Showerthought: I used to skip the resistor on EOL zones, then a panel in Gary showed me why
I used to wire end of line zones straight through and call the resistor a waste of time, just something the manual nagged about. Then I did a job in Gary, Indiana, 16 zone panel, and a guy who has been doing this 20 odd years watched me do it and asked me to add the resistor on one door just to see. Two days later the customer called about a zone fault that only popped up when the AC kicked on, and that one resistor killed the noise dead. Now I keep a bag of 2.2k resistors in the truck and I throw them on every EOL, even on a quick swap. Anybody got a zone that stayed flaky even with the resistor in place?