ASPT Service Manual

Table Of Contents
SERVICING
91

Heating Output = KW x 3413 x Corr. Factor
Actual CFM = CFM (from table) x Corr. Factor
BTUH = KW x 3413
BTUH = CFM x 1.08 x Temperature Rise (T)
CFM = KW x 3413
1.08 x T
T = BTUH
CFM x 1.08

Each individual heater element is protected with a limit
control device connected in series with each element to
prevent overheating of components in case of low airow.
This limit control will open its circuit at approximately 150°F.
WARNING






1. Remove the wiring from the control terminals.
2. Using an ohmmeter, test for continuity across the normally
closed contacts. No reading indicates the control is open
- replace if necessary.
If Found Open - Replace - Do Not Wire Around.


Each individual heater element is protected with a one time
fuse link which is connected in series with the element.
The fuse link will open at approximately 333°.
WARNING

1. Remove heater element assembly so as to expose fuse
link.
2. Using an ohmmeter, test across the fuse link for continuity
- no reading indicates the link is open. Replace as
necessary.

333°F. DO NOT WIRE AROUND - determine reason for
failure.

WARNING

1. Disassemble and remove the heating element.
2. Visually inspect the heater assembly for any breaks in the
wire or broken insulators.
3. Using an ohmmeter, test the element for continuity - no
reading indicates the element is open. Replace as
necessary.
Refrigeration Repair Practice
DANGER



When repairing the refrigeration system:
WARNING






1. Never open a system that is under vacuum. Air and
moisture will be drawn in.
2. Plug or cap all openings.
3. Remove all burrs and clean the brazing surfaces of the
tubing with sand cloth or paper. Brazing materials do not
ow well on oxidized or oily surfaces.
4. Clean the inside of all new tubing to remove oils and pipe
chips.
5. When brazing, sweep the tubing with dry nitrogen to
prevent the formation of oxides on the inside surfaces.
6. Complete any repair by replacing the liquid line drier in the
system, evacuate and charge.