10 years, everything was fine. I didn`t change the position of the head, etc. I replaced it only once, 4 years ago, the old one cracked on the plastic part, maybe the temperature did its thing. But then a few years later everything worked until now. I was wondering if perhaps during the recent frosts they had not circulated more hot water and the head at the installation site was heating up and cutting off the flow. Well, there is actually a hot thread there and it heats up itself. But that`s just my musing. Thanks for your interest in the topic

This hotter water probably causes the heat from the radiator to radiate so much onto the head that it chokes the water flow to the radiator. The head mounting is incorrect (but I don`t see it in the photo), because you have to remember that heat always goes up, so it heats the head directly. I would be able to comment more if there was a photo.
Unfortunately, valves are often installed incorrectly.

Zbigniew Rusek wrote:

dzemes88 wrote:

Yes, the head is mounted above the radiator on the right side. The problem is that so far, and I`ve been living there for 10 years, everything was fine. I didn`t change the position of the head, etc. I replaced it only once, 4 years ago, the old one cracked on the plastic part, maybe the temperature did its thing. But then a few years later everything worked until now. I was wondering whether perhaps during the recent frosts they circulated even hotter water and the head at the installation site heats up and cuts off the flow. Well, there is actually a hot thread there and it heats up itself. But that`s just my musing. Thanks for your interest in the topic

This hotter water probably causes the heat from the radiator to radiate onto the head so much that it chokes the water flow to the radiator. The head mounting is incorrect (but I don`t see it in the photo) because you have to remember that heat always goes up, so it heats the head directly. I would be able to comment more if there was a photo.
Unfortunately, valves are often installed incorrectly.

Too hot water (incorrectly selected parameters) causes cyclical closing and opening of the valve with characteristic knocking in the installation (the pipes cool down and after the radiator cools down, the valve opens and stresses occur in the cooled pipes due to uneven heating).