Dometic MCS15 - Manual (Page 24)

EN
Troubleshooting MCS5, MCS15
24
No cooling or heating
(contn’d). Fan coil is iced (in cooling). See below.
Fan is not running. See corresponding section in
“Control Panel Troubleshooting”
on page 27.
Seawater plumbing is air-locked. Ensure that seawater plumbing is
installed per the guidelines in the
Installation Manual.
The Marine Climate System is
programmed for Cool or Heat
only, or mechanical control ther-
mostat is rotated too far towards
either Cooler or Warmer setting. Set P1 to the desired value or
rotate the mechanical control
thermostat.
High pressure switch open (in
cooling) due to improper sea-
water flow.
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.
High pressure switch open (in
heating) due to improper airflow. 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).
High-pressure switch is open in
heating mode. System may cycle on high-pres-
sure if seawater temperature is
above 55 °F (12.8 °C).
Compressor’s thermal overload is
open due to either of the above
reasons. Compressor needs to cool down.
Turn system off for a while (it may
take up to three hours to reset
thermal overload).
No cooling Control panel may not be in “cool”
position. Reset control panel.
Coil iced. See below.
No heating. Unit is “cool only”, or if reverse
cycle, reversing valve may be
stuck. Tap reversing valve lightly with
rubber mallet while unit is in heat
mode.
Call for service if that does not
correct the problem.
Problem Possible Reason Solution