Just wondering if you have an idea if wiring my zwave tstat to a 12v relay and a Honeywell 5816 on loop one. The idea is to beable to have my swamp cooler which is plugged into a zwave 120v outlet be controlled by my zwave tstat in my cool schedule through alarm.com I am having difficulty wiring this as I am not that familiar with the cooling outputs on a thermostat. If I put my volt meter across rc and y and switch to cool and lower the temp nothing changes so I figure I have the terminals wrong. Thank you very much
The idea is to beable to have my swamp cooler which is plugged into a zwave 120v outlet be controlled by my zwave tstat
It looks like this is related to this question.
The suggestion previously was to use an additional non-Z-wave Tstat for this. An existing Z-wave thermostat would be switching 24VAC if connected to an HVAC, not 12VDC.
Could you clarify what model of thermostat you are trying to use and whether or not it is currently wired to an HVAC system?
If I put my volt meter across rc and y and switch to cool and lower the temp nothing changes so I figure I have the terminals wrong
If your Tstat is wired to an HVAC and all is wired properly, it is switching the hot output. Long story short, if checking with a volt-meter between Rc and Y you are essentially applying both leads to the same circuit wire. You would need to check between Y and C (if C is connected to HVAC).
If you do not have the Tstat connected to an HVAC, you could simply use any cheap Tstat and deliver a supplementary power supply hot wire to Rh/Rc, then connect Y to the Positive Trigger input on the relay. The negative wire from the power supply would be wired directly to the Negative trigger input on the relay. Note you should not do this with a thermostat connected to an HVAC!
To help visualize I have attached an example diagram. When a call for cool is made, positive power into Rc (jumped from Rh) is passed out through Y.
If you have a Z-wave Tstat you are not using otherwise, it could be used for this purpose. Non-Z-wave was suggested for price and battery life.
Hi Jason thank you for your response.
My zwave tstat is not connected to any cooling system; only a furnace.
I really want to beable to use alarm.coms cooling schedule as this would make it easier to manage.
So all I need to do is wire it the way you have in the diagram or do I NEED a separate tstat not connected to my furnace?
Hmm, well, I do not recommend trying to connect the relay to any Tstat currently connected to an HVAC. It is probably possible to remove the jumper between Rh and Rc and feed them separately, or use a 24VAC relay and the existing HVAC power, but there are potential hazards and HVAC repair is extremely expensive compared to a new or used Tstat.
It would be better to get a separate Z-wave Tstat.
I will try to separate the rc/r before using a separate zwave tstat; I have one but I’d rather have only one.
So I got it working.
I wired a 5816 on loop 1 across terminals rc and yellow. I programed the 5816 as a non monitored contact and have rules in alarm.com to turn on my thermostat when the zone closes eliminating the need to use a relay. I pulled the jumper between rc and r so I can use both heating and cooling on the same zwave tstat (it’s still cold in the mornings here)
Thanks for your help.
Keep in mind when set up that way with one Tstat it would engage the fan (g) as well on a call for cool. I’m not sure if this might make an evaporative cooler less efficient, but something to consider.