Heater Return Valves: Hexagon Socket Adjustment, Unscrew Valve, Improve Radiator Flow

Buddy masiej2
I imagined it like this: you noticed that the radiators do not heat up with the entire surface, so you took action:
a) you have checked that the supply valves are open
b) you have bled the radiators
c) you have refilled the water in the central heating system
d) you have checked if the pump is working
e) you increased the pump power
f) you cleaned the pump filter
g) you fired properly in the boiler
Then you stated that if the above steps did not work, then there must be a flow, when shooting did not help, you wrote a request for help in restoring the circulation.

And now you're leaving with the text about the second stick, besides, you don't read the hint?

1 I posted you the cross-section of the return valve, it is clear from it that the maximum unscrewing of the hexagon socket cap under the cap gives 100% of the flow - so there is no sense in removing them completely, and it will deprive you of the possibility of disassembling the radiator.
2 When writing about jammed needles, I was thinking about the valves on the radiator supply, as you wrote, they have flow regulation (N and 1-7) - in this case, the return valves should be unscrewed with an Allen (left) so that the gland reaches about 2mm from the nut, and so left.
3 If your inlet valve needles are jammed, no action on the return valves makes any sense.
4 The basic prerequisite for proper heating is the correct amount of fuel in the boiler, I hope you understand that two anni three pieces of wood are not enough.
5 Seriously, I took it for granted that you know how to operate the boiler and that your request for help is the result of a malfunction. You insist that the flow is to blame, if this were the case, it would be one or two radiators, you also mentioned that after increasing the pump power, the ladder stops heating - these are signs of faulty installation or improper operation
I am trying to help you but I have no information and you act like you are sure about the flow and just need a nod to remove the glands from the valves and everyone else is writing nonsense.
I have over 20 years of experience in CO systems in the field of construction and service, if you want to use my knowledge, ask, if not, write me a beer.

Hello!
I will stick to the topic, because I have a small dilemma with the valve on the return (see photo) - namely the direction indicated by the arrow ... should it not be pointing in the opposite direction? Or maybe it doesn't matter?
I have a system with a pump, or even two, but the problem with this heater was from the very beginning.
greetings

Hello. This is a return radiator shut-off valve, maybe a mistake was made in the production, I often happened that the spring return valves have a badly reflected direction pattern, so now I always test them by blowing, but since the radiator is warm and everything is ok. take over.
Greetings.

Hello, close all supply valves, only leave the last radiator open. You will see if it will be completely warm. If so, the installation must be crimped. If it does not heat up the last radiator, you have to look for some limitation in the installation