NO HW or CH, gravity System

I have moved into a house, where it is a very old CH system, and does not work. There are imerial size pipes. It is a gavity system, with one pump for the radiators. I installed new radiators in all the rooms (8). I have no hot water and CH radiators. I can hear the pump working, and the boiler (Ideal Mexico, floor mounted) can hear working too. I cannot find a motorised valve. It took 5 days for the updastair radiators to fill up after I had drained the system. I cannot put that sludge removal chemical into the expansion tank unless I have hot water in the system. 1) How do I activate the Hot water to work again, 2) Enable the radiators to work.

Thanks Kindly

Is the boiler firing? Do the pipes to the hot water cylinder get hot? Does the boiler start and shut down quickly, or stay on for a long time?

Taking the radiators 5 days to fill up after draining the systems (Should normally take less than 1 hour) could mean that you have a
partial blocked pipe from your loft tank ?
Did you bleed the radiators as you were re- filling the system. This has to be done and means dashing from rad to rad to do it properly and frequently going back to rads again and again. Whilst bleeding the rads the pump should be switched OFF.