I purchased a new Nest 3rd Gen learning thermostats and as soon as I connect the two wires (white and red wires) to the respective contacts, the heat for that zone turns on. This happens when connected to any of the 3 zones in my house. I chatted with Nest support the other day and they verified compatibility with my heating system which is a 7 year old Peerless Boiler model WBV-03-WPCL. I had my boiler service company come out and he felt the Nest backing plate was defective. However, he tried two different non-nest thermostats and had the same result, calling for heat when it should t be. He then tried a 3rd thermostat, a Honeywell programmable and it worked. However, I wanted Nest since I am using all Nest products in the rest of the house (cameras, doorbell) and want to control with one app. The tech could not explain why he also had problems with two of his thermostats, but maintained the Nest must be defective. I ordered another Nest and installed the two wires to the backing plate and once again, zone called for heat when it shouldn’t and will not turn off. I tried the same new backing plate in another zone and got the same result. So am pretty sure the Nest is not defective, but there has to be some compatibility issue. Have searched everywhere for clues, but not finding any. Hoping someone here has some experience with this and can help. Thanks in advance.