Joeski wrote:I am really interested that he can do it with way less than 110,000 btu's too.
Heating using hot water is quite a bit different than heating with hot air. First, it saves money because moving heat by moving heated water is much, much easier to do than moving heat by heated air. Next is a science type thing of heating that makes it so the higher the temperature, the less efficient the heat. Hot air is the hotest so it's the least efficient, it starts out a few hundred degrees. Steam is next, just over 210 degrees, then hot water at 180, then radiant heat as it uses hot water that is less than 180 degrees. The lower the temp, the better you can control it, and the more money you save. People get confused between efficiency of cost and efficiency of heat. You can have a less efficient heat source that costs less money. Confused? I am too LOL Look at it this way: If you have a burner that's 100% efficient, but if you lose 99% trying to get the heat where you want it, that's not efficient. In every case, when the transfer medium is hotter, you lose more of it along the path of getting it from here to there.
SO.... radiant heat is more efficient because of it's lower temperature, but, also, it's got other systems beat in other ways: It heats the floor. If your feet are warm, you feel warm. It does not stratify the air. The temperature at the ceiling is much lower than other systems. A cool ceiling saves a BUNCH of money. Instead of 83 degrees trying to escape, it's more like 70 or 72. It tends to heat living things more than objects. People and animals feel the radiant heat. That means you can keep the house 68 and feel warmer than a hot air system at 73.(again, lower temps trying to escape) Finally, radiant is more efficient because it does not make the air move. Moving air costs money! Couple that with realizing that hot air ducts, radiators, baseboard, are always (and with good reason) put on the outside walls, radiant saves a big percentage because it is not moving air across cold windows, cold walls.
Carpet does slow up heat. You don't lose dollars as the heat IS in the house. Carpet makes for less efficient heat transfer through the floor, but it does not change the efficiency in dollars. The only thing is, thick padding & thick carpets might lower the transfer efficiency to the point that you do not move enough BTU's. If so you'll need either higher water temps in the tubing (now you might be dancing with losing dollars) or some baseboard to make up the difference on very cold days.
Finally, it's not that you can use a smaller boiler with radiant heat, it's that you need a larger one with other types of heat. With radiant, you are a slow steady heat. With other types of heat, the temp comparatively raises a lot when the device is running, and sits idle when not. Now the temp drops & you need a bigger device to get the temp back up.
Time for coffee!