My Honeywell M847D1012 Actuator was making a clicking sound (once per second ish) when the damper was in power close position. This product Honeywell M847D Zone is a direct replacement. Total work took < 30 minutes.
After I removed and dissembled the actuator, I realized the issue was caused by a stripped plastic gear inside the old actuator. The gear was not hard to remove - I could’ve probably just replaced the gear instead of buying a new actuator. However the gear was unlabeled and unbranded. It may be hard to find.
Actuator replacement process:
Equipment:
1. Honeywell M847D Zone Valve Actuator
2. 3/16 hex key (allen wrench, t-handle, etc. Any works - you need this to loosen/tighten a set screw)
3. long nose plier (or any tool with a pointy tip. You need this to push down the buttons on the new actuator to push the wires in.)
4. non-contact voltage meter (eg. Klein Tools NCVT-3, when you turn the power off on the actuator / your furnace, before you remove the old actuator, you want to use this to touch the wires connecting the old actuator to make sure there’s no power. It’s 24V, may not be the worst even if you touch it, but preferably don’t touch live wire.)
Guide:
1. Youtube. Andrew Rogers, How to Change an AC Damper Motor. Very clear step-by-step process. https://www.youtube.com/watch?v=KsmNq4tccPY
2. Medium. Ninu, How to swap out an HVAC damper actuator yourself - Honeywell M847D-ZONE. https://medium.com/@ninu/how-to-swap-out-an-hvac-damper-actuator-yourself-honeywell-m847d-zone-c99d25ca3167
3. SupplyHouse. Has > 100 useful reviews. https://www.supplyhouse.com/Honeywell-M847D-ZONE-TRUEZONE-Replacement-Actuator-for-Normally-Open-Dampers
4. Search Term: “Honeywell actuator replacement”
5. My issue was “Failed zone damper” with clicking sound, sample video from Dennis Benjamin https://www.youtube.com/watch?v=V5zQ4UQ9Iks
Some hiccups:
1. The box I got from Amazon came with a little packet of 2 set screws. One is 0.5 inch long and has a head. The other is 1.5 inches long and is a headless / socket / blind set screw. You can use either one as the set screw, or use the old set screw (1.5 inch, has a head) from the old actuator. I prefer the old set screw because it is longer, so it is more visible and my Allen wrench can reach it more easily. It also has a head so I can grab it with my fingers.
2. You should use the non-contact voltage meter to test and ensure power is off before you start removing the old actuator.
3. How to determine which wire goes to M1, M4 and M6? The short answer is whatever wire that was connected to the old actuator’s orange wire should be shoved into M1. Whatever wire that was connected to the old actuator’s yellow wire should be shoved into M6. The long answer is: I’m not using M4 (for LED indicator light). I use M1 (for common wire) and M6 (for 24 Vac wire). It seems that for AC, you can switch the wires, but it’s a good habit not to. I assumed the old actuator was wired correctly. Eg. I have two wires connecting to the old actuator’s orange wire and yellow wire respectively. say, Wire-1 —> Old Actuator Orange Wire —> M1. Wire-2 —> Old Actuator Yellow Wire —> M6. I based this on “Andrew Rogers”’s youtube guide). It works correctly in my case.
4. You may need to wiggle the wires to make them fit in M1 and M6, especially because the original wires came out twisted once you remove the wire connectors. You can use the plier to straighten the wires a bit before shoving them in M1 and <6.
5. Short wires? Beware that the wires from your home might be a bit short and might not reach the new actuator, since the new one doesn’t have connecting wires, but just buttons. You can pull on your wires to see if you can make it reach the new actuator.
6. The set screw on the old actuator may be hard to unscrew - it might be very tight. Use some force to loosen it.
Steps:
1. prepare the tools
2. make sure you know which wires should go into M1 and M6 ahead of time (See hiccup #3)
3. put the set screw onto the actuator just right - make sure you can’t see threads from inside the actuator hollow central pin, so that there’s enough space in the hollow pin to connect to the pin coming out of the damper)
4. turn power off of the furnace and the zone control (from main service panel)
5. make sure furnace won’t call for heat (this should be true since power is turned off on the furnace)
6. use non-contact voltage meter to test for no voltage on the wires coming out of the actuator
7. make sure the fan is off - no blowing air. This should be true already since the furnace is off. But just double check. If the fan were on, it may blow the damper off, no good.
8. loosen but don’t unscrew the set screw (the long screw towards the bottom right) on the old actuator. It may require some force to loosen it. If you look at the set screw head, then clockwise is to unscrew.
9. unscrew the two wire connectors and untwist the wires.
10. push the hex key to further loosen and remove the hex screw on the old actuator
11. put the set screw aside. You can use this instead (see step 2) on the new actuator, or not - your preference (See hiccup #1)
12. remove/pull the old actuator in a straight outward manner
13. check the damper is open all the way (may be hard if you don’t have opening in the duct. If that’s the case, ignore this step - your damper should be open all the way anyway, since it’s always open and power close)
14. observe the hollow central pin and the stationary pin on the new actuator
15. push the new actuator straight on
16. check the new actuator indicating it’s in the “open” position
17. tighten the set screw (it should already be on the new actuator by step 3). Tighten it all the way.
18. damper should show it’s completely open.
19. hook up the wires: M1 (common/ground) with the wire that originally connected to the orange wire on the old actuator. And M6 (24V) with the wire that originally connected to the yellow wire on the old actuator.
20. push the wires in
21. push the M1/M6 buttons down one by one. Push it down, put wire in, let go of the button, give it a wiggle to make sure the wire doesn’t come out. You should be able to shove 1/6 inch of the wire inside at least.
22. turn power back on
23. watch your actuator move when heat is called.
Ryan Zabka