Check Heater 1 Circuit

12 VDC Circuit 1. Determine Which Test This Alarm Occurred In a. Review active alarm list. Make a note of all alarms. b. Clear active alarm list. c. Restart and monitor Pretrip. Stop Pretrip during Test #3 by holding = Key for 6 seconds. d. Review active alarm list for Alarm 187. If alarm is present, follow steps 2 through 5 If alarm is not present, follow steps 6 through 9. 2. Check 1HTCON1 a. Inspect heater contactor coil and wire connections. No damage to coil. Wire connections to contactor coil are tight. No damaged or corroded wires to contactor coil. b. Check contactor coil resistance. Refer to Section 2.11 for correct electrical values. 3. Check 1HTCON1 Amp Draw - Check 1HTCON1 amp draw. Use Component Test mode (Section 5.2.4) to test. Refer to Section 2.11 for correct electrical values. View current draw in Component Test mode screen. 4. Check 1HTCON1 Wiring - Inspect harness and control box connector pins and terminals. CCB-2 to 1HTCON1-A1 and 1HTCON1-A2 to ground. (See wiring schematic Section 10.2.) Verify there is no physical damage to harness, and no damage, moisture, or corrosion in connectors. 5. Check Evaporator High Temperature Switch (EVHTS) - Inspect for open EVHTS per wiring schematic Section 10.2. If open, replace switch as required. Alarm continued on next page... P00187 Check Heater 1 Circuit (continued) 460 VAC Circuit 6. Check Amp Draw of 1HTCON1 Heater Circuit a. With the unit running and calling for Heat, use a clamp on ammeter to check the current draw of all three legs. Must be within range shown in Section 2.10 for all three legs. b. Check fuses F39, F40, and F41 for heater elements. Verify correct fuse, check fuse holder for damage, see Figure 2.4. Replace fuse as required. Clear alarms, restart and check for repeat alarm(s). c. Check voltage at 1HTCON1 contacts. Must be within range shown in Section 2.10 for L1-L2, L1-L3, and L2-L3. Must be within range shown in Section 2.10 for T1-T2, T1-T3, and T2-T3. If not in range, verify SP-A, B, C by checking continuity from HTCON1 to GENCON d. Shut down Unit. Verify SP-A, B, C by checking continuity from HTCON1 to GENCON 7. Check Heater Elements a. Check heater elements with the unit Off. Verify there is no visual physical damage. Remove and replace if damaged. b. Check heater element resistance. Check from “T” terminals on 1HTCON1 contactor. See Section 2.10 for correct resistance. 8. Check Heater Element Connections a. Inspect high voltage heater connections at evaporator. No corrosion, water damage or burning / discoloration. Remove, repair, or replace if required. b. Disconnect heater element plug. Heater resistance per Section 2.10. Remove and replace heaters if required. c. Inspect plugs, plug seal and connectors. Verify there is no corrosion, water damage or burning / discoloration. Remove and replace if required. 9. Verify Accuracy of AC Current Sensor a. Put microprocessor in PC Mode. Refer to Section 5.3.2 page 5-8. Must have 0 AC1 Amps and 0 AC2 Amps in Unit Data. b. Use a clamp on ammeter to measure current draw of all three legs of the T side of GENCON. Meter reading should be the same as Unit Data: Compare meter reading to Unit Data in PC Mode. Compare meter reading to Unit Data with unit under load.