Yes, quite simple. One existing wire will not be used with the Honeywell because there will only be one fan speed. The RV thermostat had 2 fan speeds. There is little difference in the speeds so not necessary to have 2. Watch the attached video and you should have no problems. Worlds of difference with a good digital thermostat that actually responds to your settings.
https://www.bing.com/videos/search?q...3&&FORM=VRDGAR
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