Nest thermostat, heat pump with dual fuel boiler backup problems

[PeterB3]

I have (Two) gen 3 nest learning thermostats, a new Ecoer heat pump and a gas fired hot water backup system. I have checked and double checked all the connections and still am not able to get things working properly. I have Y1, Y2, O, G, Rh, W1, and C connections. The thermostat is configured for 2 Stage heat pump and gas boiler backup. Running tests I get fan but no heat from the heat pump and heat but with the fan (unwanted) running in the backup boiler mode. The heat pump works with the thermostat disconnected and the Y1 ,R and G jumped together. I’ve switched out both of my thermostats and backing plates and gone through all the setup options I can find and still can’t get things to work right. Anybody have any suggestions?

[CoolingWizard]

@PeterB3 ,

You say that you have a heat pump do you know if it is an O-type or a B-type? Why do you have 2 Gen 3 Nest Learning Thermostats? Is the ECOR a separately controlled heat pump from your hot water heater/baseboard heating system?

Since you say you heat pump is a 2-stage system, your Y1 and Y2 are your first and second stage.  The OB connection activates the outdoor unit changeover valve.  It is this changeover valve that switches it from heating to cooling or from cooling to heating. If this OB wire is not set up properly when you run it as an air conditioner, it will put out hot air and as you run it as heat, it will put out cold air. If that is the case, you need to go into your equipment, setting and change it from an O type unit to a B type unit.

If your hot water system is indeed your backup system. The control of that system either needs to be wired to W2 To function as auxiliary heat, or you need to define it as a dual fuel system, and then have the heating secondary system controlled by W1. However, if you have not defined the system as a dual fuel system, W1 will not activate any kind of heat.  

I am pretty sure you need to find your system as a dual fuel system since the hot water system is a gas fired furnace, which is separate from the heat pump. When you define a dual fuel system, you must pick a point in energy cost to switch from the primary heat of the heat pump to the secondary heat of the baseboard hot water heating system. 

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AC Cooling Wizard

[PeterB3]

Thanks for the reply. I have two Nest’s because a few years ago I thought my nest had gone bad and I ordered a replacement. I fixed the problem before connecting the new one. Only one is used in my system. 

The Ecoer is a separate heat pump that recently replaced my old ac system. It uses O setup. My original heat source is hot water radiators and it has now become backup in a dual fuel setup. The nest is set up as dual fuel and all the connections are verified through the pro setup settings. The switch over temperature is currently set high enough that the heat pump should activate. 

Please let me know if you come up with any ideas!  Thanks.