York SUNLINE MagnaDRY DR180 Installation Manual

Also see for SUNLINE MagnaDRY DR 180: Submittal data sheet Installation manual

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York SUNLINE MagnaDRY DR180 Installation Manual Manual pdf 70 page image

127915-YIM-A-040570 Unitary Products Group8. If 24 volts are present at the UCB Y1 terminal, thecompressor may be out due to an open high-pres-sure switch, low-pressure switch, or freezestat.Check for 24 volts at the HPS1, LPS1, and FS1terminals of the UCB. If a switch has opened, thereshould be a voltage potential between the UCB ter-minals, e.g. if LPS1 has opened, there will be a 24-volt potential between the LPS1 terminals.9. If 24 volts is present at the UCB Y1 terminal andnone of the protection switches have opened, theUCB may have locked out the compressor forrepeat trips. The UCB should be flashing a code. Ifnot, press and release the ALARMS button on theUCB. The UCB will flash the last five alarms on theLED. If the compressor is locked out, remove anycall for cooling. This will reset any compressor lockouts.NOTE: While the above step will reset any lock outs,compressor #2 will be held off for the ASCD,and compressor #1 may be held off for a por-tion of the ASCD. See the next step.10. If 24 volts is present at the UCB Y1 terminal andnone of the switches are open and the compressoris not locked out, the UCB may have the compres-sor in an ASCD. Check the LED for an indication ofan ASCD cycle. The ASCD should time out within5 minutes. Press and release the TEST button toreset all ASCDs.11. If 24 volts is present at the UCB Y1 terminal andthe compressor is not out due to a protectiveswitch trip, repeat trip lock out, or ASCD, the econ-omizer terminals of the UCB may be improperlywired. Check for 24 volts at the Y1 “OUT” terminalof the UCB. If 24 volts is present, trace the wiringfrom Y1 “OUT” for incorrect wiring. If 24 volts is notpresent at the Y1 “OUT” terminal, the UCB must bereplaced.12. For units without economizers: If 24 volts is presentat the Y1 “OUT” terminal, check for 24 volts at theY1 “ECON” terminal. If 24 volts is not present,check for loose wiring from the Y1 “OUT” terminalto the Mate-N-Lock plug, the jumper in the Mate-N-Lock plug, and in the wiring from the Mate-N-Lockplug to the Y1 “ECON” terminal.For units with economizers: If 24 volts is present atthe Y1 “OUT” terminal, check for 24 volts at the Y1“ECON” terminal. If 24 volts is not present, checkfor loose wiring from the Y1 “OUT” terminal to theMate-N-Lock plug, a poor connection between theUCB and economizer Mate-N-Lock plugs, loosewiring from the Mate-N-Lock plug to the econo-mizer, back to the Mate-N-Lock plug, and from theMate-N-Lock plug to the Y1 “ECON” terminal. Theeconomizer board may have faulted and is notreturning the 24 volts to the Y1 “ECON” terminaleven though the economizer is not providing freecooling. To test the economizer board, disconnectthe Mate-N-Locks and jumper between the WHITEand YELLOW wires of the UCB’s Mate-N-Lockplug.13. The UCB can be programmed to lock out compres-sor operation during free cooling and in low ambi-ent conditions. These options are not enabled bydefault. They can be checked by local distributors.14. If none of the above correct the error, replace theUCB.GAS HEAT TROUBLESHOOTING GUIDETroubleshooting of components may requireopening the electrical control box with thepower connected to the unit. Use extremecare when working with live circuits! Checkthe unit nameplate for the correct line voltageand set the voltmeter to the correct rangebefore making any connections with line termi-nals.When not necessary, shut off all electric powerto the unit prior to any of the following mainte-nance procedures so as to prevent personalinjury.Label all wires prior to disconnection when ser-vicing controls. Wiring errors can causeimproper and dangerous operation, whichcould cause injury to person and/or damageunit components. Verify proper operation afterservicing.