Nibe F1255 Installer Manual page 54

Draining the water heater
The siphon principle is used to empty the hot water
heater. This can be done either via the drain valve on the
incoming cold water pipe or by inserting a hose into the
cold water connection.
Draining the climate system
In order to carry out service on the climate system, it may
be easier to drain the system first. This can be done in
different ways depending on what needs doing:
NOTE
There may be some hot water when draining
the heating medium side/climate system. There
is a risk of scalding.
Draining the heating medium side in the cooling
module
If, for example, the heating medium pump requires re-
placing or the cooling module requires servicing, drain
the heating medium side as follows:
1. Close the shut-off valves to heating medium side
(QM31) and (QM32).
2. Connect a hose to the bleed valve (QM1) and open
the valve. Some liquid will run out.
3. Air must get into the system for the remaining liquid
to run out. To let in air, slacken off the connection
slightly at the shut-off valve (QM32) that joins the
heat pump with the cooling module.
When the heating medium side is drained, the required
service can be performed and/or replacement of any
components carried out.
Draining the heating medium system in the heat
pump
If the heat pump requires servicing, drain the heating
medium side as follows:
1. Close the shut-off valves outside the heat pump for
the heating medium side (return and flow line).
2. Connect a hose to the bleed valve (QM1) and open
the valve. Some liquid will run out.
3. Air must get into the system for the remaining liquid
to run out. To let in air, slacken off the connection
slightly at the shut-off valve that joins the heat pump
with the cooling module (XL2).
When the heating medium side is empty the requisite
service can be carried out.
Draining the entire climate system
If the entire climate system requires draining, do this as
follows:
1. Connect a hose to the bleed valve (QM1) and open
the valve. Some liquid will run out.
2. Air must get into the system for the remaining liquid
to run out. To allow air in, unscrew the bleed screw
on the highest radiator in the house.
When the climate system is empty the requisite service
can be carried out.
54 Chapter 9 | Service
Emptying the brine system
In order to service the brine system it may be easier to
drain the system first. This can be done in different ways
depending on what needs doing:
Draining the brine system in the cooling module
If, for example, the brine pump requires replacing or the
cooling module requires servicing, drain the brine system
by:
1. Close the shut-off valves to brine system (QM33) and
(QM34).
2. Connect a hose to the drain valve (QM2), place the
other opening of the hose in a container and open
the valve. A small amount of brine will flow into the
container.
3. Air must get into the system for the remaining brine
to run out. To let in air, slacken off the connection
slightly at the shut-off valve (QM33) that joins the
heat pump with the cooling module.
When the brine side is empty the requisite service can
be carried out.
Draining the brine system in the heat pump
If the heat pump requires servicing, drain the brine sys-
tem by:
1. Close the shut-off valve outside the heat pump for
the brine system.
2. Connect a hose to the drain valve (QM2), place the
other opening of the hose in a container and open
the valve. A small amount of brine will flow into the
container.
3. Air must get into the system for the remaining brine
to run out. To let in air, slacken off the connection
slightly at the shut-off valve that joins the brine side
with the heat pump at connection (XL7).
When the brine side is empty the requisite service can
be carried out.
Helping the circulation pump to start
1. Shut off, F1255 by setting the switch ((SF1)) to "
2. Remove the front cover
3. Remove the cover for the cooling module.
4. Loosen the venting screw (QM5) with a screwdriver.
Hold a cloth around the screwdriver blade as a small
amount of water may run out.
5. Insert a screwdriver and turn the pump motor
around.
6. Screw in the venting screw (QM5).
7. Start F1255 by setting the switch (SF1) to " " and
check whether the circulation pump works.
It is usually easier to start the circulation pump with
F1255 running, switch (SF1) set to " ". If the circulation
pump is helped to start while F1255 is running, be pre-
pared for the screwdriver to jerk when the pump starts.
".
NIBE™ F1255