I also found the pressure was very low.
Cold radiators on top floor.
In some houses it may be a slight inconvenience.
Other radiators on the top floor are working fine.
No more it s too hot upstairs one of the most common complaints many of us have about our homes is that it s too hot upstairs or too cold downstairs.
It takes one pound of pressure in the boiler mounted gauge to every 2 36 feet of height to the system.
The radiator is warm at the top but cold at the bottom these symptoms usually mean that there is a build up of sludge settled in the bottom of the radiator.
Before you spend any more time fiddling with the thermostat.
This is a bigger job which you may not wish to do yourself as it requires removing the radiator from the wall and rinsing it through which can be a messy and time consuming job.
Am guessing there may be an air lock somewhere between the second and third floor but any advice would be much appreciated.
As the system refilled i walked around floor by floor opening the bleed valves so air could escape.
Cold radiators on top floor.
I have tried the heating on with every other radiator turned off the top floor stayed cold.
I ve now topped this up and bled all radiators but the problem remains.
I replaced both zone valves on my ch system due to a fault with the hot water becoming blindingly hot and not being able to shut the system down via the programmer.
Make it somewhere between 13 15 and you ll be in good shape.
When the heating was put on i found only the top floor 4 had hot radiators looking at previous posts here i loosened the bleed screw on pump no indication of any air and tuned all bar 1 radiator off on floor 4 one radiator got hot on floor 3 turned off the one rad on top floor 4.
I ve noticed now having put the heating on that 3 rads on the top floor are stone cold as are the pipes to and from the rads.
This cured the problem but on re starting the system the pump started to make a noise like a howling banshee so i replaced this also.
In others especially in older homes this problem may be a symptom of a more serious issue with air flow insulation or efficiency.
So if the boiler is in the cellar and the highest radiator is 30 feet above it on the top floor the pressure gauge must read at least 12 71 psi when cold.