DOMESTIC HOT WATER CONNECTION
The DHW tank (secondary) must be filled and pressurised
before filling and pressurising the heating circuit
(primary).
The HeatMaster® TC can be connected directly to the DHW circuit.
Flush the system before connecting the DHW circuit.
The system must be equipped with an approved safety unit including a
7 bar safety valve, a non-return valve and a stop valve.
During the heating process, the domestic water expands and the
pressure increases. As soon as the pressure exceeds the safety valve
setting, the valve opens and discharges. The use of a DHW expansion
tank (minimum 2 litres) will avoid a discharge of water and reduce water
hammer.
The hot water can reach temperatures in excess
of 60°C. This can cause burns. Therefore, we
recommend installing a thermostatic mixing valve
directly after the appliance.
If stop valves are used in the installation, they can cause
pressure waves when they are closed.
To avoid this, use devices to reduce water hammer.
If the HeatMaster® 25 or 35 TC is used to produce hot
water without connection to a heating circuit, an
expansion chamber with a capacity of at least 16 litres
must be incorporated into the primary system (no internal
expansion tank for the HeatMaster® 25 / 35 TC).
KEY
1. Domestic cold water
isolation valve
2. Non-return valve
3. Pressure reducer
4. Safety valve
5. DHW expansion vessel
6. DHW temperature control valve
7. Hot water tap
5
6
7
1
2
3
4
bar
2
1
O
3
4
CONVERSION TO NATURAL GAS OR
PROPANE
As indicated on the data plate, the boiler is factory preset to operate
with G20 or G31 gas.
To convert the boiler to another type of gas, it is necessary to:
• add or remove the cover plate (F)
• adjust the CO
2
• adjust parameters 22 to 28 of the MCBA [see MCBA parameters for the
specialist].
The CO
2
parameters to be set are indicated in the technical data table.
ADDING THE COVER PLATE
1. Turn off the gas and electric power supplies.
2. Unscrew the three-piece coupling (A) from the gas pipe.
3. Unplug the gas valve (B).
4. Dismantle the gas valve-venturi assembly (C).
5. Remove the gas valve from the venturi (D) and position the cover
plate (F) in the centre of the O ring (E).
Conversion propane HeatMaster® 70 / 85 TC
A
C
B
DD
F
E
Make sure you position the O ring correctly (E).
6. Reassemble the gas valve-venturi assembly, following the same
procedure in reverse order.
7. Stick the sticker provided with the conversion kit on the boiler and
check the box to indicate the type of gas to be used with the boiler.
Check that the boiler has no gas leaks while operating.
The conversion of natural gas to propane or the reverse is
not authorized in certain countries such as Belgium.
Refer to the gas categories chart.
Before carrying out the CO
2
setting, it is important to
modify the fan speed parameters.
(See MCBA parameters for the specialist)
INSTALLATION
Cover plate Ø
Gas type
HM 70 / 85 TC
G31 or G30
6.8
EN • 13
664Y5300 • A
E
N
FR
R
U
P
L
DE
IT
ES
N
L
