We are providing information to service technicians about the new Furnace Printed Circuit Boards
(PCBs) with an enhanced flame sense signal. These PCBs will provide a higher μA signal from the flame
sensor to the PCB for better flame proving capabilities.

uA = microamp

The new uA signal is averaging about 7 with a clean flame sensor (minimum of 5). The voltage was increased about 50%. The point where the flame sensor would need to be cleaned is still 1 uA.

In addition, the following PCBs are currently in our Production furnaces as of the May 2024 serial
numbers listed below.

PCBKF105F: The first production models with this control board were DM80VC1005CN (2405354259)
and DM96VC1005DN (2405412701).

PCBKF109F: The first production models with this control board were GMVC800604BX (2405450873)
and AMVC960804CN (2405512826).

PCBKF206F: The first production model with this control board was GCVM970603BN (2405401221).

PCBBF241F: The first ULN production models with this control board were GM9S800805CU
(2405498943) and GM9S960805CU (2405439047).

PCBKF301F: The first ULN production model with this control board was GMVS800604BU (2405548826).

See Bulletin For Full Information