TRANE Thermostat EHEAT Mode

Other Devices & Integrations Climate Control & Temperature Sensors
1

I’ve tried to figure this out but now that we are in Cold Weather season, I really need a solution to this.

I have a Hybrid Gas/Heat Pump system and I need to be able to set the Trane to use the EHEAT mode from Vera2 (that is selectable from the main screen on the Trane).

Is there a Parameter that can be set in the Trane from Vera to select this mode? My goal is to have a script that triggers on outside temp. to set EHEAT mode when the temp drops below 35F and set back to AUTO when temp rises above 35F. EHEAT mode is needed to lockout the HeatPump Compressor.

2

I would love the answer too…

Anyone?

I just ordered it, and will be installing it shortly. Hope we can find the answer!

3

I was wondering if anyone ever figured this out. I have the same situation, and electric heat pump and an electric furnace.

4

A feature request was submitted on my behalf over a year ago.

It appears to have been assigned but no movement yet.

http://bugs.micasaverde.com/view.php?id=1950

Sent from my SPH-D710 using Tapatalk 2

5

Not all thermostat functionality is available through the Zwave protocol. Also not all trane thermostats support the same functionality. For example my trane thermostat does not support changing to energy mode, but newer versions do.

  • Garrett
6

[quote=“garrettwp”]Not all thermostat functionality is available through the Zwave protocol. Also not all trane thermostats support the same functionality. For example my trane thermostat does not support changing to energy mode, but newer versions do.

  • Garrett[/quote]

If the mode was not supported, then would the thermostat just ignore the command?

Not all thermostats support Fan Cycle I expect but that appears to be in UI5. My 2gig ct-30 doesn’t support fan cycle but that option appears in the UI.

Sent from my SPH-D710 using Tapatalk 2

7

Most likely. Since the protocol is not supported for the thermostat. The ui shows basic controls for the thermostat even if an option is not supported.

  • Garrett
8

I think it’s a mixed bag of why certain functionality isn’t there: Vera may not support it (e.g.: e-heat), the t-stat FW changed (e.g.: fan cycler; looks like a mapping issue, older t-stat FW will not work with Vera UI), the t-stat FW doesn’t support it (possible example: apparently @garrettwp’s doesn’t support ESM through the UI).

The Trane I use for testing is FW 01.00.13; ESM works through the UI; fan-cycler does not.

@vera_nc,

Some things were broken about a year ago. MCV fixed that. But I don’t believe they have done anything in terms of adding features. So, give the following a try ([tt]Apps[/tt] > [tt]Develop Apps[/tt] > [tt]Test Luup code[/tt] (Lua)). Replace 999 with the NodeId of your Trane (this is the [tt]ID[/tt] from the [tt]Settings[/tt] tab, not the [tt]Device #[/tt]).

E-Heat:

luup.call_action('urn:micasaverde-com:serviceId:ZWaveNetwork1','SendData',{Node='999', Data='0x40 1 4'},1)

Auto:

luup.call_action('urn:micasaverde-com:serviceId:ZWaveNetwork1','SendData',{Node='999', Data='0x40 1 3'},1)

If that works, you could stick it in two scenes, perhaps triggered by the state of a virtual switch ‘E-Heat’.

Keep in mind that this is write-only.

9

Thanks for the information. I have a scene that triggers based on outside temperature to turn on the dog’s heated water bowl and bed outside so I can add this code to that scene if it works.

Sent from my SPH-D710 using Tapatalk 2

10

@Oti, thanks for the code. I tested it tonight and it did change the mode to EHEAT as expected. But I do want to put out a word of warning to others who may want to try this.

It just so happened that my unit was Heating at the time on the compressor when the command was sent. In this case, the gas pack appeared to fire BUT the compressor continued to operate.

Even when I set the thermostat below ambient temp to kick off heating and within 10 seconds, went back above ambient, the compressor kicked on again.

I had to wait for the compressor delay to expire before attempting to heat again, so it appears that a delay equal to the compressor restart delay programmed in the thermostat needs to be incorporated into the Scene to set EHEAT mode. In other words, the scene would perform a Mode OFF followed by a delay and then the EHEAT mode setting.

I plan to test this on the weekend and will post an update.

11

I believe the EHEAT is designed to be used when your outside unit ALREADY has a low temp cutoff.
Normally with a heat pump (depending on # of stages … I will assume 2)
You have setpoint - 1 1st stage heat (Heat Pump Only)
setpoint - 3 2nd stage heat (Heat Pump Only)
setpoint - 5 AuxHeat (Heat Pump and Aux Electric Heat)

I am guessing at the delta degrees for the different stages … it’s probably programmable.

But if it’s cold outside and the heat pump does not come on you have a 5 degree offset before it kicks the Aux (Electric Heat) on.
So EHEAT will cause the AuxHeat to come on when Stage1 calls for heat. But it will still try to engage the heat pump.

I could be wrong … it’s been over 30 years since I did any HVAC service work.

12

According to the documentation with this particular thermostat, EHEAT mode is used when there is a problem with the Outside compressor and you want to only use AUX heat and lockout the compressor. It allows you to still heat the home until a repair person can come out without causing additional damage to the compressor (although I guess you could also go outside and remove the cutoff switch which is code).

13

I managed to put the delay in and it appears to work perfectly. I will say that the delay must be greater than minimum-on time programmed in the thermostat. I tested it on my thermostat by having it heat on Heat Pump and then issuing the sequence.

When the thermostat went into the Off Mode, it was still showing ‘Heating’ on the Thermostat (which I am sure is due to the minimum on-time programmed for 3 minutes. Once that minimum time completed, the thermostat turned off heating.

Then my delay on the Vera expired and it sent the lua code to go to EHEAT mode and the thermostat turned back on to complete bringing the ambient temp to the original set point and only the Gas Pack was operating.