2
6. The Tundish (E), which shows visible
discharge from the Relief Valves, is to
be in a prominent, visible and safe
position away from any electrical
devices (likewise with the drain
connection) and within 500mm of the
Temperature & Pressure Relief Valve
(D). Pipework from the Tundish (E)
must initially be vertical for a minimum
of 300mm where possible and then
have a continuous fall in excess of 1
in 200. Pipework away from the
Tundish (E) should be in a minimum of
22mm, of material suitable for
temperatures of 95°C and have a
resistance to flow of water not greater
than that of a straight pipe of 9 metres
(each bend or elbow is equal to 0.8
metre of resistance). See BBA
Information. Sheet No 33:1989 for
further details - available from the
manufacturer. Also note page 9 of
these instructions.
7. The Expansion Vessel (F) charged at
2.1 Bar, should either be fitted directly
to connection (M) on the cylinder, or if
space dictates, securely to the wall
with the optional remote fixing kit and
the hose fitted between the vessel and
connection (M).
8. Connect the 3kW 11” 240V Immersion
Heater/s BSEN 60335/2/73 (with
manual re-set cut out at 80°C) to the
power supply and earth them in
accordance with the current IEE wiring
regulations. The fuse rating should be
13 Amps. Do not at any time fit
Immersion Heaters without a thermal
cut-out.
9. On Indirect Units where a Coil is fitted
to the cylinder, the supplied Two Port
Motorised Zone Valve and Dual
Thermostat Controller (J) must be
fitted in accordance with the
instruction details supplied with them
for the appropriate installation.
N.B. Indirects, are suitable for oil,
gas and electric fired boilers on a
pumped, gravity or sealed system.
(We would however recommend
28mm Coil connections with a 28mm
Zone Valve on gravity systems).
Maximum working pressure of the
coil is 3.5 Bar. All electrical wiring to
thermostats, zone valve and
immersion heaters must be earthed
and to current IEE Wiring Regulations.
The fuse should generally be 3 Amps
but refer to appliance instructions to
confirm this.
10. The SecondaryReturn (L) if supplied,
should be plugged if not required. If
the Secondary System pipe-work is
greater than 15% of the unit capacity,
alarger Expansion Vessel may need
to be fitted - contact McDonald
Engineers.
11. Immersion Heaters (H) and the Dual
Aquastat Controller (J) supplied with
the Indirect units should be set to no
greater than 60°C and the internal
High Limit Thermostats are factory set
no higher than 85°C. Always check
this before switching on power.
Please see the checklist on page 4
to ensure all controls are present
and correct.
