TEST PROCEDURES - STEWART-WARNER AND HUPP HEATERS- Contlnued
THINGS TO CHECK
13 Check Hi/LO operation as follows:
a. Note temperature reading in outlet duct.
b. Set control box for HI heater operation.
c. Note new reading after a few minutes.
Ail models-Reading should nearly double.
Stewart-Warner heaters-Fuel control valve adjustment,
Hupp heaters -Fuel regulator valve adjustment, Hi/LO pressure regulator, Hi/LO fire relay
Step 14 is a test of the overheat switch. Perform this test only if the overheat switch
was replaced or is believed to be defective.
Do not perform step 14 if running the heater on gasoline.
Always have a fire extinguisher handy when performing step 14.
Never perform this test alone; have someone with you.
14. Check operation of overheat switch as follows:
a. Set control box for HI heater operation.
b. Connect test continuity to overheat switch.
On Stewart-Warner heaters, connect to overheat switch terminal 30.
On Hupp heaters, connect to terminal 7 of terminal strip.
c. Block off about 70 percent of the ventilation air inlet exhaust doughnut insert (item 1, appendix E).