Turning room thermostat down, doesnt cool room

it is not car, at all so moved to heating home.
seems you are in UK with bar pressure? (ISO rules) and
straight away<< jargon
I say golly good show mate.

how cold outside, London?
is this the only heater in the home
or just heat in one heatless room
what is meter square of room or total area of space to heat.
what is BTW rating of heater.

I say buy a heater with a REAL thermostat and end this pain.
dial up 20c and be happy,
but the BTU of the heater must exceed , the loss of heat, in home or room insulation,
but I say , its a thermostat missing problem..

2 speeds, one toO much ,1 too little
or have youR HVAC PERSON ,(TECH) ADD IN A THERMOSTAT.
REAL.

Hi,

please check the vents in the rooms that are not cooling well. There might be a hole/leak in your heating system. The thermostat itself might not be the problem. If possible, please research google nest to check if it has multiple thermostats that can be used to more accurately state the average temperature across several rooms of your home.

You might need to get an hvac diagnostic to find and plug all of the leaks in your home before deciding to alter any of your heating system.

Thank you.

How Your Car's Heater Works (Or Doesn't) ' AC Pro

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At A/C Pro, we're focused on helping people stay cool with our do-it-yourself car A/C repair kits. ... dropping, drivers are switching off the A/C and turning on the heater. ... When you turn on your car's heater, the hot coolant flows from the engine to ... Or it could be that the thermostat, which is a valve that regulates the flow of ...

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With a two story house you have to be aware that cold air flows downwards so any cold air coming from an ac unit will flow downstairs( normally down the stairway) so unless you can close off the down stairs then the up stairs unit will be cooling downstairs as well. Ac units have a thermostat located in the air intake and it cools until the cold air has risen to that point. In effect the space above the ac unit will be hotter than the floor. Knowing how they work ,you can see that the upstairs unit will never reach the set temperature because the cold air is continually heating from the house and will never get to the top thermostat.
So your solutions are
1-- fit controls that restrict the cold air from leaving the upper floor (Doors)
2--don't run the upper ac unit unless you are living up there (waste of money
)3 place an ac in each upper room and keep the room door closed

It will be the thermostat that turns the compressor off.

Bad thermostat or temp sensor.

It may need cleaning, if it cools when you turn the thermostat down it does not need refrigerant, the unit may have a thermostat our of caliabration.

Try the Worcester tech help line they are good

Verify 24 volts at the low voltage transformer inside the air handler. If it is OK, jump out the red/green and yellow thermostat wires. If everything comes on, replace the thermostat.

This is normal operation for these styles of minisplits. The thermostat is not in the remote but is located on the return air of the indoor coil, so the air needs to be flowing in order for the thermostat to measure the rooms temperature. Set your fan speed to auto and the fan will slow down when setpoint tempurature is met.

Phil Hodges,
Tech support Soleusair