SPCR

Actually, considering where the pipes are mounted they may actually get cooler when a fire is going.

As the fire burns it moves a considerable volume of air up the chimney, so cooler air form the room is pulled towards the FP. And since most of the heat from a firplace is given off as radiant heat, and the tubes are out of the line of sight of the fire, the cooler air passing over them may lower the unit's °C/W.

(This is only true if the FP is an open unit, and not a direct vent.)

Considering the weather Wisconsin's been having lately I'll be willing to bet that Joe will be able to answer this question pretty soon.

We haven't been low enough yet, my room is still toasty warm without the heat on thanks to all the folding power

But on topic, it would be interesting to see if the fire helped or hurt.

that looks like wood to me :O

Yup, it's a wooden template for routing the water passage and o-ring groove in the acrylic blocks. A guide ring on the baseplate of the router runs along the inside of the template. In the picture, the top piece of acrylic is attached under the template on the left.

Actually, considering where the pipes are mounted they may actually get cooler when a fire is going.

That's what I think, too. I haven't had a fire yet this year, but when one is going there is a lot of air moving through the fireplace. If the temps get too high with a fire going, I'll turn the computer off. Maybe read a book