Greetings to all, I'm hooking up a line voltage thermostat, cool only in my camper. My ? Is, does it make a difference which way you would hook the wires up? One is red and one is black , this is just a switch I would not think it makes a difference
For a single pole switch (just two wires) it does not make any difference.
You have to be careful with a 2 pole switch (4 wires), intended for 240 volt circuits. If you make a mistake you could short out and burn out the switch (connect both hot supply wires to the two wires going to one switch pole). Except for this, it also does not make any difference.
Check the switch instructions.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.
if it is for a 115V unit break the hot/black at the stat so you read 115V to ground but not out the other side of that black to the unit to ground.....if 230V either won't matter just realize one side of the unit is hot in the off position at all times