"Doctor Drivel" wrote in message
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"Steve" wrote in message
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"Doctor Drivel" wrote in message
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Have the cold line to the
showers off the 22mm line to the combi, just before the combi. Then if a
pressure drop around the combi there will be equal pressure to the showers
hot & cold.

Interesting idea. However there will be some extra resistance to flow for
the water passing through the combi's heat exchanger.. Also, in my case,
there will be a much longer path for the water going through the combi
compared to the shower's cold supply.. If the combi and shower cold
supplies are both 22m, then the cold would end up at a higher pressure than
the hot. The answer is a thermostatic shower!