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The Nest thermostat delay message is a feature on a Nest thermostat that is designed to let you know that the equipment has been delayed from moving on quickly. This message usually comes up after a sudden power cut and then power comes on too quickly.
The Nest delayed message can be caused by power-sharing issues on your thermostat. This problem can be fixed by connecting a C- wire to your thermostat. Another technique that can fix this problem is adding a 220-ohm resistor to an existing Y or W wire.
A nest battery is designed to be charged by the cooling and heating wires ( Y and W) wires. But when these wires can not provide consistent power to the thermostat, this will cause a number of issues which may include a repeated ‘delayed’ message’.
Other symptoms of power-sharing issues on a Nest thermostat are outlined as follows:
In an air conditioner
- Cooling is intermittent or always on when the thermostat is not set to cool.
- Cooling is not activated when the thermostat is set to cool
In a furnace
- There is an unusual noise coming from the air heating system
- The heating does not activate when you set your thermostat to heat
- Heating is always on or intermittent when your thermostat is not set to heat
In a heat pump
- Heating or cooling is always on when the thermostat is not set to it
- The heating or cooling does not come on when you set to it
Other Causes For The ‘Delayed’ Message on a Nest Thermostat
Low battery
If the battery keeps draining frequently. This can bring about various issues with your nest including the Nest delay message. You can temporarily fix a battery that is weak by taking off the thermostat from the wall and charging it using its USB port. A Nest thermostat battery can take about 2 hours to fully charge.
Although Nest says that it doesn’t need a c-wire to work, that is not usually the case. Without a C-wire connected to a Nest, it can cause cooling and heating problems.
A nest thermostat does draw power from other wires such as RC and RH wires but that power it gets from these wires may not be enough to charge the battery. In short, the power drained may be more than the gain from those wires. That is why in many cases you might just need a c-wire connection.
However, at other times you could get a delayed message when the c wire is connected. This is because the wire could be loose or not properly connected. To troubleshoot the delayed message do this:
- Go on to thermostat settings and then tap equipment, you will see a list of all connected wires on your thermostat.
- If the blue wire is not connected you will need to have it connected.
- However, if the blue wire is connected and you are getting that error you will have to make sure it’s not loose or otherwise remove it from your thermostat.
How to fix the ‘Delayed’ Message On A Nest Thermostat
Add a C wire to the thermostat
How to add/remove c wire from nest thermostat
Remove the thermostat from the wall and check the wiring behind it. Check if the c wire is loose or if there is dirt on it. If it looks all good then you try securing the wire onto the connector of your thermostat and try to start your thermostat. This in many cases does solve the problem.
However, if you checked the wiring on your thermostat equipment settings and the C- wire doesn’t seem to be connected. Open the thermostat wiring and find the C -wire. This should be the blue wire. Connect it to the c connector and try to start your thermostat again.
However, if there is no c wire present in your thermostat wiring, there are still a few options you can take.
Option 1:
Look for the unused wire. This is an additional wire that is not connected to any connector on the thermostat and not to any terminal on the terminal block of your furnace. Take note of this wire and if possible add a tag to it for reference.
Head over to the furnace in your basement or attic and open the furnace control board. On this furnace control board, there is typically a terminal block where wires from your thermostat are attached. Look for the same unused wire that you spotted at your thermostat and label it with the same tag.
Now connect the C -wire to the c terminal on the terminal block of the furnace. If there were wires that were connected to the c terminal, just make sure that they remain connected.
Option 2: Use Nest power connector.
If there is no unused wire and a c wire is needed, there is this one more solution which is to use an adapter kit. The adapter when plugged to the furnace control board will output an additional c wire which you can use to connect to your thermostat.
The Nest Power Connector works with these Nest thermostats:
- Nest Thermostat
- Nest Learning Thermostat (3rd gen)
- Nest Thermostat E
Turn off the system by turning off your air conditioner system at the circuit breaker. (Ensure you have turned off the correct switch.
The power connector is typically installed at your furnace.
Find the control board, if you can find it, check that the thermostat wiring where connects to the air handler. Sometimes you might have more than one thermostat, in that case, install the power connector at the zone controller.
Add a resistor to an existing Y or W wire
The Nest thermostat can work without the c wire. That’s because the Nest thermostat is designed to charge the battery from the heating and cooling wires. However if these wires cannot provide consistent power, you may have to add a resistor to the Y or W terminal if connecting the C wire directly is not an optional
For furnaces, you’ll need to bridge The C terminal to the W wire at the HVAC system. A 220 volts resistor is added to prevent the control board from detecting a false call for heat or cooling.
HVAC tech with over 30 years of experience. Retired and doing repair work on the side around Madison County, AL.