Mike519

On 9/8/2020 at 1:16 PM, Rick James Bish said:

Old topic I know but here is a diagram I made for using the Nest Learning Thermostat in a 12vdc source RV. Requires a 24vac transformer here  https://www.amazon.com/dp/B07C3J6PQX?ref=ppx_pop_mob_ap_share  and relay board here https://www.amazon.com/dp/B07DYLKH74?ref=ppx_pop_mob_ap_share .  The cost of the transformer and relay board together is less than $40 and this setup controls AC with two fan speeds and heat.

 

 

 

This relay board is a great product, but the max current recommended is 10 amps, which is too low from a safety point.  In rush current from a compressor could be 2x that amount and the relays should be over rated to keep from pitting the contacts, and creating resistance on the contact connections.