Calling all plumbers.........Can someone help me with the following questions, I am about to install a sealed central heating system but I need to know the following before I begin....Please help me!

1. The pipe work for the rads leaves the boiler in 22mm and then reduces to 15mm pipe. Is there a set distance where the reducer has to go or can it go anywhere.

2. Do you do one floor of rads and then go upstairs, or can you come out of the boiler then T off and do both floors at the same time.

3. If you do a floor at a time do you do upstairs or down stairs first.

4. 1 side of each rad has a TRV, does it go on the flow or the return.

Thanks!

TWENTY SEVEN readers and no one has helped me, 1st time on this site, what am I doing wrong????????