Figure 35. LOW LEVEL CONTROL MOUNTING.
The low level control has a 21/2" pipe thread and is mounted into a 21/2" pipe coupling welded into
the expansion tank. In mounting the control to the tank, the hex nut should be turned so that the
1/2 " conduit opening is at the top in a horizontal plane. The float must move up and down in a
The dual switches are activated by movement of the float ball. When the ball rises, the top switch is
closed; when the ball falls the switch opens. This is controlled by the heat transfer oil level. The second
switch is not used. It is left disconnected.
The switch designations are 1 & 2 and 3 & 4. On a rising level, 1 & 2 close with 3 & 4 opening.
SWITCH RATING: 115V.A.C. .......- 7.4 Amps.
230 V.A.C. -.......- 3.7 Amps.