How do I identify defective TRV brand?

tplazer

Customer with overheating baseboard radiator, TRV is old & dead. No name at all on the control head unscrewed head off baseboard, no identification anywhere. I don't want to drain system to change main body, want to replace head.

SWEI

A photo or two would help.

tplazer

Here are a couple pictures

hot_rod

looks like an old Danfoss. Maybe remove the white plastic and find a brand underneath. Most brands use the same thread now a days.

Bill_17

The product in the photo is not from Danfoss, take a picture showing the end/face of the thermostatic operator's handle and another showing the side of the valve as there is often a logo on these items.