11-23-2023 06:28 AM
Hello,
I have an old furnace and wired the power connector as follows:
https://photos.app.goo.gl/wUPCJe8V7ECGcSH26
Everything seems to work (V and I readings on Nest are within range) until the furnace kicks in to provide heat, at which point the voltage and amperage go to zero. Now I'm not entirely sure because I couldn't find the labels but I believe the box on the right is the 24V transformer. As can be seen from the image, the original configuration was:
- W from thermostat to gas valve
- R from thermostat to transformer
- ? from transformer to gas valve. I think this is C
I then added the power connector so it is:
-W from thermostat to Power Connector. W from Power Connector to gas valve
-R from thermostat to Power Connector. R from Power Connector to transformer
-3-way splice of C from Power Connector, ? from Transformer and a wire leading to gas valve
-Jumper insert inside connector still inside
Does anybody know why V and I go to 0 when the furnace starts?
Answered! Go to the Recommended Answer.
12-13-2023 03:05 AM
Turning off Nest motion sensing, the beep sound, and "turn on upon approach" seems to have solved the problem. Maybe the 24V transformer doesn't have enough for all these features.
11-26-2023 07:11 AM
Hi UrbanHermit,
Thanks for reaching out to us, and I'm sorry to hear that the power readings of your thermostat dropped to 0 after installing the Nest Power Connector. If the voltage (V) and current (I) readings drop to zero when the furnace starts, it indicates that there may be an issue with the electrical connections or the circuit itself.
Double-check all the wiring connections you made during the installation process. Make sure that the connections are secure, properly insulated, and correctly matched to their respective terminals. Verify that there are no loose connections or frayed wires that could be causing a disruption in the circuit. As the furnace starts to draw more power, a voltage or current drop can be caused by a short circuit. Check the relay and transformer electrical components appropriately for the load they handle. In the event of a bad transformer or relay, ensure the voltage requirements are within range for the furnace. Try testing the components individually or using alternates to diagnose faults. The power connector and other components must be compatibly selected, depending on the specific furnace model and wiring setup. The circuit breakers or limit switches should be checked to see if they have been activated and to find out the reason. Follow the Nest Power Connector installation guide in this article for more details.
Let us know how it goes.
Best,
Zoe
12-13-2023 03:05 AM
Turning off Nest motion sensing, the beep sound, and "turn on upon approach" seems to have solved the problem. Maybe the 24V transformer doesn't have enough for all these features.
12-13-2023 12:41 PM
Hi there UrbanHermit,
Thanks for the update! I'm glad to hear that the issue seems now resolved. I suggest to continue monitoring it, and if anything comes up just feel free to let us know, as we'll be willing to assist you further.
I appreciate your input, Zoe.
Cheers,
Jenelyn