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Wifi Thermostat

Tony Massi
Tony Massi Member Posts: 86
I'm looking for a Wifi thermostat that uses only 2 low voltage wires to run a boiler on zone valves.
Most of the thermostats I have seen use three. I only have 2 wires running the thermostat.

Comments

  • ChrisJ
    ChrisJ Member Posts: 13,911
    http://www.supplyhouse.com/Honeywell-YTHX9421R5127WW-Prestige-IAQ-Thermostat-Kit-w-RedLINK-Internet-Gateway

    You won't need the two duct sensors, but the rest will work just fine.

    Thermostat is powered via 2 wires, that don't even necessarily have to come from the boiler room, but can. For your app I'm assuming those two wires will connect the thermostat head to the EIM controller, which you will locate where convenient to run your new wires. For example, right by the zone valves.

    They also sell a wireless outdoor sensor so the thermostat will show outdoor temp and humidity. It can use up to something like 6 indoor wireless sensors to average temp across multiple rooms, if you want, or just the single thermostat like normal.

    This, in my opinion, is the best of the best when it comes to thermostats and all it needs is two wires.


    Here's the outdoor wireless sensor.
    http://www.supplyhouse.com/Honeywell-C7089R1013-RedLINK-Enabled-Wireless-Outdoor-Sensor

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Tony Massi
    Tony Massi Member Posts: 86
    Thanks for the response. I'm looking for a thermostat only in your opinion which one would you think would be best for this application.
  • ChrisJ
    ChrisJ Member Posts: 13,911
    edited September 2017

    Thanks for the response. I'm looking for a thermostat only in your opinion which one would you think would be best for this application.

    That is only a thermostat, it's just split into a few pieces.

    The "works" go in the basement, or wherever the equipment is. The head, goes where your thermostat is. No more clicking relays, no extra wires to run. The internet gateway goes where ever it's most convenient to plug into your internet and communicates with the rest wirelessly.

    You don't need the outdoor sensor if you don't want it, and the two duct sensors that come with it don't need to be used, just throw them aside.


    I know, it seems intimidating because it's in pieces, but it's not bad and it really is exactly what you're asking for. A good WIFI thermostat that only needs two wires. Though, it's internet connection will be hard wired.

    it behaves very much like a Honeywell VisionPro. Very easy to use and you can customize the screen colors if you want.


    Outside of this, I don't know of any other WIFI/Internet thermostat that doesn't need more than two wires.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Robert O'Brien
  • ratio
    ratio Member Posts: 3,338
    What are you trying to control, two-wire zone valves? How many?
  • Tony Massi
    Tony Massi Member Posts: 86
    Yes one V8043E zone valve
  • HVACNUT
    HVACNUT Member Posts: 4,873
    @Tony Massi. The V8043E is a 4 wire ZV.
    @ChrisJ. Just asking. Does an isolation relay need to be installed to close TT on the boiler? The end switch in the ZV wouldn't be used?
    The wiring diagrams only show using the "U" dry contacts in a GEO, or accesories application, if I'm reading it right. Can the thermostat be programmed to close a set of U contacts on a heat call?
  • ratio
    ratio Member Posts: 3,338
    It sounds like the OP wants to replace an old heating-only snap stat with something WiFi enabled. If that's the case, a Honeywell 6320WF will give you programmability and WiFi. It does, however, require a common, a 3rd wire from the transformer that isn't always present with the older stats. A RedLINK 6320 can be run from batteries, however you will need additionally a RedLINK internet gateway to allow remote access to it.
  • Tony Massi
    Tony Massi Member Posts: 86
    To make things easier I ran a new five wire thermostat wire to the old thermostat
    ChrisJ
  • ChrisJ
    ChrisJ Member Posts: 13,911

    To make things easier I ran a new five wire thermostat wire to the old thermostat

    That works too.
    Funny thing.............I replaced a 4 wire with a 7, but then that wasn't enough so I went to an 8, and then some how ended up with the Prestige that only needs 2.


    The story of my life.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Canucker
  • krimm
    krimm Member Posts: 3
    ecobee would have been nice but it runs on more than 2 wires. I like that it supports Alexa but it's too costly though, yayks!