Line volt t stat for switch loop

[electrofelon]

I have a 240v heater with power to the heater and a 2 wire switch loop to the thermostat. Is there a digital/programmable t stat that will work with this setup? I'm looking at this one:

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But I'm a bit confused. They have one that says DP (not the link) and one that says SP (the linked one). But the SP appears to still have 4 wires. I thought it was probably just the wrong photo, but I looked at the manual and it appears to still use 4 wires. I assume it still needs 240 volts to run the electronics and can't be used for a 2 wire switch loop. Is this correct? Anyone know of one that will work? I know the regular mechanical ones will work but I'm ssuming client wants something higher end.

 

[LarryFine]

It could be that the DP opens both poles during operation, and the SP opens only one.

With two wires in your loop, you'd only use two wires anyway; make sure you use the correct two.

 

[electrofelon]

It could be that the DP opens both poles during operation, and the SP opens only one.

With two wires in your loop, you'd only use two wires anyway; make sure you use the correct two.

Perhaps the stat needs both poles to power itself? Seems odd they would make a SP and DP version if the SP still needs 4 wires (or 3).

 

[synchro]

This one appears that it should work in a 2-wire switch loop based on the user manual. It won't work if the heater has a fan in it..

https://www.stelpro.com/en-US/4000-w-ki-thermostat-smart-home-z-wave

http://pro.stelpro.com/contenu/us/pdf/guides/User/STZW402.pdf

Stelpro KI Z-Wave 7-Day Programmable Wall Thermostat for Electric Baseboard and Convectors in White STZW402WB+ - The Home Depot

The Stelpro KI thermostat for the smart home is the first ever Z-Wave line voltage thermostat in North America. KI thermostats can easily be integrated into the Z-Wave network of your home, allowing you

www.homedepot.com

Stelpro KI Review: Finally, A Line Voltage Smart Thermostat

The Stelpro KI STZW402+ is a smart thermostat for line or high voltage electric heaters. It connects to your smart home via Z-Wave or ZigBee wireless.

thesmartcave.com

 

[synchro]

This one works with heaters that have fans:

https://www.sinopetech.com/wp-content/uploads/2020/01/TH1123ZB-TH1124ZB-Thermostat-electric-heating-Zigbee-Installation-Guide-Sinope-G.pdf

Sinopé Smart Thermostat for Electric Heating TH1124ZB (Compatible with Alexa) 4000 W / 240 V - - Amazon.com

Sinopé Smart Thermostat for Electric Heating TH1124ZB (Compatible with Alexa) 4000 W / 240 V - - Amazon.com

www.amazon.com

 

[electrofelon]

This one works with heaters that have fans:

https://www.sinopetech.com/wp-content/uploads/2020/01/TH1123ZB-TH1124ZB-Thermostat-electric-heating-Zigbee-Installation-Guide-Sinope-G.pdf

Sinopé Smart Thermostat for Electric Heating TH1124ZB (Compatible with Alexa) 4000 W / 240 V - - Amazon.com

Sinopé Smart Thermostat for Electric Heating TH1124ZB (Compatible with Alexa) 4000 W / 240 V - - Amazon.com

www.amazon.com

Thanks. This heater does have a fan.

It appears this is a two wire programmable line voltage. Doesn't appear to need batteries either.

Honeywell RLV4305A1000/E 5-2 Day Programmable TRIAC Line Volt Thermostat