Section 5 - Troubleshooting; Safety Requirements; Using An Ohmmeter; Setting Up The Ohmmeter - Desa B350D Service Manual

H I G H P R E S S U R E P O R T A B L E F O R C E D A I R H E A T E R S E R V I C E M A N U A L
TROUBLESHOOTING
S E C T I O N
5

Safety Requirements

This service manual is intended for
use by persons with adequate electri-
cal and mechanical skills. Only attempt
to repair heater if you have these skills.
Personal injury and property damage
can occur to those who attempt to
repair heater without these skills.
• Unplug heater and let cool before
servicing. Note: Certain test require
you to connect heater to electrical
outlet. If so, only connect heater for
time needed to complete test.
• Do not bypass any safety devices.
• If replacement parts are needed, only
use factory authorized replacement
parts. Do not substitute with non-
factory parts.
• Make sure all electrical connections
are secure and all harness leads are
in place before connecting heater to
electrical outlet.

Using an Ohmmeter

Throughout the diagnostic procedures, we
require you to check continuity of the electri-
cal circuits. You will do this using an ohmme-
ter. To set up the ohmmeter for these test,
follow the instructions below.

Setting Up the Ohmmeter

1. There is a small plastic screw in the
center of the ohmmeter, just under the
meter needle. Turning this screw will
move the needle. Turn the screw to ad-
just the meter needle to the zero "0" mark
on the far left of the scale (see Figure 11).
2. Make sure batteries are in ohmmeter.
Set ohmmeter on the RX1 position.
3. Plug test leads into ohmmeter. If test
leads do not have alligator clips, install
alligator clips to leads.
12
!
WARNING
WARNING ICON G 001
!
WARNING
WARNING ICON G 001
!
CAUTION
WARNING ICON G 001
15
CAUTION: OBSERVE SAFETY RULES
OFF
1000 1000
300 300
100 100
30 30
10 10
3 3
1
x1
x10
.1
x100
10 V-
x1K
100
x10K
1000 T
E
S
COM-
T
Figure 11 - Ohmmeter Adjusted to "O" Mark

Calibrating the Ohmmeter

1. Connect the alligator clips to each other
(see Figure 12). The meter needle should
move to the far right of the ohms scale (Ω).
15
CAUTION: OBSERVE SAFETY RULES
OFF
1000 1000
300 300
100 100
30 30
10 10
3 3
1
x1
x10
.1
x100
10
x1K
100
x10K
1000 T
E
S
COM-
T
Figure 12 - Ohmmeter with
Alligator Clips Connected
2. Use the OHM thumb adjustment knob to
adjust the meter needle to the zero "0"
mark on the far right of the ohm scale (Ω).
Note: If you are using a digital ohmmeter,
calibrate according to manufacturer's instruc-
tions.

Diagnostic Information

The following pages contain various diag-
nostic information. To use the information,
determine what problem conditions exist and
follow the test procedures listed for that prob-
lem.
MA
V- MA