Got Armstrong AC running but I need thermostat voltage help

[LakeFall]

I replaced the potential relay and capacitor and have the unit up and running after sitting for 20 years but the thermostat is missing. (I jumpered the wires together instead) Is the 24V AC or DC voltage? The trailer is 300 miles away and of course I assumed that the schematic had that info, any help would be greatly appreciated!

[rmkrum]

Looking at the schematic, it’s 24 volts AC from that transformer. A Standard thermostat will work fine.

[LakeFall]

Originally Posted by rmkrum

Looking at the schematic, it’s 24 volts AC from that transformer. A Standard thermostat will work fine.

So if a transformer secondary voltage isnt specified then it is the same voltage type as the primary voltage?

[TomW]

Transformers only output AC voltage. Diodes are required to convert that to DC and your schematic does not show any diodes. 24 volts AC is pretty much standard in the HVAC world.

Tom

[cbburke]

The original thermostat is a standard mechanical unit. It generates no voltage.
Emerson 1C26-101 Mechanical Heat/Cool Thermostat will do. $10 on Amazon

[TomW]

I replaced my original mechanical thermostat with a battery-powered digital version primarily because the digital model is immune to a door being slammed and controls better in general.

Tom