The Motley Fool Discussion Boards

Previous Page

Personal Finances / Building / Maintaining a Home

URL:  http://boards.fool.com/goofyhoofy-perhaps-it-would-have-worked-with-the-20118815.aspx

Subject:  Re: Radiant Heat System Date:  1/8/2004  4:59 PM
Author:  Radish Number:  44389 of 129260

Goofyhoofy,

Perhaps it would have worked with the "Ultra-Fins", but the PEX pipe they use doesn't bleed heat as well as copper, so perhaps it's a wash. (Perhaps not, I have no way of knowing.)

Indeed. Probably finned tubing like http://www.energytransferinc.com/finned.htm or more exotic heat-exchanger tubing like http://www.heatroninc.thomasregister.com/olc/29887007/thermek.htm would have helped, as well as lightened your wallet considerably.

In my case I can run a return pipe for the hot water circulation. My thought is that once I find out how long (and what diameter) the hot water piping is, I can look up the expected rate of heat loss. Then I can pick a minimum desired temperature for the static hot water, and from that figure out how many gallons per day of hot water would need to be circulated, at most, to maintain the desired temperature. I expect this will be a small number, and that a very small pump could simply run continuously (rather than being thermostatically controlled, like the Auto-Circ models).

So my thinking for the floor is that I could run supply and return lines from the water heater to the bathroom floor (it's not far) and run tubing back and forth under the floor, much like you did. Then connect the output of the circulation pump to the supply line, and connect the return line to where the circulation pump would normally connect. And, place a solenoid valve from the supply to the return line where they connect to the pump. With the valve closed, water would have to flow through the floor system. With it open, the floor system would be effectively "short-circuited" and have little, if any, flow. Then control the valve with a thermostat in the heated floor, much like the NuHeat people do.

Any thoughts on the feasible of that?

I have looked at NuHeat. It seems to have two disadvantages. One, it is easily damaged during tile installation. I've had enough problems with tile installation to be leery of creating opportunities for more. Two, it's electric. Where I live, electricity is priced considerably higher than natural gas.

Phil
Copyright 1996-2014 trademark and the "Fool" logo is a trademark of The Motley Fool, Inc. Contact Us