On Wed, 09 Dec 2009 12:29:09 -0800, NT wrote:

no big deal. Historic CH systems often had *all* the rads in series

I don't know how historic you're getting here. I've not come across any
such. Even single-pipe systems don't put the radiators in series: each
rad has a bypass pipe in parallel with it, and the rad+bypass
combinations are in series with each other. This is quite different to
what the OP is asking about, if you think about it.





--
John Stumbles -- http://yaph.co.uk