I repaired a couple of CH radiator valves the other day.
The radiator in my son's room was stone cold despite the thermostat valve set to high.
I detached the thermostat valve to reveal the valve pin. I pressed and pulled it but it would not move.
I was planning to have the valve body replaced, then I chanced upon a tip to oil the pin or hit the body (not the pin!) with a hammer.
I gave it a tiny droplet of oil and it popped right out within a second! Working again
Then one of two big radiators in the living room was cold too. but the (non-thermostat) valve knob was non-removable... I tried squirting lock spray under the head to lube the valve pin, if it chanced to reach there. No dice.
I gently tapped the valve body from below with a hammer and immediately the radiator started to warm up!
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2011 Honda Insight + HID, LEDs, tiny PV panel, extra brake pad return springs, neutral wheel alignment, 44/42 PSI (air), PHEV light (inop), tightened wheel nut.
lifetime FE over 0.2 Gigameter or 0.13 Megamile.
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