How I saved $60 on my Heating/Electric Bill

Other Devices & Integrations Climate Control & Temperature Sensors
#1

I thought that this would be something others would find useful.

I have a new construction house (2516 Sq Ft), and it has a gas furnace with A/C. The thermostat that came installed was a Honeywell VisionPro TH8000 series unit. Since I wanted a ZWave version, I did some research and found that the Honeywell YTH8320ZW1007 Thermostat was basically a drop in replacement (well almost, I had to hookup an extra wire for this to work, and luckily the installer ran a cable with plenty of wires in it for future expansion).

I found the ZWave version of my thermostat from a wholesale distributor on Ebay for $79 (it was a brand new unit that had been “used” and didn’t have the mounting screws which I already had).

What I am doing is having my Vera put the thermostat in EnergySavings mode when my alarm system is armed in Away mode, and reset it back to normal mode when I return (the alarm is disarmed).

To set to EnergySavings mode, I do the following::

-Create a new scene (I call my Thermostat Away Mode)
-Set a schedule to run every 2 minutes
-Use the following LUUP code in the scene:

[code]local PARTITION_DEV_NUM = 61
local THERMOSTAT_DEV = 93

local state = luup.variable_get(“urn:micasaverde-com:serviceId:AlarmPartition2”, “ArmMode”, PARTITION_DEV_NUM)

local detailed_state = luup.variable_get(“urn:micasaverde-com:serviceId:AlarmPartition2”, “DetailedArmMode”, PARTITION_DEV_NUM)

– SHOW VARIABLES FOR DEBUGGING
luup.log("ThermostatAway- "…state)
luup.log("ThermostatAway- "…detailed_state)

if (state == “Armed”) then
if (detailed_state == “Armed”) then
local status = luup.variable_get( “urn:upnp-org:serviceId:SwitchPower1”, “Status”, THERMOSTAT_DEV) or “0”
if (status == “0”) then
luup.log(“Thermostat already in Energy Saving Mode. Skipping…”)
else
luup.call_action(“urn:wdsc-hvac-org:device:WDSC_HVAC1”, “RestartPolling”,{ delay=0 }, 96)

		luup.log("Alarm armed in Away mode, setting Thermostat to Energy Savings Mode.")
		luup.call_action("urn:upnp-org:serviceId:SwitchPower1","SetTarget",{ newTargetValue="0" }, THERMOSTAT_DEV)
	end
end

end
[/code]

Once the exit delay on the alarm has expired and the system goes into Away mode, this code will catch it within 2 minutes and switch my thermostat to EnergySavings mode (and switch off the WDSC HVAC plugin I am also using).

When I come home and disarm my alarm, I use the following to set the thermostat back to Normal mode:

-Create a new scene (I call my Thermostat Home Mode)
-Set a trigger to fire when the alarm system is disarmed
-Use the following LUUP code to reset the polling interval in the WDSC HVAC plugin. Using the WDSC HVAC plugin ensures that if I disarm the alarm but keep a door open that is on its list of security sensors, that it handles this. Since the thermostat is still on and running in EnergySavings mode (just using higher/lower setpoints for cooling and heating to save energy), this plugin will turn the thermostat into OFF mode so I don’t heat/cool the outside. The plugin also handles changing the thermostat back to normal mode.

[code]luup.call_action(“urn:wdsc-hvac-org:device:WDSC_HVAC1”, “RestartPolling”,{ delay= 300 }, 96)

[/code]

I’ve noticed that my Heating/Electric bill has been dropping since I’ve set this up.

#2

Nice :slight_smile:
I’ve tried something similar with my Vera: shut down heating and A/C when I leave the house, close radiators in certain rooms when no one is there (lights are off), shut off heating in the bedroom during the day, etc. Too early to tell if this saves money; we’ve had weird winters and summers so the utility bill is a poor indication.

#3

You should be able to call your Utility company and ask them for average Degree Day readings for the month. They often track that as it’s an indicator of required demand. You should then be able to normalize your power use. You can probably also find some on the internet for your area.

#4

at a friends house i took the Honeywell T87G1006 of the wall and replaced it with a fibaro duo-switch and let Vera do the heating control with help of 2 tempsensors on 2 doorsensors and put the duo-switch in “off” position when alarm is turned on. saved about 1/3 of the costs he normally has for heating.

#5

For ac you can save even more if you are on Time of Use.

Basically you cool the house 8 degrees lower before peak and let it “coast” during peak. I was able to save more than what my nest did.

#6

[quote=“intveltr, post:2, topic:177034”]Nice :slight_smile:
I’ve tried something similar with my Vera: shut down heating and A/C when I leave the house, close radiators in certain rooms when no one is there (lights are off), shut off heating in the bedroom during the day, etc. Too early to tell if this saves money; we’ve had weird winters and summers so the utility bill is a poor indication.[/quote]

I actually saw quite a bit of savings after the first month of doing this. I was surprised. I haven’t lived in my new house long enough to experience a winter, but I have been through a summer, and we had quite a bit of warmer than normal days.