Installation Operation Maintenance

OperationReliaTel is a microelectroniccontrol feature, which providesoperating functions that aresignificantly different fromconventional electro-mechanicalunits. The master module is theReliaTel Refrigeration Module(RTRM).The RTRM provides compressorantishort cycle timing functionsthrough minimum "Off" and "On"timing to increase reliability,performance and to maximize unitefficiency.Upon power initialization, the RTRMperforms self-diagnostic checks toinsure that all internal controls arefunctioning. It checks theconfiguration parameters againstthe components connected to thesystem.The LED located on the RTRMmodule is turned "On" within onesecond after power-up if all internaloperations are okay.Cooling without anEconomizerWhen the system switch is set tothe "Cool" position and the zonetemperature rises above the coolingsetpoint controlband, the RTRMenergizes the (K9) relay coil locatedon the RTRM. When the K9 relaycontacts close, the compressorcontactor (CC1) coil is energizedprovided the low pressure control(LPC1) and high pressure control(HPC1) are closed. When the CC1contacts close, compressor (CPR1)and the outdoor fan motor (ODM)start to maintain the zonetemperature to within ± 2 F of thesensor setpoint at the sensedlocation.If the first stage of cooling can notsatisfy the cooling requirement, theRTRM energizes the (K10) relay coillocated on the RTRM. When the(K10) relay contacts close, thecompressor contactor (CC2) coil isenergized provided the lowpressure control (LPC2) and highpressure control (HPC2) are closed.When the CC2 contacts close,compressor (CPR2) starts tomaintain the zone temperature towithin ± 2 F of the sensor setpointat the sensed location.Evaporator Fan OperationWhen the fan selection switch is setto the "Auto" position, the RTRMenergizes the (K6) relay coilapproximately one second afterenergizing the compressorcontactor coil (CC1) in the coolingmode. In heating mode, the RTRMenergizes the (K6) relay coilapproximately 45 seconds after gasignition. Closing the K6 contacts onthe RTRM energizes the supply fanrelay (F) coil to start the supply fanmotor (IDM).The RTRM de-energizes the fanrelay (F) approximately 60 secondsafter the cooling requirement hasbe satisfied to enhance unitefficiency.When the heating cycle isterminated, the supply fan relay (F)coil is de-energized approximately90 seconds after the heatingrequirement.When the fan selection switch is setto the "On" position, the RTRMkeeps the supply fan relay coil (F)energized for continuous fan motoroperation.When the unit is equipped with theoptional clogged filter switch, wiredbetween terminals J7-3 and J7-4 onthe ReliaTel Options Module(RTOM), the RTRM produces ananalog output if the clogged filterswitch (CFS) closes for two minutesafter a request for fan operation.When the system is connected to aremote panel, the "SERVICE" LEDwill be turned on when this failureoccurs.56RT-SVX20B-E4