BASO Pilot Burners User Manual

Application Note
Issue Date September 8, 2008

Pilot Burners/Thermocouples

Application

Good Practice
Rules

This document is intended to aid the appliance engineer or authorized
service contractor in making a standing pilot application. Pilot burners are
manufactured with a variety of tips and mounting configurations.
Representative types of mounting with standard pilots are illustrated in
Figure 1. Dimensions shown are approximate and may vary, provided the
requirements of good ignition are met. See Good Practice Rules.

The following are good practice rules for governing the location of the
pilot:

• Locate the pilot so that it can be reached easily for lighting.

• Locate the pilot in a position that has a fixed relation to the main

burner (see Figure 1).

Mounting Position Examples for Pilot Burners

Pilot I g ni tion Port 3 / 8 " Above
and 1/4" A way (Or C l o s er )
from Center of Nearest Main
Burner Port

pilot

Figure 1: Pilot Location

• Locate the pilot burner in a position that will receive incoming air and
not products of combustion from the main burner. The pilot should
be located where it will not be affected by an excessive draft of
incoming air.

• Locate the pilot burner in such a position that it does not receive the
full force of igniting or extinguishing puffs from the main burner.

• Locate the pilot burner in a position that will allow ready removal for
cleaning.

© 2008 BASO Gas Products 1
Part No. BASO-AN-PB/THERMOCOUPLES, Rev.- www.baso.com

After
Installation

When the pilot burner has been installed, carefully make the following
observations and tests:

1. Ensure the main burner flames do not impinge on any part of the pilot
burner.

2. Ensure the pilot burner will ignite the main burner under all pilot
burner conditions that maintain the safety shutoff device (BASO®) in
the On position. (See the Safety Turn Down Test section.)

3. Ensure the pilot burner will not be smothered out or snuffed out:

• when the main burner is ignited from a cold start.

• when the main burner is ignited with the appliance at the

maximum temperature conditions of operation.

• with normal variation in air adjustments of the main burner.

• with rapid Off and On operation of the main burner with the

combustion chamber cold.

• with rapid Off and On operation of the main burner with the
combustion chamber hot.

• with continued operation of the main burner.

Thermocouple
Output Test

Instructions for
Testing BASO
Pilot Burners with
K15, K16, K19, 80,
85, 87, and 88
Thermocouples

4. To ensure proper operation, the pilot flame must produce a
satisfactory millivoltage as described in the Thermocouple Output
Test section.

Note: When a pilot is to be applied to an appliance already in the field,

obtain the appliance manufacturer’s recommendations for the
correct pilot specification and location dimensions for the
particular model appliance.

When the pilot is applied properly, the thermocouple will produce an open
circuit millivoltage as shown in Table 1. Normal operating voltages, as
shown, must be obtained to give trouble-free performance. Perform the
following tests with the Y99AB Test Kit.

Attach the proper junction terminal of the millivoltmeter to the
thermocouple lead and measure the open circuit voltage. Allow at least
five minutes for each meter reading. For specifications, see Table 1.

2 Pilot Burners/Thermocouples Technical Bulletin