On 1 Sep 2003 13:04:45 -0700, (C-H Gustafsson)
wrote:

Hello all,

I'm not in the UK, but as this is such a nice newsgroup with a lot of
knowledgeable people I thought I might ask this here.

My parents bought a house a few months ago. What worries us is the
underfloor heating. There is a pool which is heated by the central
heating system via a heat exchanger. Unfortunately, it turns out that
the heat exchanger is shot. This meant that the pool water and the
central heating exchange water. Not just a little: You could just as
well have skipped the heat exchanger according to the plumber. Both
the pool and the central heating systems are a D-I-Y setup and the
professionals had difficulties understanding it. Therefore, we don't
know if the water has gotten into the underfloor heating, but it's
possible.

Is this something you should be worried about? Could the pool water
have damaged the UF heating? Of course, the system is now shut down.

The pool water won't generally have concentrations of chemicals enough
to damage the heating system directly (humans swim in it). However,
the risk would be from oxygen being continuously introduced into the
heating circuit. This would typically cause problems with iron and
steel components - e.g. boilers and conventional radiators. UFH
pipes, from what I've seen are either plastic or copper wrapped in
something to protect it from the concrete. You could confirm that.
I would expect that flushing it through with fresh water and refilling
would be adequate. There might be some accumulation of rubbish from
the pool if the filtration wasn't working.

I you want to replace the heat exchanger, you have an excellent local
manufacturer.

http://www.gea-ecobraze.se




If it's a problem, how difficult is it to replace the UF heating? Is
it better to leave it alone and go for ordinary radiators?

If the floors are concrete, pretty difficult, but I don't necessarily
think you have reached that point.



Next question: The central heating doesn't work. It turns out that the
heat pump (air to water) is a lot older than the house, apparently
bought second hand. My parent's were quoted the equivalent of £3000
for a new heat pump, plus installation costs and necessary repairs to
the system. Is that reasonable? I don't remember the input power, but
the output is supposed to be about 10kW. I've become all confused
after reading data sheets from different manufacturers: Is there a
standard air temperature where the output power is measured? If not,
how are you supposed to compare different manufacturers?

I suppose the writing was on the wall. The previous house burnt down,
this house (built on the same basement) has been flooded and the two
previous owners went broke on the house without finishing it. The
sewer is damaged, there is no ventilation, electrical is not what it
should be and so on. But, hey, it's for all those suprises you own a
house, isn't it? ;-)


True, but you do get to have artsoppa on Thursdays, koettbullar with
lingonberries and Westerbotten ost, which IMHO, more than
compensates. :-)




..andy

To email, substitute .nospam with .gl

Andy Hall wrote in message . ..

The pool water won't generally have concentrations of chemicals enough
to damage the heating system directly (humans swim in it). However,
the risk would be from oxygen being continuously introduced into the
heating circuit.

Luckily, the underfloor heating doesn't work unless you close the
valves to the pool. (The water would just have pool temperature.) It
also appears the valves for the heating have been closed when the pool
was heated. Therefore, oxygen and pool chemicals should only have been
introduced when they switched between pool and underfloor heating.
(Spring/autumn)

I would expect that flushing it through with fresh water and refilling
would be adequate.

That's wonderful news!

----------
Bob Minchin wrote:

Heat pumps for heating are pretty rare in the UK apart from ultra high
efficiency 'green' specialist installations.

The standard heating in Sweden is electrical radiators, but this house
was built by someone with a special interest in heating solutions. UFH
was almost unheard of in Sweden when this house was built a few years
ago. In addition to the heat pump, there is a back up system with
electric heating. There are also connections for solar collectors, but
no solar collectors. Additionally, it looks like the house is prepared
for air conditioning and/or air heating.

If pool water has got into the UFH then I can't imagine it has done much
harm.

Again, that's great news.

So it looks like you will be spending a fair bit but I guess with the
knowledge of the history of the property, you would have got it
cheaply
and would be expecting some bills.

Yes, bills were expected and the price was a bit lower than it would
have been if the house was finished and didn't have any problems. But
the heating system was among the things that were supposed to be
working.

/Clas-Henrik