Note at this stage the air pressure ceased building up on the top third floor radiators so i turned the heating on turned up the thermostat and went back around the system releasing air.
Cold radiators on top floor.
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.
Cold radiators on top floor.
I ve now topped this up and bled all radiators but the problem remains.
Make it somewhere between 13 15 and you ll be in good shape.
It takes one pound of pressure in the boiler mounted gauge to every 2 36 feet of height to the system.
Am guessing there may be an air lock somewhere between the second and third floor but any advice would be much appreciated.
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.
In some houses it may be a slight inconvenience.
If some of your steam heat radiators are not getting hot the steam vent may not be working may not be venting at all radiator stays cold or may be venting too slowly radiator heats to proper temperature but too slowly if a steam radiator valve is open but the radiator is still cold the steam vent may not be working.
I have tried bleeding the top floor radiators they all have water in.
Other radiators on the top floor are working fine.
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.
I also found the pressure was very low.
Before you spend any more time fiddling with the thermostat.
In others especially in older homes this problem may be a symptom of a more serious issue with air flow insulation or efficiency.
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.
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 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.
I have tried the heating on with every other radiator turned off the top floor stayed cold.