Lennox Harmony III User Manual

12
105F
1ST STAGE2ND STAGE
TIME
2ND STAGE
Discharge Air Te mperature ºF
When the zone control system is applied to a heat pump with electric heat, the
electric heat will be staged ON to maintain the discharge air temperature set by the
heating staging jumper position.
Gasfurnacewith160°Fupperlimit(range:100-130;recommended:120).The
maximumdischargeairtemperatureatwhichthefurnacemayrunisxedat160°F.
Discharge Air Te mperature ºF
1ST STAGE2ND STAGE
TIME
2ND STAGE
Gas Furnace with 140F DAS jumper (range: 100 - 130; recommended: 120).
When the 140F DAS jumper is in place (as shown to the following illustration), the
maximumdischargeairtemperatureatwhichthefurnacemayrunisxedat140°F.
NOTE: Note the 140F DAS jumper’s impact on the differential at 120 and 130
settings.
1ST STAGE2ND STAGE 2ND STAGE
Discharge Air Te mperature ºF
1.10.8.2. Cooling Staging Temperature Jumper
Cooling Staging temperature jumpers are used to set the discharge air temperature
atwhichsecondstagecoolingcomeson.Itisselectablebetween50°,55°and60°F.
A 7 degree total differential is associated with this staging temperature, beginning
at the jumper setpoint, and extending to seven degrees above the setpoint.
Foranyjumpersetting,ifthedischargeairshouldfallto45°Fandanyzonestill
demands cooling, the compressor will not run leaving only the blower to operate
untilthedischargeaironceagainrisesto50°Fandtheveminutecompressor
OFFdelayhasbeensatised.Forthisreason,andtobettersatisfylatentloads,the
jumper recommended setting is 50.
2ND STAGE
67F
62F
57F
1ST STAGE

Lennox Harmony III Specifications

General

Brand	Lennox
Model	Harmony III
Category	Control Systems
Language	English