When using a millivolt thermopile generator in a gas furnace, what should be avoided regarding thermostat wire?

When utilizing a millivolt thermopile generator in a gas furnace, it's essential to ensure that the thermostat wire is kept to an appropriate length, as excessive wire length can lead to voltage drop and reduced efficiency. Millivolt systems are designed to operate at low voltages, and any significant increase in wire length can introduce resistance, which affects the power supplied to the thermostat and potentially compromises the operation of the gas valve or the entire heating system.

Keeping the wire length as short as feasible helps maintain adequate power levels and ensures a reliable signal is sent from the thermostat to the furnace. This is particularly crucial in systems relying on thermopile generators, where voltage output is already limited. By maintaining a suitable wire length, you are supporting the optimal functioning of the heating system, ensuring that it responds effectively to thermostat settings.