Hydronic panel heating or cooling system

A method for heating a room comprising:

• pumping water through a heater wherein the water is heated;
• pumping the heated water through an extruded panel having contiguous channels disposed in a room to be heated;
• wherein the heated water is pumped through the extruded panel so that it first passes through a first chamber at a first end of the extruded panel, then passes through a first subset of the channels, then passes through a second chamber disposed at a second end of the extruded panel opposite from the first end, then passes through a second subset of the channels, and then passes through a third chamber at the first end of the extruded panel;
• wherein at least some of the channels are blocked by plugs at both ends to thereby direct the flow of water through the panel;
• wherein the room receives radiant energy from the heated water through a surface of the extruded panel facing toward the room.

A method for making a hydronic panel heating system:

• providing an extruded panel, having contiguous, fluid-tight, parallel channels running from a first end of the extruded panel to a second, opposite end of the extruded panel;
• adding a first chamber to the first end of the extruded panel, which is in fluid communication with a water inlet and first subset of channels;
• adding a second chamber to the second end of the extruded panel, which is in fluid communication with the first subset of channels and with a second subset of channels;
• adding a third chamber at either the first end or the second end of the extruded panel, which is in fluid communication with at least some of the channels and a water outlet;
• providing blocks at both ends of at least some of the channels to thereby direct the flow of water through the panel;
• providing a heater for heating water;
• and
• providing a pump for pumping heated water through water inlet, the chambers, the channels and the water outlet.