install radiant heat [Archive]

Anonymous

September 12th, 2002, 06:02 AM

Posted by: Wgodorich
Posted - 04/03/2002 : 15:18:25

If you ceiling is 8' tall and if you are in the longitudinal attitude of midwest North America concerning north and south then you should need 6.8 Kw of heat. If you are installing baseboard radiant heat then check your manufacturer to confirm that the watt rating of your baseboard heaters are 250 watts per foot of heater. If this is true then you would need approximately 27 feet of baseboard heat. A 20 amp 240 volt branch circuit is capable of carrying at an 80% loading a total wattage of 3.8 Kw or 3,400 watts. You would then need to split your heaters heating that basement into two 240 volt 20 amp branch circuits using two wall or baseboard mounted thermostats setting up a zone heating system having two zones of heat in your basement.

The baseboard heaters should be placed so that they will block convection heat loss of windows and drafts of doors to the outside. The heaters should be placed on outside walls to compensate for convection cold from the basement walls. Your comfort zone to your body would improve if you built 2 x 4 walls in front of the cement basement walls then install insulation to seal the room from heat loss.

You should also be aware that baseboard heaters are not allowed by manufacturer's recommendation to have receptacles to be placed over the heaters except over the ends of the heaters where the junctions are made to avoid damage to any lamp cords melting due to the heating elements.

You also must keep in mind that large pieces of furniture can not block those heaters for safety sake and curtains are not allowed to drape in front of those heaters.

Designing the branch circuit you should install a 20 amp 240 volt breaker in the panel for each heating circuit then install a 12/2wGrnd from that breaker connecting both the black and the white wires to the 240 volt breaker lugs and the bare to the grounding bar of the panel. Then you need to install that 12/2wGrnd cable to the thermostat connecting the power to the thermostat then fed from the thermostat to the heater or heaters. The heaters should have a romex connector securing the 12/2wGrnd to the heater entering behind the heater at the end of that heater. If you have more than one heater installed off one 20 amp branch circuit then you may install a second 12/2wGrnd Romex cable into that romex connector and connecting all the blacks including one of hte black wires of hte heater to together. Then wire nut all the white wires together with the second black wire of the heater. Repeat this wiring style in the second or third heater being ran from that one 20 amp circuit.

Then repeat from the panel through the second thermostat to the remaining heaters designed to be controlled by that second thermostat in the same manner that you wired the first branch circuit thermostat and heaters.

Hope this helps

Wg