Baseboard heater Help! - DIY Chatroom

jweinstock · 10-28-2006, 01:51 PM

Hi,

I am a DIY'er and am trying to install a baseboard heater (120V) in my bathroom remodel.

The old heater was 240V but I was told that I could simply cap one of the two hot lines and use the same line to connect the new heater.

The old 240V line looks like its 10/3 and the new heater takes very few amps and has twisted 14/2 (? - I think, its a much smaller gauge).

When I test the old line (1 hot wire capped) with a wire tester I can see its got juice, but when I connect the heater I get nothing. Not only does the heater not turn on, but when I try to test the leads on the old line, I don't see any juice there either. If I disconnect the heater and re-test juice is there!

I know the heater works because I tested it against an outlet with the cord stripped on one end and connected to the heater.

Is there something wrong with capping 1 line of a 10/3? Can you not connect wires of a large gauge to a smaller gauge or something like that?

Help!

Thanks
JW

Speedy Petey · 10-28-2006, 02:24 PM

Is it definitely 10/3? Black, white, red, ground?

Are you capping off the red or black? And using the white as a neutral and ground?

Is the white connected in the panel? It was NOT needed for the 240v heater so it may not be hooked up.

How did you test it? Do you have an actual voltage tester that shows the voltage?

jweinstock · 10-28-2006, 02:34 PM

Hi,

The Old 240 Volt Line is BX cable so its Black, White, Red in the flexible metal conduit.

I tried capping off both the red and the black (not at the same time ofcourse), but switching that did not seem to make a difference.

I will check whether or not the white is connected at the panel but my sense is that is since this line (the 240 V) is also used to power an A/C unit. Whoever wired the circuit must have figured that only 1 of the A/C or heater would be used at the same time.

I tested using a voltage tester that lights up. I tried to buy a tester that shows the actual voltage but am having trouble deciphering it. Best I can tell, when I connect that tester it looks like the voltage is less than 120 (may 105? if that makes any sense). Ofcourse, I could be using it wrong.

I'll double check the neutral is connected at the panel.

sootybuttercup · 10-28-2006, 02:58 PM

If the problem is "no neutral (white) connection at the panel", make sure before you connect it that the neutral isn't hanging loose at the AC unit. Also, what kind of 120v baseboard are you installing? Lastly...does the cable go from the panel to the heater, then to the AC...or AC first, then heater...or are there 2 cables connected to the same circuit at the panel??

jweinstock · 10-28-2006, 03:02 PM

I verified the white is connected at the panel.

The 120v baseboard heater is a 2ft QMark heater. I believe the amp is approx 4.

The cable from the panel goes to a junction box where it is forked into 2 lines, one going to the A/C and other going to the bathroom. So both the A/C and the heater draw off the same 30 Amp Breaker.

The A/C works without any problems, which doesn't do much in November for us

sootybuttercup · 10-28-2006, 03:16 PM

Assuming that the whites (neutrals) are solidly connected at the junction box...you should read around 120 volts (AC) on your meter when measuring from the white at the heater...and either of the other 2 wires (red or black). You should read 240 volts from red to black. Is this 240 circuit fed from a double pole breaker (double width or 2 handles connectd together) or is it a fuse panel? When using your meter, make sure it is set to AC (some times identified with a ~ symbol). Oh...be careful, too!

redline · 10-28-2006, 06:01 PM

A 240 volt heater should have been cheaper to buy and draw less amps then then 120 volt heater.

and a direct connection.

Do you need to install a thermostat?