HAMWORTHY HEATING LTD
Page
DORCHESTER DR-SE
500001062/D
3
service pipe by the responsible gas conveyor, or his
contractor.
6.3 Gas Supply Pipes
Supply pipes must be fitted in accordance with BS
6891. Pipework from the meter to the heater must be
of adequate size and not smaller than the heater gas
connection (
½
” BSP).
6.4 Boosted Supplies
Where it is necessary to employ a gas pressure
booster, the controls must include a low pressure cut-
off switch at the booster inlet. The responsible gas
conveyor must be consulted before a gas pressure
booster is fitted.
7.0 FLUE SYSTEM
7.1 The Hamworthy DR-SE series of water heaters
are designed to be used with natural draught flues.
Flue systems must be designed in accordance with
the current regulations and with reference to BS 5440
Part 1, BS 6644 and IGE/UP/10. The following points
should be noted:
7.1.1 The correct draught diverter is packed with each
heater. It must be fitted in an unmodified condition to
the spigot on the top of the heater. The draught di-
verter should be pushed fully home into the spigot and
the close fit should ensure no further sealing of this
joint is required.
7.1.2 Any flue system connected to the draught di-
verter must be self-supporting and fitted inside the
diverter top spigot.
Allowance must be made in the
5.0 LOCATION
The heater location should be such that a satisfactory
flue system can be connected. An adequate air supply
for both combustion and ventilation must be provided
(see table 3) and sufficient space allowed around the
heater for servicing (see figure 1). The heater must
normally be installed in a room separate from a living
room. If the heater is to be installed in a living room, it
must be fitted with a combustion products discharge
safety device, which is available as an additional kit—
see Section 15.4 of this manual.
The heater must be installed on a level concrete floor
or plinth or equivalent non-combustible surface which
is sufficient to support its weight when filled with water
(see Table 1).
Any combustible material adjacent to the heater and
flue system must be so placed or shielded so as to
ensure that its temperature does not exceed 65°C
6.0 GAS SUPPLY
6.1 Service Pipes
The responsible gas conveyor must be consulted at
the installation planning stage in order to establish the
availability of an adequate supply of the appropriate
gas.
An existing service pipe must not be used without
prior consultation with the responsible gas conveyor.
6.2 Meters
If necessary a new gas meter will be connected to the
MODEL
DR-SE 18
DR-SE 20
Input (Gross)
22.2 kW
25.5 kW
Input (Net)
20.0 kW
23.0 kW
Output
18.0 kW
20.0 kW
Weight (filled)
470 kg
600 kg
Maximum water pressure
6 bar
6 bar
Nominal gas inlet pressure (G20)
20 mbar
20 mbar
Maximum gas inlet pressure (G20)
25 mbar
25 mbar
Gas burner setting pressure
13.6 mbar
13.0 mbar
Injector diameter
3.5 mm
3.8 mm
Injector marking
350
380
Gas flow rate
2.1 m³/h
2.4 m³/h
Capacity
300 litres
400 litres
Continuous output with
▲
t of 44°C
350 l/h
390 l/h
Time to recover storage with
▲
t of 44°C
52 min
62 min
Table 1. Technical Data
Detailed dimensions of the heaters are shown in Fig. 1
