Troubleshooting - Mitsubishi Electric ecodan Homeowner Quick Start Manual

Troubleshooting

The following is to be used as a guide to possible problems. It is not exhaustive and all
serious problems should be investigated by the installer or another competent person.
Users should not attempt to repair the system themselves. At no time should the system
be operating with the safety devices by-passed or blocked up.
Cold water at taps
Hot water may be scheduled off:
Please check schedule settings and
alter if necessary.
All the hot water from tank may be used:
Ensure DHW mode is operating and wait
for tank to re-heat.
Heat pump or electric heaters not working:
Contact installer.
Water discharges from one
of the relief valves
The system has overheated/over pressurised:
Please switch off power to the heat
pump and any immersion heaters then
contact installer.
Small amounts of water drip
from one of the relief valves
Dirt may be preventing a tight seal in the valve:
Please twist the valve cap in the direction
indicated until a click is heard. This will release
a small amount of water flushing dirt from the
valve. Be very careful, the water released will
be hot. Should the valve continue to drip,
contact installer as the rubber seal may be
damaged and need replacing.
Noisy pipework
Air may be trapped in the system:
Try bleeding radiators (if present) using
a radiator key, if the symptoms persist
contact installer.
Heating system does not get
up to set temperature
Prohibit, schedule or holiday mode selected:
Check settings and change as appropriate.
Incorrectly sized radiators:
Contact installer.
The room in which the temperature sensor
is located is at a different temperature to
the rest of the house: Reposition the
temperature sensor to a more suitable room.
An error code appears in the
main controller display
The indoor or outdoor unit is
reporting an abnormal condition:
Make a note of the error
code number and contact installer.
Pump runs without reason
for short time
Pump jam prevention mechanism to inhibit
the build up of scale is working. Normal
operation, no action necessary.
Mechanical noise heard coming
from cylinder unit
Heaters switching on/off:
Normal operation, no action required.
3-way valve changing position between
DHW and heating mode:
Normal operation, no action necessary.
Heating emitter is hot in the DHW
mode (the room temperature rises)
The 3-way valve may have foreign objects in
it, or hot water may flow to the heating side
due to malfunctions: Contact installer.
'Smoke' is blown from the front
of the Ecodan in cold weather
This is warm air being blown from the
Ecodan to ensure the internal parts don't
freeze. It is known as the defrost cycle:
Normal operation, no action necessary.
Power failure
All settings will be saved for 1 week with
no power, after 1 week Date/Time ONLY
will be saved.
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