On 29 Dec 2005 13:29:39 -0800, "htmark98"
wrote:

Thanks for the link andy.

will probally do the 1st choice as i'll do all 3 and work back to the
22mm then.

Now as the run of the 15mm goes straight across the 22mm and feeds 6
rads, would it be better to cut the one feeding 4 rads on it's on run
to be sure.

You can apply exactly the same rule for 22mm pipe as for 15mm - I
forget what its maximum carrying capacity is - but you can work it out
from the CDA paper. As a clue, it's only in pretty large
installations that it is necessary to exceed 22mm for the first run
from the boiler, so you can work it the other way based on boiler
output.



Is there a rule how many times i can cut into 22mm pipe? the pipe is
only about 2m long.

No it's OK. Bear in mind that you need to keep a metre or so from the
boiler if you use plastic.

Once you have finished, it's quite likely that you will need to
rebalance the system as a whole to achieve correct water flows and
temperature drops across all the radiators.

There are two ways to do this in the group FAQ.




--

..andy