On 23/10/2017 12:44, 100Packets wrote:

replying to Ed Sirett, 100Packets wrote:

Only 8 years late, and you are replying to professional heating systems
expert - so this is likely to be entertaining...

COmbi boilers do not have diverter values.

Strike one!

Erm, yes they do. Almost all of them.

The Domestic Hot Water is heated by a secondary water to water crossflow
heat exchanger. That in turn is heated by a flow of primary system water
that is heated by the main gas fired heat exchanger. That's the same
water that also flows through the rads. The way the boiler gets it to
flow through the DHW heat exchanger is via an internal diversion valve.

Hot water and radiator
systems are completely separate

Strike two!

No they are not. They both depend on the same primary circuit to provide
a pumped source of hot water, which can be use directly in the rads, and
indirectly for heating the DHW.


And you are out.



--
Cheers,

John.

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