Safety Valve; Circulation Pump; Application; Control - REMEHA W40 Installation And Maintenance Instructions Manual

7.6.4 Safety valve

A safety valve should be fitted in the flow pipe between
the boiler and any isolating valves but in any case within
0.5 m of the appliance. The safety valve should be sized
according to the requirements given in the current
edition of BS 6644.

7.6.5 Circulation pump

The remeha W40-m ECO is equipped with a circulation
pump, manufactured by Wilo, model RS 25/70 r.
The running power of this circulation pump is:
95 W (position 1) at 2400 rpm.
The pump is adjusted at position 1.
Note:
Pump positions 2, 3 and 4 cannot be used because the
pressure head is too low. This may lead to temperature
faults.
The remeha W60-m ECO is supplied with a circulation
pump, manufactured by Wilo, model RS 30/80 and a
L.L.H. header (see fig. 04) .
The microprocessor programm allows a choice as to
whether the pump operates continuously or whether
there is a pump over-run of 1 - 15 minutes after the
boiler ceases firing.
Both pumps have been selected based on a primary
circulation of 15˚C ∆t.
7.7 D.H.W. application
An indirect calorifier can be connected to the remeha
W40/60-m ECO in accordance with the schematic
sketch shown (fig. 15 and 16) and the wiring diagram in
para. 8.10.
7.7.1 D.H.W. control
The remeha W40/60-m ECO is supplied as standard
with a D.H.W. control suitable for activating a 230 V
spring loaded three-way valve. The three-way valve is
de-energized in the central heating position.
The control features priority D.H.W., which means that
when heat demand comes simultaneously from both the
D.H.W. and the central heating, the D.H.W. takes prece-
dence and is available 24 hours a day completely inde-
pendant of the heating control.
When the D.H.W. demand has been met, the circulation
pump will continue to operate in the D.H.W. position for
approximately 5 minutes, if no heat demand.
The D.H.W. temperature can be controlled by:
a. thermostat (24 V)
b. temperature sensor
For starting up the D.H.W. see para. 10.3.7 - 10.3.11.
Notes:
- To avoid uncontrolled flow in the central heating cir-
cuit, the D.H.W. return piping must never be connected
to the central heating circuit, but should always be con-
nected directly to the return piping on the remeha
W40/60-m ECO.
- Fit the calorifier in accordance to the local authority
requirements.
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