INSTALLATION OPERATION MAINTENANCE - Coastal Winair

Pre-startElectro Mechanical ControlsUpon power initialization, the Gas Ignition Module (IGN)performs self-diagnostic checks to insure that all internalcontrols are functional. It also checks the configuration parametersagainst the components connected to the system.The System LED located on the IGN module is turned “On”within one second of power-up if internal operation is okay.Electrocmechanical ControlsTest ProcedureSee unit schematic for correct wire numbers.Fan Test and Minimum VentilationConnect red thermostat wire (R) to black thermostat wire(G).Economizer CoolingConnect a jumper wire across OTS on Economizer Control(ECA).Connect red thermostat (R) wire to yellow thermostat wire(Y1).Cool 1Connect red thermostat wire (R) to yellow thermostat wire(Y1).Cool 2Connect red thermostat wire (R) to yellow thermostat wire(Y2).Heat 1Connect red thermostat wire (R) to brown thermostat wire(W1).Heat 2Connect red thermostat wire (R) to brown thermostat wire(W2).Verifying Proper Air Flow(Units with Direct Drive Indoor Fan)Much of the systems performance and reliability is closelyassociated with, and dependent upon having the proper airflowsupplied both to the space that is being conditionedand across the evaporator coil.The indoor fan motor is factory wired to operate on lowspeed in the cooling and high speed in the heating mode. Itcan be rewired for high speed operation should the applicationrequire it. Refer to the wiring diagram that shipped inthe unit.The indoor fan motors are specifically designed to operatewithin the BHP parameters listed in the fan performancetables of the unit Service Facts. By understanding that thesemotors will safely work within these conditions, before anoversized motor is required, will allow the air distributionsystem to be set up properly and diagnostics enhancedshould a problem occur.When verifying direct drive fan performance, the tables mustbe used somewhat differently than those of belt driven fans.Fan performance diagnostics can be easily recognizedwhen these tables are used correctly.Before starting the SERVICE TEST, set the minimum positionsetpoint for the economizer to 0 percent using thesetpoint potentiometer located on the Economizer Control(ECA), if applicable.ReliaTel ControlUsing the Service Test Guide in Table 6, momentarily jumpacross the Test 1 & Test 2 terminals on LTB1 one time tostart the Minimum Ventilation Test.Electro Mechanical ControlUsing the Service Test Guide perform the proper test modeconnections.With the fan operating properly, determine the total systemexternal static pressure (inches w.c.) by;1. Measuring the supply and return duct static pressure,2. Using the accessory pressure drop table in the ServiceFacts, calculate the total static pressure drop for all of theaccessories installed on the unit; i.e., curb, economizer,etc.Note: Static pressure is based on desired CFM andmay not be actual static pressure.3. Add the total accessory static pressure drop (step 2) tothe duct external static pressure (step 1). The sum ofthese two values represents the total system externalstatic pressure.4. Measure the amperage at the supply fan contactor andcompare it with the full load amp (FLA) rating stamped onthe motor nameplate.a. Calculate the theoretical BHPActual Motor Amps X Motor HPMotor Nameplate Ampsb. Using the fan performance tables in the unit ServiceFacts, plot the total external static pressure (step 3)and the BHP (step 4a) to obtain the operating CFM.c. When plotted, if the two values can not beinterpolated correspondingly, the static pressure willmost likely be the least accurate measurement.Because of the direct drive motor operation, the RPMperformance is relatively constant making theoperating current a very reliable diagnostic tool.Example:T_D060 single phase, low speed.Actual Motor Amp (5.25) = .99%Motor Nameplate Amps (5.3)0.99 X Motor HP (0.6) = .59 BHPThe actual external static pressure is approximately0.45” w.c., airflow equals 2100 CFM.If the static pressure reading was higher, motorcurrent would have to be lower proportionately to getan accurate CFM measurement in direct driveapplications.33