Lochinvar 495, 065 Hot Surface Ignition System, Hot Surface Igniter and Ignition Control Module

Installation and Service Manual

Remote Mounting of Sensor

You must mount the outside air temperature sensor outside the building. To mount remote sensors, follow the guidelines below. Take care to correctly wire sensors to the unit. Erratic temperature readings can be caused by poor wiring practices. Twist the wires between the unit and the remote sensor. Turn wires at least three or four turns per linear foot of wiring. This provides common mode rejection of some types of electrical interferences.

1.Do not route temperature sensor wiring with building power wiring.

2.Do not locate temperature sensor wiring next to control contactors.

3.Do not locate temperature sensor wiring near electric motors.

4.Do not locate temperature sensor wiring near welding equipment.

5.Make sure good mechanical connections are made to the sensor, any interconnecting wiring and the controller.

6.Do not mount sensor with leadwire end pointing up in an area where condensation can occur.

7.Use shielded wiring to connect the sensor to the control when the possibility of an electrically noisy environment exists. Shielded cable is recommended on all cable runs of more than 25 feet in length.

Note: Ground the cable shield at the connection to the boiler temperature control only. Do not ground the shielded cable at the sensor end.

To maintain temperature accuracy, sensor wires should be at least 18 AWG, see Table N below.

TABLE - N

Remote Wire Connection

Wire	Maximum
Gauge	Allowable Length
12 GA	100 ft
14 GA	75 ft
16 GA	50 ft
18 GA	30 ft

HOT SURFACE IGNITION SYSTEM

Hot Surface Igniter and Ignition Control Module

This unit has one ignition module and one hot surface igniter.

Figure 38 - Hot Surface Igniter

￿Caution: The igniter is extremely fragile, be very careful when removing. A faulty or damaged hot surface igniter MUST BE replaced with a Lochinvar PLT3400 igniter. Do not use general purpose field replacement igniters.

	F2
FC-	FC+
	F1
	P3
	+
	DS2

Figure 39 - Hot Surface Ignition Control Module

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