Oops...
I replaced the bathroom radiator at the weekend - drained the system, replaced the rad, refilled and everything was hunky dory: CH working perfectly.
However, there is no hot water now. What am I likely to have done?

The system is an old fashioned boiler, not a combi, and that is working as it should, but there is no water from the taps, unless I put the immersion heater on (obviously).

Any ideas?

Cheers scruff.
There is water coming from the taps, but it's cold, and the tank itself is cold too.

I found the air vent next to the cylinder and released loads of air from it while refilling the CH system.
There has since been loads more air released (it's not my house, it's my my in-laws')

So is it just a question of letting everything circulate, and releasing air until it works? Or is there a way to force the air out (like you guys helped me do with my radiator last year).

As always, I greatly appreciate your advice.

If the rads get hot but the H/W tank doesn't then... Perhaps when the system was drained you got some crud in the valve? It could be stuck pointing in the heating direction?