[GBlist] hot water rads

["L84Work" <m.tymoshuk@rogers.com>]

I'm looking for some help selecting a hot water rad system to heat my home
new. When considering economics of the system, which is the least expensive
to operate and install.

For example:

1) Solid steel or cast rads (stelrad, runtal) are considerably more
expensive than copper fin rads (slantfin).  I've heard that copper fin tube
rads act more like a forced air heating system since they convect more than
radiate.

2) If you run hotter water then you can have less rads, but with solid steel
rads they also become very hot and dangerous with small children around. Is
it more or less efficient to heat hotter water?

3) A boiler with a storage tank is very expensive to buy but provides hotter
water so you don't have to buy so many rads.

4) A combination boiler may be more economical since no storage tank is
required and no stand by losses are reduced. However they are still
expensive.

5) A polaris hot water heater may be an option but what is the maximum water
temperature that it can pump out and have heard that when it breaks down it
is expensive to fix. Also can the water temperature be automatically
adjusted according to the weather like boilers to reduce the water
temperature when the weather gets mild?

6) I've been told that instantaneous hot water heaters like Rannai are not
meant to heat a home and the domestic water as well. The warranty is reduced
to 2 years if this is the case. Problems develop with pressure and
anti-scalding plumbing valves and installation is tricky.

I'm thinking that a polaris unit and fin tube rads may be the best trade-off
if the water can be hot enough to reduce the number of rads.

Any help greatly appreciated.

Matt Tymoshuk
Brampton, Ontario



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