4
Important Points
Installations must comply with local water authority
bye-laws.
The Rada 566 is suitable for use with either steam
and water or hot and cold water.
Position mixing valve easily accessible for adjustment
and servicing. Install with inlets horizontal and flat
face of cover vertical. Check valves, where fitted,
must be installed in horizontal supply lines with caps
uppermost.
Flush supply lines until water is clear before
connecting mixing valve. Unless water supplies are
known to be clean strainers should be fitted,
positioned so that solids are trapped by screen and
fall to cap end e.g. unsuitable for use in rising
supplies.
Pressures
Minimum:
water 0.15 bar
steam 0.5 bar
Maximum:
water 8.25 bar
steam 7.0 bar
When in use, maintained pressures at inlets must not
exceed ratio of 5:1 (hot and cold water) or 3:1 (steam
and water).
If inlet pressures are unequal and either the outlet is
restricted or less than maximum flow used, due
allowance must be made for resulting increase in
pressure ratio.
Layout and sizing of pipework must be such that
when other services are used, pressures at inlets of
mixing valve are maintained as far as reasonably
possible and do not fall below recommended minimum.
Connections
Inlets/outlet: 1½" BSP.
Connect STEAM or HOT water to inlet marked RED
and COLD water to inlet marked BLUE. Do not
confuse these markings with words hot' and 'cold',
which are cast in the cover as a temperature
regulating instruction.
Flow Control
The mixing valve does not control flow. It must be
fitted with either:-
(a)
Inlet stop valves and unrestricted outlet or
(b)
Inlet check valves and outlet stop cock.
Either method can be used for mixing hot and cold
water, or for mixing steam and water. where water
pressure exceeds steam pressure.
Note: Method (a) must be used when mixing steam
and water where steam pressure exceeds water
pressure. When outlet flow control is used install
conveniently situated isolating valves for servicing
purposes.
If you are in doubt please contact us before
Maximum Temperature Setting
With steam pressure or hot water temperature at
normal, adjust to desired flow rate. Turn temperature
regulating handle to full clockwise position, then
check temperature at discharge point with the
thermometer. If necessary, adjust as follows.
Remove acorn nut (620 11). temperature regulating
handle assembly (916 66) and spring (050 66).
Replace handle (without spring) in mid-position on
spindle, tighten acorn nut. Turn handle clockwise to
increase, or anti-clockwise to decrease temperature,
until required maximum outlet temperature is obtained.
Taking care not to move spindle, remove acorn nut
and handle. Replace spring, replace handle loosely
on spindle and press handle towards cover so spring
is compressed. Again taking care not to turn spindle,
turn handle clockwise until contact with stop plate
(110 66) is made and limit of travel reached.
Tighten acorn and recheck maximum temperature.
Reversed Inlets
If steam or hot water has been connected to cold
inlet and vice versa, this will be indicated by hot
water being obtained when cold is selected and vice
versa. Correct as follows:
Isolate mixing valve. Remove acorn nut, temperature
regulating handle and spring. Undo cover screws and
remove cover. Remove blanking screw (610 11).
Remove fouling plate screw (610 01) and fouling plate
(111 66), re-assembling fouling plate on opposite side
of base and replacing blanking screw in the hole
vacated by fouling plate screw.
Rotate port sleeve (014 68) through 180
o
, so cut-out
is opposite fouling plate. Slacken stop plate screws
(610 09) and turn thermostat assembly through 180
o
.
Tighten stop plate screws but do not over tighten.
Replace cover, locating thermostat assembly actuator
in slot at top of port sleeve. Replace and tighten
cover screws. Re-set maximum temperature. as
earlier described.
Maintenance
Periodical cleaning of internal parts will maintain the
mixing valve in good mechanical order.
Frequent movement of temperature regulating handle
will help keep port sleeve (014 68) from sticking due
to calcereous deposit. A click will be heard as the
port sleeve reaches each limit of travel, indicating
that it is free.
To service mixing valve, first isolate supplies.
Dismantling
1.
Remove acorn nut, temperature regulating
handle and spring. Undo cover screws and lift
off cover.
2.
Slacken stop plate screws (610 09), then
remove thermostat assembly from cover by
pressing on end of spindle. Do not damage
spindle.
Rada 566 thermostatic mixing valve
INSTALLATION AND MAINTENANCE ADVICE
INSTALLER - This leaflet is the property of the customer and must be left with the user.
