My sister wants a heating modification .... so it's come my way.
Currently there is a towel rail in bathroom, (aprox 0.45kW) which is not putting enough heat into the room, she has asked .. can she ( which means I) change it for a panel radiator (2.5kW) (opt 1)
OK physically I can get this done.
I have never used micro-bore pipes ... so want to do some sanity checking.
The Towel rail is fed by copper 8mm F&R pipes ... which is around 7.5m (F&R ) combined loop to combi boiler. The 8mm pipes run back to a Tee off the main 22mm F&R of boiler
If I replace the towel rail ... the new total run in 8mm pipe will be about 10.5m total loop length
I Know theoretical limit for 8mm pipe is 14m overall loop length, (typical pump head) ... but also read than 6m is preferred in practise
Does that mean that opt 1 .. removing towel rail and installing the panel rad, on it's own may actually be expecting too much out of the 8mm pipe. (or should it be OK?)
She then added Opt 2 ... could she add the panel radiator and keep the towel rail as well. Heat wise 8mm pipe has max capacity of 4.5kW so from that point of view keeping both is OK. (combined panel & Towel rail will be ~3kW)
However I know bends, friction etc., has impact, and simply adding the panel rad onto this 8mm F&R, may be asking too much from the 8mm pipe ? ... whadda ya think
If it is, then I could change out the connection at boiler to 15mm and only step down to 8mm at the rads. A pain, becomes much more work for me.