Hi, the previous security system used Honeywell k4274v1-h m6987.
I’m planning on removing it from the wall and attach the IQ2.
Can I power the IQ2 panel with the same electric wires? see photo attached.
I understand that it should be 12V, but I couldn’t find the wiring diagram of the Honeywell.
You can reuse the same wiring, but no, the IQ Panel 2 does not use a 12 v power supply, it uses a 7Vdc power supply.
Never reuse other older power components for the panel, only power the panel using the included plug-in power transformer.
The wiring itself can be reused depending on distance. You can double up the wires on + and - to effectively make a larger gauge and use longer cable.
18AWG cable is recommended by the manufacturer at no more than 100 feet. Thinner cable has a shorter effective range.
Json, I’m a bit confused now 
You can reuse the same wiring
from this I understand that I can use the existing wiring.
only power the panel using the included plug-in power transformer
this confuses me, if I do need the transformer, then how I can use the existing wiring? The transformer if I understand correctly, connects to a power outlet and convert 110V to the 7V.
If I need the transformer, it means that it must be connected to a power outlet.
I was hoping that I could just connect the red and black wires that coming from the IQ panel directly to the wall. Because maybe the wires I see connected to the Honeywell are already 7V.
I was hoping that I could just connect the red and black wires that coming from the IQ panel directly to the wall. Because maybe the wires I see connected to the Honeywell are already 7V.
No, it does not work that way.
The wires connecting to your old keypad are coming from the main alarm panel box. On Vistas that should be terminals 4-7. Those four terminals provide power and data transmission for the keypad.
Remove the keypad wires from those terminals.
You can reuse that wiring by cutting the transformer cable and splicing the existing wiring onto the power transformer wire to extend that wire, and I would double up conductors, which means to use two wires for + and two wires for -.
You cannot leave the wire connected to the old panel for power.
Oh ok, thanks for the explanation, I understand now.
So I could reuse the existing 4 wires that connect from the panel to the main box, disconnect them from the main box and connect them to the IQ transformer, 2 for the red and 2 for the black. The distance between the main box and the panel is about 50 feet, so I hope it’ll be fine.
In the main box, the terminals 4-7 have lots of wires. Probably due to the two panels and multiple devices wired to it. I guess I’ll need to remove one by one to see when the panel is disconnected to identify which one is connected to the panel.
Another thing, I’m thinking about now. With the current old (ADT) system, I have 3 NuTone speakers (2 in the house and 1 in the patio), when a wired sensor is activated, I hear the beep in all of them. Same for the doorbell chime, which connected to Ring.
I understand that I can’t reuse these speakers for the IQ panel. But I do want to keep the doorbell chime to be heard in all 3 speakers. So I guess only for this reason, I should keep the old main box activated and connected to the power. Otherwise, I guess I won’t have power for the speakers and they won’t be connected to Ring.
Post some photos of the control panel box and speakers ur talking about
Sure. Attached the picture of the control panel box.
I’m not at home, so can’t take picture of the NuTone chime, but it looks like this.
Hard to tell from that how the speakers are wired in. However, Ring devices are not compatible with Alarm.com.