Having trouble bleeding radiators

[cha]

My radiators need bled, I cant find the radiator valve, everyone tells me its should be at the top left side , but there is nothing on either side of my radiators. When i tell people this, thye say I am wrong.. but really there is not radiator valve anywhere that I can see, top, bottom , behind.
The central heating was installed about 10 years ago, the boiler is a vokera combi, I dont know what type of radiators i have.
I have bled other radiators before so Im baffled, how do I clear the air from these cos they are cold at the top

 

[breezer]

may be on the back (top right) , i have one that has a bleed valve there

 

[kevplumb]

you have barlo rads do as breezer says might feel a lump its a plastic cap take it ott the bleed screw is underneath

 

[graham365]

Just out of interest, what would happen if you *didn't* have a bleed screw on one side/at the back? i.e., for example, if there was a second stop valve where the bleed valve should be? Would it do any damage, or would it just be an inconvenience (because you'd have to unscrew the stop valve every time you wanted to bleed the radiator)?

 

[kevplumb]

whats a stop valve

 

[graham365]

whats a stop valve

Sorry, not expressing myself correctly.

I meant to say, what would happen if you closed off *both* top parts of a radiator, i.e. you didn't have a bleed screw (just a sealed end where the bleed screw should be), so you'd have no practical way of bleeding the radiators.

Basically, I guess I'm asking what would happen if you never bled a radiator -- would it just become less efficient, and colder, or could you circumvent any problems by bleeding other radiators in the same system?

 

[kevplumb]

if you think about it
if rads are bboe you will never shift the air till it gets to the valves which means the rad is empty
Bottom Bottom Opposite End
hope this clears it up for you

 

[graham365]

So does that mean the radiator will just gradually fill up with air if it never gets bled? (Sorry if it's a daft question, I don't know much about it)

 

[croydoncorgi]

In fact, in a typical house, air will tend to collect upstairs rather than downstairs and in cooler radiators rather than hotter ones. As pressure and temperature increase, water can absorb more of a gas. Think of the bubbles that form in a bottle of Coke when the pressure is taken off.