Don Foreman wrote:

Even the venerable Honeywell
"round" (T-87), which has been around for over 50 years, did and does
a surprisingly good job of this by virtue of it's anticipator --
which almost nobody outside of their engineering org really completely
understood.

Did the old standing pilot type furnaces tend to draw about the same current from one
model to another to turn the burner on? I always thought it was clever getting a bit of
heat via resistance to 'anticipate' when to turn off the burner.

Wes