flat panel radiators - mechanicals?

[mikeyvon]

I plan on using flat panel radiators for my new home. I was originally going to do underfloor radiant and I have a decent understanding of the zone mainfolds, flow pumps, controls, ect. for underfloor.

I am assuming that with panel radiators with thermostatic valves the mechanicals are pretty simple. Heat exchanger and pump for hot water heater, pressure tank, pump, and manifold with flow balancing. I have read about using a mixing valve, but I do not understand how it will fit in.

Can someone shed some light on the mechanicals side of a flat panel radiator system?

[jadnashua]

Infloor radiant rarely uses water the same temperature as a typical radiator, regarless of the form factor. Radiators are usually designed for 160-180 degree water temperatures. An in-floor system might only use 100. Most boilers won't work well only heating to 100, so they use a mixing valve to get the really hot water down to temperature (it mixes in the cooler return water with the hot, then that is fed to the system). I doubt you'd need a mixing valve using radiators. If you use a smart modulating boiler, you can program it to generate lower temperature water when the conditions call for it. This can allow the radiator to be actually getting heat all the time, just not really hot, then off, then hot again...constant, just right temperature hot water would be more comfortable.

[mikeyvon]

jadnashau - thanks for the comments.

We are not in a super cold climate with an outdoor design temp of 17 degrees. We also use a woodstove as primary heat. Due to those factors we will be using a water heater (AO Smith Vertex) with a heat exchanger to run the radiator side. All the radiator companies I have seen rate their radiators down to 120 degrees. We plan on running around 140-150 degrees and size the radiators appropriately.

As far as the mixing valve, I could have misheard (i did not understand as it was) but he was talking about using mixing injection at the heat exchanger to fully take use of the trv's instead of having them act just as on/off devices. I have no clue?

Again, I have a decent understanding of what it will take for underfloor radiant. I am trying to figure out what it will take, money and time wise, to set up the mechanical side of a hot water radiant system?

[jadnashua]

The surface area of radiant panels becomes significant when your supply water temps decrease, but any input higher than ambiant will supply some heat.