On 30 Mar, 06:39, David Hansen
wrote:
On 29 Mar 2007 13:19:38 -0700 someone who may be "jives11"
wrote this:-

Many thanks. I had not thought of that. So how do solar water heating
systems avoid this ? I'd assumed they preheat stored water before it
enters the boiler.

Assuming you are thinking of the domestic hot water heating part of
a combination boiler, the solar panel will feed a relatively small
hot water cylinder from which water to the boiler is drawn (either
directly or via a heat exchanger). The combination boiler must be
able to accept heated water.

--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Thanks. I wasn't thinking of a combi. My system is a fully pumped
system with ho****er tank.

I had assumed that anything that raised the temperature of the water
in the HW header tank would reduce the amount of gas and hence CO2
consumed.

So how do solar hot waters heat the water ? Is there a secondary coil
in the hot water tank, through which the solar heated water is pumped
OR do they raise the temperature of the water in the storage tank.
Sounds like the latter is unlikely given the health issues with having
quantities of warm water hanging around with only a lid protecting it.