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Old 03-31-2009, 06:05 AM   #6 (permalink)
aero guerrilla
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Join Date: Oct 2008
Location: Warsaw, Poland
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Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
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Originally Posted by AC_Hacker View Post
> ...a radiant floor system should have at least 8 meters of pipes
> per square meter of floor.

Interesting... Most of the hydronic systems in the US consider 6 inch spacing to be the minimum. Your specification works out to about 5 inch spacing.

If everything else is equal, your spec of 5 inch spacing should prove to be more efficient.
The closer the spacing, the more pipes you get in, and the lower the temperature, which does raise efficiency. Also, with more water in the system you might not need a buffer tank.

As for our heat pump: Our lot is small with lots of shade year round, so we'd have to drill. On top of drilling costs, local laws require permits and fees for drilling, while the soil under us is dry (wet is better for GSHP). The guy I talked to said that maybe it'd be worth it if we were building a new house, but not when retrofitting an old one. For a fraction of the cost we could add insulation and exchange our oversized natural gas furnace for a smaller high efficiency (107%) model, and then the bills would not be much higher than with a heat pump and radiant floors.
We will get a heat pump, but an air-water model for heating water with waste heat from the ventilation. That, plus a new ventilation system and solar panels for hot water, will be in a new thread when we finally get that project going.
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell

[Old] Piwoslaw's Peugeot 307sw modding thread
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