[GBlist] re: "Water" furnace?

[Ovid Curmdgeonsen Metamorphoses II <_meta_4@excite.ca>]

"Marilyn" <timex@dsl.ca>  wrote:

>'water furnace' and claimed to be more efficient and less costly to >run
than a 'conventional' furnace. 

>Does anyone know this product and if it is as good as claimed? 


MZ;

There was a time when Water Furnace (TM) was touted by NRCan as being the
most efficient ground-sourced heat pump (GSHP) on the planet. That may still
be the case for all I know.

There was also a time (about ten years ago ?) when a neighbour (who had a
Water Furnace installed in his home) complained to me that after only 3
years (?) of service, he was having to  replace the heat exchanger on his
furnace at a cost of in excess of $2k.

Apparently the failure was due to premature corrosion due to galvanic
reaction between a clamp and the copper tubing. Whether the inappropriate
clamp (ie dissimilar metals) was a stupid design error or a stupid error on
the part of a novice contractor installing the furnace, I do not know.

At about the same time, another person far away on the other side of town
was so fed up with his $10k+ GSHP (I don't recall the brand) after having
had to replace the heat exchange twice in less than 8 (?) years, that he had
ripped it out and was giving it away to anyone who would haul it away.

He said that in his case, the failures were due to the hard water in his
area. (I doubt if his water was any harder than the water in my
neighbourhood wells which is so hard that it listens to MegaDeth at
breakfast. BTW, two wells were required... one for supply and one for
discharge, drilled through good, hard, Canadian Shield rock)  I did not
inspect his heat exchanger so I can't vouch for the accuracy of his
assessment of the problem.

As an interesting side note: When I mentioned the above failures on this
List some years ago, a local engineer/GSHP dealer here in Kanata ON (who had
been sent a copy of my message by an architect in Calgary AB), sent me an
email telling me that he had never heard of any such failures. I provided
him with names and contact info. and as the song goes ...
chunka,chunka,chunka, that's all he wrote, momma.

That being said, I have no doubt that the operating costs would be far less
than a "conventional" furnace . 

However, one should note that the initial cost will likely be in excess of
$10k (compare to the initial cost of a toaster (aka electric furnace $300 to
$600), both of which require electricity to run ... or to that of a good
clean-burning woodstove (initial cost 
starting at about $800 including chimney) ... and if the heat exchanger
problems have not been eliminated in recent years, one might expect ongoing
costs of $2k+ every three years or so... so less costly ? It depends.  

Me ? I think that the up-front $$$ might better be invested in envelope
improvements so that one is better able to hang onto solar and occupancy
gains, and perhaps a few bottles of wine now and then to entice warm bodies
to visit when the temperatures drop.


Elvis

Please visit: www.the HungerSite.com  daily





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