No drain valve on hot water system

[realpants]

I am wanting to replace an old corroding radiator and to do this I have to drain the system, however there isn't a drain valve.

I understand I have to shut the water off, and somehow drain the system, but how do I do it.

I will want to fit a drain valve to an exhisting radiator for next time. Which way does the water flow in the radiator? which will help me when re fitting a drain valve, using a lockshield incorperated.

Is it possible to use compression joints on the pipe work leading up to the rad?

Is it possible to use plastic pipe for ease of resiting the new rad?

 

[seco services]

shut both the valves on the rad your changing and slacken one of the joints between rad and valve and just drain the rad first.
then remove the rad then you can drain system from one of the rad valves.

 

[realpants]

Does it matter which rad valve you connect the hose too?

 

[seco services]

no they all join in the end.
is it a vented system or sealed ?

 

[realpants]

vented system.

 

[seco services]

just tie up the ballcock if you haven't an isolation valve and off you go.

 

[realpants]

Do I need to do anything with the pump next to the large copper tank?

Is it really that easy?????

 

[seco services]

no just make sure the programmer is off and not left on timed to come on for hw/heating.

 

[Master of None]

Be sure to vent the pump after you refill. Its usually a screw on the head of the pump.

 

[realpants]

How do I know which way to turn the pump screw? Daft question maybe? At what point do I turn it back?

 

[seco services]

unscrew is anti clockwise
tighten is clockwise.