Andy Jeffries wrote:
On Tue, 19 Aug 2003 00:53:01 -0700, Vince wrote:

We've had a combi-boiler fitted, early this year, to drive the heating
and hot water. It seems to be working fine at the moment. The thing
is though that the hot water comes out white and it takes a few
seconds in the sink before it clears.

Thinking about it (though it's probably unconnected) - the central
heating does not have a header tank but is fed from the mains via a
valve. I check the central heating pressure periodically and let more
water in if the pressure drops. The thing is, the pressure does drop
so I'm having to allow a bit more water in every month. Doesn't sound
right to me but I still can't find any leaks anywhere.


Just wanted to let you know that I'm having exactly the same two symptoms.
Hadn't worried about it until now! :-)

Didn't know if you wanted to know that you weren't alone!

Cheers,


ANdy

Make that three of us :-)

I don't worry about the white these days - it's a lot less noticeable
now the boiler is working properly at last and I can get a high
throughput instead of a pathetic dribble out of it. Lower flow rates
with a high temp just starting to form seems to be the time that the
white shows up. I've wondered if it is scale that forms inside from the
last cycle being broken free in minute particles when the boiler heats
for the current HW demand, but putting it into a glass the water soon
becomes clear so I don't think it can be that.

Both combi's I've had have had slow leak symptoms, but I rent, so I'm
not going to pull up all the floorboards to check the rad pipes. I just
top it up every so often (the new boiler is a lot less prone to this) -
and also, given the filling loop is permanently connected, I wonder if
it is going back through there despite a check valve.

I don't worry about either - I don't drink the hot water, so that's not
an issue, and the pressure drop in the heating circuit is so small as to
be negligible. One thing to consider is if you run the heating very hot
the pressure may build up and the boiler vent slightly on it's pressure
relief valve, mine's custom settable by the boiler engineers - or maybe
a slow leak through the valve. Looking at the vent pipe may indicate if
this is the case.

Velvet