Scope
This document provides step-by-step instructions for startup of new HC heaters and HCS heaters. HC heaters have a manifold and auxiliary (side) pumps that distribute thermal fluid to multiple circuits that are independently controlled (Fig. 1). HCS heaters do not have a manifold, but have a single circuit that circulates fluid through the heater, tanks and other equipment being heated (Fig. 3).

Figure 1. Heatec HC heater with side pumps.

Intended users
Instructions in this document are intended for use by qualified asphalt plant operators and maintenance personnel. Qualified persons are those who understand electrical shock hazards and how to avoid them. Such persons are also familiar with the burn hazards of working with liquid asphalt and thermal fluids heated to temperatures in excess of 300 degrees F.

Some procedures require setting and testing parts inside the heater electrical control panel while it is open and electrical power is turned on. This should be done only by qualified persons using electrical testers to make sure wires and terminals they may accidentally touch are deenergized so that no electrical power is present.

Prior to startup
The following conditions are required prior to startup:

• The incoming gas supply line pressure is 1 psig max.
• You have a propane bottle to use for the gas pilot on combination gas-oil burners if gas is shut off. Gas pressure of the bottle should not exceed 10 psi.
• The heater is properly installed, piped, and wired.
• The equipment that is to be heated by thermal fluid is fully piped and leak-tested.
• There is no thermal fluid in the heater or in its piping circuits.

Preliminary procedure:

1. Make sure the power disconnect switch (the handle) on the control panel (Fig. 2) is set to OFF.
2. Make sure the switches marked HEATER CONTROL and CIRC. PUMP are set to OFF.
3. For HC heaters, make sure all switches marked AUX. PUMP are set to OFF.
4. If heater operates on gas only, remove fuel pump coupling. Please refer to separate Tec-Note on Servicing for procedure for removing the coupling.
5. Make sure the two shutoff valves for high and low media pressure switch are open (Fig. 4).
6. Make sure the two shutoff valves on the sight gauge (Fig. 5) are open.
7. Install drain valve (Fig. 6) (not supplied) in the plug port of the strainer (M, Fig. 3). Be sure to coat threads with a high temperature pipe thread sealant such as Rectorseal No. 5. Improperly sealed threads will result in leakage of thermal fluid.
8. Set the switch labeled HEATER ALARM to OFF while you are working near the heater. This setting turns off the alarm horn (which is extremely loud), but does not turn off the light labeled HEATER ALARM.
9. Open the control panel and turn on all breakers except main disconnect breaker. There are four toggle breakers and two rotary breakers. HC heaters have an additional rotary breaker for each auxiliary pump.