Here is a modified version of the previous chart, the 1LC heater has been added.
To troubleshoot a heater you need to know what the readings should be.
Below are the expected values for each heater. (1LC - T500)
Here is a video that will walk you through the whole troubleshooting process:
http://www.youtube.com/watch?feature=player_embedded&v=gzaSeebb_JwTo test the element, set your meter to Resistance, and place your leads on H1 and H2 on the board. (See chart for expected resistance.)
Heater -----------------------Watts (W)--Volts (V)-Amps--(A) Resistance (Ω)
(1LC) 1" 120 VAC 1Ph.-------100---------120------0.83---------144.00
(1LC) 1" 240 VAC 1 Ph.------100---------240------0.42--------576.00
MiniMc® 1" 120 VAC 1Ph.----300---------120------2.50---------48.00
MiniMc® 1" 240 VAC 1 Ph.---300---------240------1.25--------192.00
2" 120 VAC 1Ph.--------------800---------120------6.67---------18.00
2" 240 VAC 1 Ph.-------------800---------240------3.33---------72.00
4" 120 VAC 1Ph. ------------1200---------120----10.00---------12.00
4" 240 VAC 1 Ph.------------1200---------240-----5.00----------48.00
No. 28 120 VAC 1Ph.--------1750---------120----14.58----------8.23
No. 28 240 VAC 1 Ph.-------1750---------240-----7.29----------32.91
No. 28CU 240 VAC 1 Ph.----2270---------240----9.46-----------25.37
No. 250 240 VAC 1 Ph-------3000---------240---12.50----------19.20
No. 250CU 240 VAC 1 Ph----2270--------240----9.46-----------25.37
No.412 240 VAC 1 Ph--------3000--------240----12.50----------19.20
No. 618 All 240 VAC 1 Ph.---3000--------240----12.50----------19.20
T500 All 240 VAC 1 Ph.------4000--------240----16.67----------14.40
T500 Series III --------------5000---------230----21.74----------10.58
The RTD (Restistance Temperature Detector) should have a resistance of 108 ohms at room temperature.
The potentiometer should have a resistance of 9.5k-10.5k or 5k at max. Make sure that you set your meter on 20
k.Make sure that you have one lead on the white wire and one on the red or black. Test the unit across the whole range of temperature settings. It should never read open.
Jumpers:
One on pins 2 and 3 if it is for a 240V unit.
One on pins 1 and 2 and one on pins 3 and 4 for a 120V unit.[/quote]