User Instructions
Page 11
Weather Compensation
Your Grant Aerona³ heat pump has a built-in ‘weather compensation’
function that varies the heating system water temperature as the outdoor air
temperature changes, i.e. as the outdoor air temperature falls the system fl ow
temperature increases and vice versa . Refer to Section 3.7 of the Installation
Instructions supplied with the heat pump.
This function helps to improve the thermal effi ciency of your heating system.
The heat pump is supplied with default settings for this weather compensation
functions and these should be checked and altered, if required, by the installer
during commissioning to suit your heating system.
When the actual outside air temperature is the above the ‘maximum outdoor
air temperature’ setting of the weather compensation function the heat pump
will NOT operate for heating, even if there is a demand from the heating
system controls.
This is not a fault with the heat pump but the normal operation of the Weather
Compensation function automatically preventing operation of the heat pump
(and heating system) when the outside air temperature indicates that use of
your heating system would be unnecessary and wasteful.
Frost Protection
Your Grant Aerona³ heat pump is fi tted with automatic frost protection that
will operate when either the outside air temperature or the system water
temperature falls to a pre-set value (factory default setting 4°C). For further
details refer to Section 8.3 of the Installation Instructions supplied with the heat
pump.
This frost protection function will operate even when the heat pump is switched
OFF at the remote controller. See the ‘To Switch the Heat Pump ON and OFF’
section of these User Instructions.
As the heat pump frost protection involves the operation of the circulating
pump, it is perfectly normal to hear the circulating pump running (when the
heat pump is off) during periods of cold weather.
The circulating pump may operate for long periods, e.g. all night, when the
conditions dictate but as this pump has a very low power consumption, the
cost involved in protecting your heat pump is very small.
Looking after your Heat Pump
Grant Aerona³ Heat Pumps require very little maintenance but it is important
that the air inlet grille (at the rear and left hand side of the unit) is kept clear at
all times.
Remove any build-up of leaves, snow or any other debris from the air inlet
grille.
Also, ensure that the fan outlet is not obstructed at all times.
To ensure that it continues to operate effi ciently your Grant Aerona³ heat
pump should be serviced annually, as detailed in Section 10 of the Installation
Instructions supplied with the unit. Contact your installer or service engineer to
carry out this work.
Troubleshooting
If your heat pump fails to operate:
First
check:
Is the power supply is switched ON at the external isolator?
If YES:
Check that the heat pump is switched ON at the display pad (if fi tted).
Refer to the ‘Heat Pump remote Controller’ section of these User
Instructions.
If YES:
Check if there is a demand from the heating system controls.
Refer to the ‘Heating System Controls’ section of these User Instructions.
If YES:
Check if the outside air temperature is greater than the ‘maximum outside
air temperature’ setting of the Weather Compensation function, as this
would prevent the heat pump from operating to meet a heating demand.
Refer to the ‘Weather Compensation’ section of these User Instructions.
If YES:
Check the display on the remote controller. Is an error code displayed?
If YES:
What is the error code?
Refer to Section 11 of the Installation Instructions supplied with the heat
pump for a full list of the error codes.
Contact your installer or service engineer for assistance.
Radiator temperatures
Your Grant heat pump is designed to work at lower operating temperatures
than traditional oil or gas fi red boilers. Radiators will therefore feel cooler to
the touch, but this should not cause a problem with the heating of your house.
The system will have been designed to work at these lower temperatures and
the heat pump will be set to ensure the correct comfort levels are maintained.
Underfl oor heating systems will require a longer pre-heat period to bring the
fl oor up to operating temperature.
The heat pump has been designed to be as effi cient as possible and will
operate at a ‘set point’ temperature depending on conditions inside and
outside of your house. Due to this, your radiators will be warmer some days
and cooler others. This is normal and the heat pump is working correctly.
NOTE
This does not apply to the hot water heating
function of the heat pump. This will still operate
even if the outside air temperature is greater
than the maximum outdoor air temperature
setting of the Weather Compensation function.
NOTE
If the electrical supply to the heat pump is
switched off, e.g. at the external isolator, the
frost protection function will NOT operate.
CAUTION
Do not either:
Stack anything (e.g. garden furniture, bicycles,
etc.) either on or against your heat pump.
Do not place any cover over the unit.