Marine Air Systems vector compact - MCP Mechanical Control Panel Troubleshooting Guidelines

PASSPORT II DIGITAL CONTROL TROUBLESHOOTING GUIDELINES
CONT.
FAULT
"HHH" is
displayed on
Passport II.
"PPP" is
displayed on
Passport II.
System runs
continuously.
UAAA" is
displayed.
POSSIBLE REASON
High-pressure switch is open
(in cooling) due to improper
seawater flow.
Low-pressure switch is open
due to low seawater and/or low
return air temperatures.
Low pressure switch is open
due to loss of refrigerant.
Improper Passport II air sensor
location.
Indicates failed face plate air
sensor, alternate air sensor or
display cable
CORRECTION
Strainer or intake may be plugged, seacock may
be closed, check seawater hose for kinks or
collapses. Verify pump operation; check pump
circuit breaker if applicable.
Try restarting the a/c unit, the optional low
pressure switch has a ten minute time delay that
may be in effect.
Check a/c unit for refrigerant oil leakage, call
service technician (see back of manual).
Verify display head location with criteria found
in this manual. Install alternate air sensor if
necessary.
Unplug alternate air sensor if installed or plug in
alternate air sensor if not installed. Try another
display cable.
MCP MECHANICAL CONTROL PANEL TROUBLESHOOTING GUIDELINES
FAULT
Fan is not
running.
No cooling or
heating.
System runs
continuously.
POSSIBLE REASON
MCP system switch is not set
properly
MCP fose blown.
High-pressure switch is open
(in cooling) due to improper
seawater flow.
High pressure switch open (in
heating) due to improper air
flow.
Compressor's thermal overload
is open due to either of the
above two reasons.
Improper MCP air sensor
location.
CORRECTION
Set MCP system switch to "START" for fan
only or "RUN" for cooling and heating.
Replace 10 amp fuse behind MCP panel.
Strainer or intake may be plugged, seacock may
be closed, check seawater hose for kinks or
collapses. Verify pump operation. Check pump
circuit breaker if applicable.
Remove any obstructions in return air stream.
Clean return air filter and grille. Check for
crushed or restricted ducting, ducting must be as
straight, smooth and taut as possible.
Compressor needs to cool down. Turn system
off for a while (it may take up to three hours to
reset thermal overload).
Verify return air sensing bulb location with
criteria found in this manual.
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