4
Set-up and installation
Installation and operating instructions
29
Gas Combi Unit
Floor-standing gas condensing boiler with integrated heat storage
008.1543899_02 – 04/2019 – EN
WARNING (UK ONLY)
If filling or topping up the storage tank is done by means of
the boiler filling and drain valve, a temporary filling loop
must be used with the appropriate backflow prevention
device in accordance with clause G24.2, Guidance to the
Water Supply (Water Fittings) Regulations 1999.
▪
Water shortage protection
: The pressure and temperature mon-
itoring of the GCU compact switches off the gas burner safely in
the event of water shortage (pressure sensor: monitor function)
and locks it (STBK). No additional water shortage protection is
needed in the construction.
▪
Avoid damage caused by deposits and corrosion:
Observe the
requirements on the heating water (see
)
DANGER: RISK OF BURNING
There is a danger of scalding at hot water temperatures
over 60 °C. This is possible when using solar energy if an
external heater is connected, the Legionella protection is
activated, or the hot water target temperature is set to
more than 60 °C.
▪ Install scalding protection (hot water mixer device (e.g.
VTA32)).
4.6.3
Connecting the condensate drain and
storage tank overflow
The condensate produced during the cooling of the combustion
gases in the boiler and in the flue gas system is led to the rear via
the condensate pipe integrated in the storage cover and then dis-
charged into the drainage system via a drain hose to be installed on
site.
A drain hose must also be connected to the overflow of the storage
tank.
1
Drain hoses (not included) with free inflow to the drains connec-
tion.
2
Secure drain hoses with hose clamps on connection nozzles.
3
The complete outlet must not be lockable and must discharge
the condensation and any medium leaking due to damage
(drinking water, buffer or heating water) outwards visibly (e.g.
hose to flow drain or transparent outlet pipe).
4
To avoid heat and water loss, a siphon filled with water must be
used for the overflow hose (see
INFORMATION
The
condensate drain hose
must be routed to the drains
connection
without a siphon
in order to avoid backflow
due to double siphoning. The condensate drain siphon is
integrated in the storage cover. It must be filled with water
before commissioning the device.
5
If local waste water regulations require the condensate to be
neutralised, the condensate drain must be established via a suit-
able neutralisation device.
6
Check the condensate and overflow/drainage section for leaks.
Fig. 4-25
Connection of the drain hoses for condensate drain and
storage tank overflow
4.6.4
Installation of the DB connection kit
The optional DB connection kit allows better access for connecting
the DrainBack pipe (solar feed).
Fig. 4-26
DB connection kit (example shows GCU compact 5xx)
A
DB pipe connection (solar inflow)
B
FlowSensor (not part of the DB connection kit, but included
in Solaris R3 control and pump unit)
C
Flow rate limiter (FlowGuard)
D
Solar inflow connection
on the storage tank
4.6.5
Installation of the P connection kit
The optional P connection kit for Biv device types allows better ac-
cess for connecting the inflow and return flow lines of a pressurised
solar system or another external heat generator on the storage tank.
The kit contains two thermally insulated corrugated pipes that are
connected to the Biv connections of the storage tank via a union nut.
At the other end of the corrugated pipes there is an adapter for dif-
ferent connection sizes of the supply and return pipes.
Summary of Contents for GCU compact Series
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