High efficiency gaz furnace won't stop

[Mike222]

I have just install a Nest Learning Thermostat.

I have hot water radiator

The temperature was set at 65F for the night. It was 74F when I woke up and kept going up.

The high efficiency furnace was running at low gaz input (30%), the pump just kept running.

I turned the power off and on but did not change a thing.

I putted the thermostat at econo 60F, but the pump was still running

I have 2 wires: W and RH

Help!

[Patrick_Caezza]

@Mike222 

Do you have a dual heating system?

Hot water radiators require a boiler and a gas furnace supplies hot air.

What is the Nest thermostat connected to?

Does the pump turn off if you disconnect the Nest?

[Mike222]

@Patrick_Caezza 

I don't have a dual heating system. It's a gas boiler.

The thermostat is conected directly to the furnace

I just tried to remove the Nest thermostat and the furnace is still running (I shot down the furnace for the night and just turn it on to do the test. The temperature is still set at eco 60F to make sure, that the furnace is not suppose to work). The Nest shows that the batterie is low.

Thanks for your help

[Patrick_Caezza]

@Mike222 

Boilers are a pain to set up for use with any smart thermostat correctly. You're going to need the Nest Power Connector and an external 24vac transformer.

[Mike222]

@Patrick_Caezza 

Hi Patrick,

I would be able to attache a third wire from the thermostat to the furnace.

I guess that no matter what, I will still need the Power connector, right?

Where would I plug the 3rd wire on the furnace, see the picture below.

Thanks for your support

[Patrick_Caezza]

@Mike222 

I don't see anywhere to connect a third wire. That's why you will need the external 24vac transformer.

[Mike222]

@Patrick_Caezza 

Your diagram with the extranal 24v transformer are not to clear.

I was not able to find the manual with that wiring on the WEB.

Can you send me a link our a copy of that manual by email

#

Thanks 

[Mike222]

@Patrick_Caezza 

I have ordered the Nest Power Connecter that I shoud be receiving in the next few days.

I have seen the video "How to install", no issues for that.

But I still wondering abourt the 24v transformer. 

[Patrick_Caezza]

@Mike222 

Here is a link to the Google Nest Help article about the Nest Power Connector.

Nest Power Connector 

At the bottom, you will find links to the different installation guides.

[Mike222]

@Patrick_Caezza 

Good, I found the right installation guide.

Will let you know in a few days when I have received the power connector

Thanks

Have a nice day

[Mike222]

@Patrick_Caezza 

I have finalized the installation yesterday morning. It's finally working with Nest power connector and the 24 V transformer.

Thanks for your help

[Patrick_Caezza]

@Mike222 

Good to hear