iComfort variable AC
I+ / I−
I+ / I−
Lennox EL18XCV / SL28XCV. iComfort S30/S40 on I+ and I−. EL18XC1 is Y1/Y2 two-stage — different diagram.
Written circuit description only — FieldBench does not redraw maker schematics. Example: R to W closes on a heat call; verify 24V at W1 before you change the IFC.
Open manufacturer PDFiComfort communicating
S30 / S40 / communicating indoor on I+ I−.
iComfort S30 / S40
R, C, I+, I−. I+ / I− are data.
- R24V hot24V
- C24V common24V
- I+iComfort dataData
- I−iComfort dataData
Communicating indoor
Same I+ / I−. A 24V Merit indoor is the other landing.
- I+DataData
- I−DataData
- R24V24V
- CCommon24V
Variable outdoor
Communicating outdoor. No dual cap.
- I+DataData
- I−DataData
Outdoor line — inverter drive
208/230 into the drive. No contactor slam. DC bus can stay live after the disconnect.
- L1Line to the driveLine
- L2Line to the driveLine
- GNDEquipment groundLine
Landing
- DataStat I+/I−indoor I+/I−outdoor
iComfort data. Not Y.
- 24VR and C at the stat
~24 VAC
- LineL1 / L2outdoor
208/230
Prove it
- iComfort alerts first. Outdoor on the equipment list.
- I+ / I− landing and polarity. R and C still required at the stat.
Do not
- Do not use this on EL18XC1 or EL16XC1 / ML14XC1.
- Do not land Y on I+.
I+ / I− are the published iComfort communicating terminals.