Well the first problem is the flow pipe (carrying the hottest water from the boiler) is directly underneath the thermostatic head. This will cause the sensing capsule to turn off the valve prematurely as it will detect the rising heat from the pipe and not the surrounding air.
PTFE tape all over the threads looks a mess. Use a small dab of sealant (eg Hawk White) on the threads to help reduce friction and a thin smear around the olive.
The compresion joints are not attractive - this radiator is under the bay window of the living room - use soldered fittings.
The pipework is a mess - it should pop up through the floor - but the lazy owner ran it around the skirting where he tee'd off the other radiator (with pushfit fittings!)
Ensure the radiator is 120-150mm above the floor - they rely on convection currents to give off heat. Too close to the floor reduces the convection effect. Despite their name radiators give off most of their heat by convection not radiation.
Since the radiator is fitted with a thermostatic head at one end the other end should have a lockshield cap. This valve is used to "balance" ie fix the water flow to that radiator. Leaving a "wheelhead" cap on the valve will allow the user to upset the flow setting to that radiator. See the faq's on balancing.
This lockshield valve is typical of 90% of valves I come across - it was probably provided free with the radiator from the ever so helpful merchant. He's not doing you any favours - they buy them in for less than a pound. It has no place in your home.
They are by and large rubbish, often leaking around the spindle (especially on sealed systems eg combi's). Look for valves complying with BS2767 Part10 - they have an extra seal around the spindle (always tighten this down at installation time). In particular look for valves with a graphite/PTFE seal avoid the O ring types. They are only a few quid but make a huge difference to the system. I spend half my life changing leaking valves.
Despite the owners handywork at this abortion the radiator didn't make the slightest difference to the room comfort, why? well it was the last one on the heating system pipe run and none of it was balanced properly - hence it did not receive sufficient water flow through it.
Use top branded thermostatic valves ie Honeywell, Drayton etc the cheaps imports are a waste of time.
Lastly make sure the radiator won't fall off the wall. I've seen a double 2 metre by 700mm held on with 20mm screws. Held up for 10 years then one day it got bored. The bedroom became a paddling pool.
And I only went to repair the boiler - new boiler heat exchanger required after 4 years - because of sludge in the system due to inadequate cleaning and inhibiting when the owner installed the system.
