Installation Instructions 17
059840‐00 Rev. A
Heat‐Timer Corp.
Wiring to a Motorized Valve
NOTE: The EPU‐D does not source power to the motorized valve
terminals. An external 24Vdc power source is required and must be
connected in series, as shown in the diagram.
1. Run the motorized valve signal wiring through a knockout located on
the bottom of the EPU‐D enclosure.
2. Connect the motorized valve Close terminal to terminal 6 on the
EPU‐D.
3. Connect the motorized valve Open terminal to terminal 8 on the
EPU‐D.
4. Connect a 24Vac transformer power source.
a. Run a transformer wire through a knockout located on the bottom
of the EPU‐D enclosure and connect terminal 7 on the EPU‐D to a
transformer 24Vac terminal.
b. Connect the motorized valve Common terminal to a transformer 24Vac terminal.
Wiring to a Boiler
NOTE: The EPU‐D does not source power to the boiler terminals. Wire the burner
output in series with the boiler limit circuit.
1. Run the burner enable signal wires through a knockout located on the bottom of
the EPU‐D enclosure.
2. Connect a burner enable terminals to terminals 7 and 8 on the EPU‐D.