r/ecobee • u/CA2DC99 • 4d ago

Ecobee Variable Speed HVSC Compatibility

I have a newer variable speed Carrier HVAC system. When they installed it, they told me my existing Ecobee thermostat was not compatible. This was a couple years ago. I hate the compatible thermostat they gave me, and I still have my other Ecobee thermostat running the main floor and basement. So I’m checking to see if Ecobee has released any recent products that are now compatible with variable speed HVAC units.

8 Upvotes

84% Upvoted

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7

u/ChasDIY 4d ago

Ecobee is probably Compatible

It just doesn't handle communication to take complete advantage of variable speed inverters

I am using one with my Bosch Premium IDS heat pump and don't notice anything missing

5

u/Pielet2 4d ago

I agree with this, although the Bosch system is configured a little differently than the carrier Infinity. The Bosch unit takes all its own measurements to determine compressor speed so they can be installed with almost any air handler. Infinity systems speed up or slow down the indoor blower along with the outdoor compressor and fan motor to maintain temp and humidity. It's been awhile since I've worked with an Infinity system, but they usually can be wired up as a two-stage with a standard 24 volt thermostat like ecobee. You just won't get the full variable speed, and you won't get the longer run times to strictly dehumidify which is more helpful than people realize.

-2

u/ChasDIY 4d ago

I think you just said what I said

1

u/Pielet2 3d ago

Kinda. The main thing is that the Bosch still maintains its true variable speed while the carrier will only run as a (maybe) two-stage if it's wired to an ecobee.

1

u/bites_stringcheese 4d ago

How is the Bosch IDS? My twin carrier heat pumps are 24 years old and still going strong with motor and capacitor replacements, but not for much longer.

2

u/pandaman1784 4d ago

Keep using them until something expensive breaks. 

2

u/bites_stringcheese 4d ago

I plan on it. I try and keep the coils clean, and use low MERV filters.

2

u/ChasDIY 3d ago

the problem with that approach is it will fail when you need it most and may take some time to organize replacement with HVAC firm

best to research now and decide on the one you want and ask for at least 3 quotes

then you are ready at the slightest hint of failure

2

u/bites_stringcheese 3d ago

You're right and even sourcing a new motor locally was a PITA. I would like to at least have an idea of brand/model/size to save any potential downtime.

That being said, they're still working great, even in hot NC summers.

1

u/ChasDIY 3d ago

👍

1

u/ChasDIY 3d ago

excellent, as the inverter makes it seamless at temp mgmt and maintenance

4

u/jam4917 HVAC Pro 4d ago

Short answer no. The ecobee is a conventional thermostat while your Carrier requires a communicating thermostat.

Long answer - there are specific variable speed units that will work with a conventional thermostat like an ecobee. Bosch and Daikin, among others, make them.

4

u/MyNamelsJ3ff 4d ago

I can confirm my variable speed Bosch IDS 2.0 works with the Ecobee.

3

u/OldPossibility2691 4d ago

Carrier makes an ecobee for their products.

2

u/pandaman1784 4d ago

It's actually the other way around. Ecobee makes a product for carrier. 

1

u/Thin_Caterpillar6998 4d ago

This! One was installed with my new unit last week.

3

u/danh_ptown 4d ago

While this can be done, OP, it reduces the efficiency and beauty of that fully variable speed system. The thermostat has additional measurements that it takes of the room and sends that information to the control board. It is a sophisticated thermostat, just completely proprietary.😠

In your situation, just make do. It's an expensive proposition to convert it to 2-stage as you have to hire a tech to do it. Make the changes test it out, etc... then you/they deal with complaints when humidity is different and the house feels different.

When you replace the system, then you can look for alternatives. For me, the thermostat was #1 in importance, and I required an Ecobee thermostat. I chose the Bosch system which is a 2-stage fan system with variable speed condenser, and works with generic thermostats, like Ecobee.

To get around the same problem, that Carrier solved with the communicating thermostat, Bosch designed a system based on sensors. It determines how much cooling is needed to maintain coil temp at current fan speed etc.... This gives the system a sense of room conditions without actual sensors in the room. The Ecobee is essentially limited to On/Off and Fan Speed 1 & 2, in communicating with the system.

2

u/kstrike155 4d ago

Largely depends on what your specific Carrier system is, but short answer is no. If you want true variable speed, ecobee doesn’t support it.

Some systems allow the air handler to determine the fan speed automatically without involvement from the thermostat, but even then it’s a “best guess” effort.

You might be able to do two-speed fan control (ecobee supports it) and I find that is sufficient for my needs.

2

u/Warbird01 4d ago

If it’s an Infinity system, you don’t want an Ecobee even if it were compatible. The infinity stat’s might have a terrible UI, but provides the communication needed for the infinity system

2

u/CaminoRubicon1 4d ago

If you want a single or two stage system, why did you spend all that extra money for an elite system? Yes, the Carrier will run on a 24V thermostat but staged. You will be missing out on all the comfort and dehumidification advantages of a VS system.

I don't know what vintage of stat u have but Carrier may have a newer one that has more customer features you desire.

2

u/fieldguild 4d ago

Unfortunately, you generally have to stick with the manufacturer's thermostat. There aren't really third party communicating thermostats, with a few rare exceptions like Airzone.

I shared some data from a California utility, SMUD recently that showed a >25% difference in energy use going with the manufacturer’s communicating thermostat versus a conventional thermostat like an Ecobee, plus substantially better modulation meaning that you’ll better take advantage of the variable speed benefits of your heat pump (about halfway down this article here: https://www.heatpumped.org/p/summer-2026-group-buy-equipment-update)

For our installs, we’ve standardized on only using the manufacturer’s communicating thermostats for this reason unless there are extenuating circumstances that would necessitate a third party model

What model of Carrier system do you have? If it's one of their Midea re-badged models (38MURA for example), you might be able to upgrade the thermostat to their newer communicating thermostat which is leaps and bounds better than the crummy thermostats that they had been offering for a while: https://www.carrier.com/us/en/residential/ductless-mini-splits/ksacn1701aaa/

2

u/echoota 4d ago

I'm in the exact same situation. the EcoNet is annoying AF when it keeps forgetting the wifi password. I found this Ecobee listing on the carrier site.

https://www.carrier.com/us/en/residential/smart-thermostats/eb-state6icr-01/

But when I asked my Carrier installer, another installer from the carrier site, and Ecobee themselves, they said that I would lose the variable speed functionality.

3

u/pandaman1784 4d ago edited 4d ago

Yes, you will lose functionality. The only difference between the ecobee that carrier sells and the one ecobee sells is that Carrier version can accept the data communication from the equipment carrier intellisense feature. 

2

u/echoota 4d ago

That's more explanation then i got from anything the 3 people i made contact with. So thank you for the info, much appreciated!