I looked on this page and found the following diagram.
White rodgers fan center wiring diagram.
White rodgers division emerson electric co.
Wiring diagram for the white rodgers fan limit control used at line voltage.
Ok i read a little on the fan limit control concept.
Wiring diagram for the white rodgers fan limit control used with low voltage equipment.
Thru fan control center.
Do not use on circuits exceeding specified voltage.
Features an energy limiting class ii transformer design and color coded pre stripped leads.
9797 reavis road st.
The explanation is for a honeywell fan limit control but it seems similar enough to the white rodgers device i an using.
Thermostat wiring details connections for the white rodgers brand of room thermostats.
White rodgers 90 113 single pole double throw spdt fan control center is a transformer and relay combination for easy installation on a 4 x 4 junction box.
Fan control centers printed in u s a.
The original heater diagram shows one side black v but i can t figure where black from relay goes where the black for transformer goes 3 wires in that.
The limit is a high temperature safety limit i guess.
This article gives a table showing the proper wire connections nearly all types of white rodgers room thermostats new and old used to control heating or air conditioning equipment including the white rodgers f90 2 wire and 3 wire thermostat installations.
All wiring must conform to local and national electrical codes and ordinances.
Louis missouri 63123 5398 part no.
37 5786a 9716 this control must be installed by a qualified installer.
Transformer and relay combination for easy installation on a 4 x 4 junction box.
Click to enlarge any image adapted from the white rodgers 5d51 installation instructions cited here.