rada 320 c User manual

1
IMPORTANT
Installer: This Manual is the property of the customer and
must be retained with the product for
maintenance and operational purposes.
320 c
PRODUCT MANUAL

2
INDEX
Page
INTRODUCTION 3
DESCRIPTION 3
SAFETY : WARNINGS 3
SPECIFICATION
Important Points 4
Normal Operating Conditions 4
Operating Parameters 4
- Pressures/Flow Rates 4
- Temperatures 5
- Connections 5
- Standard Inlet Configuration 6
- Flow Control 6
DIMENSIONS 6
PACK CONTENTS 7
INSTALLATION
General 8
Outlet position/Reversed inlets 8
Installation 9
COMMISSIONING
Maximum Temperature 11
Maximum Temperature Setting 11
- For Adjustable Temperature 11
- For Locked Temperature 12
Commissioning Checks 13
OPERATION 13
FAULT DIAGNOSIS 14
MAINTENANCE
General 16
Planned Maintenance Programmes 16
(Preventative/Precautionary Maintenance)
Maintenance Procedures 17
- Lubricants 17
- Cartridge Assembly 17
- Check Valve Cartridges 19
- Inlet Filters 21
SPARE PARTS 22
CUSTOMER CARE Back Cover

3
WARNING! Continued use of this product in conditions outside the limits listed in
this section can severely affect the performance and reduce the effective service life,
and can present potential risk to users.
Rada products are precision-engineered and should give continued superior and
safe performance, provided:
1. They are installed, commissioned, operated and maintained in accordance with
the recommendations given in this Manual.
2. Periodic attention is given, as necessary, to maintain the product in good
functional order. Recommended guidelines are given in the MAINTENANCE
section.
The function of a thermostatic mixing valve is to deliver water consistently at a safe
temperature.
In keeping with every other mechanism, it cannot be considered as being functionally
infallible and as such, cannot totally replace the vigilance of nursing/supervisory
staff where that is necessary.
Provided it is installed, commissioned, operated and maintained within these
recommendations, the risk of failure, if not eliminated, is reduced to the minimum
achievable.
SAFETY : WARNINGS
INTRODUCTION
Rada Thermoscopic mixing valves are specified to meet the highest standards of
safety, comfort and economy as demanded by todays users. All Rada products are
designed, manufactured and supported in accordance with accredited BS EN ISO
9001:1994 Quality Systems.
This Manual covers the Rada 320 c valve manufactured from May 1998.
A 3/4" thermostatic mixing valve to suit a wide diversity of applications and installation
formats.
Incorporates the Radatherm cartridge, a unique sealed-for-life unit utilising proven
durability high-technology materials for extended service-free reliability. This cartridge
employs the advanced 2nd generation 'thermoscopic' temperature sensor to provide
water at safe, accurate temperatures for showering or process requirements.
The mixing valve inlets incorporate integral isolating valves, strainers and checkvalves.
For connection to surface pipework, includes angled checkvalve elbows with
integral isolating ball valve. Supplied with compression type connections.
DESCRIPTION

4
SPECIFICATION
Important Points:
1The installation, commissioning and maintenance of this product must be carried
out in accordance with instructions given in this Manual, and must be conducted
by designated, qualified and competent personnel.
2. Installations must comply with all Local/National Water Supply Authority
Regulations/Byelaws, and Building and Plumbing (UK: BS6700) Regulations.
3. Rada products are precision-engineered and should give continued superior and
safe performance, provided:-
- they are installed, commissioned, operated and maintained in accordance with
these recommendations
- periodic attention is given as necessary to maintain the product in good functional
order. Recommended guidelines are given in the MAINTENANCE section.
4. WARNING! Continued use of this product in conditions outside the limits listed
in this section can severely affect the performance and reduce the effective
service life, and can present potential risk to users.
5. Disinfectants: In applications where system chemical disinfection is practised,
chlorine can be used (calculated chlorine concentration of 50mg/l (ppm) maximum
in water, per one hour dwell time, at service interval frequency). Such procedures
must be conducted strictly in accordance with the information supplied with the
disinfectant and with all relevant Guidelines/Approved Codes of Practice.
If in any doubt as to the suitability of chemical solutions, refer to Kohler Mira Ltd,
or Local Agent.
Normal Operating Conditions are considered as:
- inlet dynamic pressures nominally balanced to within 10% of each other during
flow.
- a differential of approximately 50oC between the hot and cold inlet temperatures,
and with differentials of 15-35oC between the blend setting and either supply.
- daily usage of 1 - 6 hours.
- installation and usage environment not subject to extremes of temperature,
unauthorised tampering or wilful abuse.
Operating Parameters
Pressures/Flow Rates
For optimum performance, dynamic supply pressures should be nominally equal.

5
Minimum Recommended Flow Rate: 6 l/min at mid-blend with equal dynamic
supply pressures.
Maximum Recommended Flow Rate: 120 l/min.
Maximum Recommended Pressure Loss Ratio*: should not exceed 10:1, in
favour of either supply, during flow.
Maximum Static Pressure: 10 bar.
Maximum Dynamic/Maintained Pressure: 5.6 bar.
Minimum Pressure Loss: 0.1 bar.
Flow Rate/Pressure Loss Graph
Temperatures
Optimum Thermostatic Control Range: 30 - 50oC.
Minimum Cold Water Temperature: 1oC.
Maximum Hot Water Temperature: 85oC.
Connections
320 c -Inlets: 3/4" BSP female thread/22 mm compression (compression
fitting supplied)
-Outlet: 3/4" BSP female thread/22 mm compression (compression
fitting supplied)
Flow Rate
Litres/Min.
Pressure Loss - bar
80
01.0 3.0 4.0
2.0
60
40
0
100
120
6.0
5.0
20
*PressureLossRatioisdeterminedbysubtractingtheresistancetoflowoftheoutlet
pipeworkandoutletfittings(generallyknownas"backpressure",andmeasuredatthe
outlet of the mixing valve) from the dynamic pressures of the hot and cold water at
each inlet of the mixing valve. This is at its extreme when the mixing valve is being
usedatitslowestflow-rateandwhenthemaximuminequalityoccursinthepressure
of the hot and cold water supplies.

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Standard Inlet Configuration
hot - left (marked red)
cold - right (marked blue)
Flow Control
Rada 320 c mixing valves do not have integral flow control; appropriate provision
must be made for this in the outlet pipework.
This can be in the form of stop-cock, mechanical timed-flow controller or solenoid.
The device chosen must be non-concussive in operation.
DIMENSIONS
180 mm
63.3 mm
222 mm
82.5 mm Dia
187.5 mm
52 mm
82.5 mm Dia

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PACK CONTENTS
Tick the appropriate boxes to familiarize yourself with the part names and to
confirm that the parts are included.
Rada 320 c
1 x 320 c 
1 x 3 mm
Hexagonal Wrench
3 x Olives 
3 x Compression Nuts 
1 x Product Manual 
4 x Screws 
3 x Fittings 

4 x Wall Plugs 


8
INSTALLATION
General
Installation must be carried out in accordance with these instructions, and
must be conducted by designated, qualified and competent personnel.
1. Before commencing, ensure that the installation conditions comply with the
information given in SPECIFICATION.
2. Care must be taken during installation to prevent any risk of injury or damage.
3. The mixing valve should be positioned for easy access during use and
maintenance. All routine maintenance procedures can be conducted with the
mixing valve body in place. For all models, allow a minimum 100 mm clearance
in front of the temperature control to enable removal of the Radatherm cartridge
during maintenance.
4. The use of supply-line or zone strainers will reduce the need to remove debris
at each mixing valve point. The recommended maximum mesh aperture
dimension for such strainers is 0.5 mm
5. Pipework must be rigidly supported.
6. Long pipework dead-legs may effect shower performance.
7. Supply pipework layout should be arranged to minimise the effect of other outlet
usage upon the dynamic pressures at the mixing valve inlets.
8. Inlet and outlet threaded joint connections should be made with PTFE tape or
liquid sealant. Do not use oil-based, non-setting jointing compounds.
9. To eliminate pipe debris it is essential that supply pipes are thoroughly
flushed through before connection to the mixing valve.
10. Inlet isolators must be used in the fully open position.
11. Do not install the Rada 320 c in a position where it may become frozen.
Outlet Position/Reversed Inlets
All Rada 320 c mixing valves are supplied with the inlet connections configured hot
- left, cold - right, and top outlet as standard.
Should the existing hot and cold pipework make this configuration inconvenient then
remove the cartridge assembly and turn it through 180o(Refer to MAINTENANCE
for cartridge removal and re-assembly).
If a bottom outlet position is required, remove the blanking cap from the bottom of
the valve and replace it with the fitting from the top of the valve. Then fit the blanking
cap to the top of the valve.

9
Installation
Rada 320 c models have easily adjustable inlet elbows to accommodate rising or
falling supplies.
1. When unpacked, the inlet elbows are positioned to accept falling supplies. Should
the installation require rising supplies then the inlet elbows will need adjusting.
- Loosen each inlet elbow grub screw using the 3 mm hexagonal wrench (supplied).
Note! Each inlet elbow has two grub screws, one for removal of the isolator
assembly and one for removal of the inlet elbow.
- Pull the inlet elbow away from the valve body and refit in the desired position.
- Loosen isolator assembly grub screws and position so that the isolator is
accessible.
- Tighten the grub screws.
2. Loosen the backplate grub screws (3 off) using the 3 mm hexagonal wrench
(supplied) and remove the backplate.
3. Fix the backplate securely to the wall surface using the fixing screws and wall
plugs provided.
4. Important!Flush through the hot and cold supplies thoroughly before connection
to the valve.
5. Fit the valve onto the backplate and tighten the grub screws (3 off).
6. Connect the hot, cold and outlet supplies using the fittings, olives and compression
nuts supplied and check for any leaks.
7. The maximum temperature may now need resetting. Refer to COMMISSIONING.

10
Backplate
Isolation
Screw
Isolator
Assembly
Compression
Nut
Olive
Wall Plugs
Fixing Screws
Grub Screw
Fitting
Inlet
Pipework
Inlet
Pipework
Outlet
Pipework
Inlet Elbow
Grub Screw
(for removal of
inlet elbow)
Isolator Assembly
Grub Screw

11
COMMISSIONING
Commissioning must be carried out in accordance with these instructions,
and must be conducted by designated, qualified and competent personnel.
Maximum Temperature
The maximum blend temperature obtainable by the user should be limited, to prevent
accidental selection of a temperature that is too hot.
All Rada Thermostatic mixing valves are fully performance tested and the maximum
temperature is preset to approximately 43oC under ideal installation conditions at
the factory.
Site conditions and personal preference may dictate that the maximum temperature
has to be reset following installation.
Maximum Temperature Setting
Check that an adequate supply of hot water is available at the hot inlet of the mixing
valve.
Note! The minimum temperature of the hot water must be at least 12oC above the
desired blend, however during resetting this should be close to the typical storage
maximum to offset the possibility of any blend shift due to fluctuating supply
temperatures.
Check that both inlet isolating valves are fully open.
Temperatures should always be recorded using a thermometer with proven accuracy.
For Adjustable Temperature
1. Remove the temperature knob concealing cap and then the screw using the 3
mm hexagonal wrench (supplied). Remove the temperature knob.
2. Pull off the hub.
3. Rotate the spindle until required maximum blend temperature is obtained at outlet
point (clockwise = decrease temperature, anticlockwise = increase
temperature)(refer to Figure 2).
When resistance is felt do not use force to turn any further, as this will
damage the internal parts.
4. Once the desired maximum blend temperature is achieved, refit the hub without
disturbing the spindle: Position the hub so that the hub stop comes up against
the cartridge stop (refer to Figure 2) preventing any further rotation in an
anticlockwise direction. Check that blend temperature has not altered.
5. Refit the temperature knob. Make sure that the indicator points to 9 o'clock.

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For Locked Temperature
1. First, remove the temperature knob concealing cap and then the screw using the
3 mm hexagonal wrench (supplied).
2. Pull off the hub.
3. Rotate the spindle until required maximum blend temperature is obtained at
discharge point (clockwise = decreasetemperature, anticlockwise= increase
temperature).
When resistance is felt do not use force to turn any further, as this will
damage the internal parts.
4. Once the desired maximum blend temperature is achieved, refit the hub without
disturbing the spindle, positioning it so that the centre stop slot in the hub fits
over the top of the cartridge stop (refer to Figure 2), preventing further rotation.
Check that blend temperature has not altered.
5. Refit the temperature knob. Make sure that the indicator points to 6 o'clock.
Temperature Knob
Hub
Screw
3 mm Hexagon
Wrench
Spindle
Cartridge Stop
Centre Stop Slot
Centre Stop Position
Hub Stop
Hub Stop Position
Hub Stop
Inner Face
Outer Face
Increase
Temperature
Decrease
Temperature
Indicator
Concealing
Cap

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OPERATION
For models with knob fitted for adjustable temperature control, adjustment of blend
temperature from preset maximum to cold is achieved by clockwise rotation of the
knob.
For models with locked temperature control, no user adjustment is intended.
Control of flow is via separate outlet valve(s), refer Flow Control.
Commissioning Checks
(Temperatures should always be recorded using a thermometer with proven
accuracy).
- Check inlet pipework temperatures for correct function of checkvalves.
- Operate the outlet flow control and check:
1. Flow rate is sufficient for purpose.
2. Temperature(s) obtainable are acceptable.
3. All connections and mixer body are water tight.
- It is advisable to establish a performance check at this time, which should be
noted for future reference as part of a Planned Maintenance Programme (a
Maintenance Record Card has been provided with this Manual).
The procedure should be chosen to imitate both typical and difficult operating
conditions, such as any supply pressure fluctuations that may be likely. An
ideal method is to locate another outlet on the common cold water supply close
to the mixing valve (operating this outlet may cause a drop in supply pressure),
and subsequently have a temporary effect on blend temperature (should be no
more than 2oC change).
Note! Causing thermal shutdown of the mixer by full closure of the cold supply may
not adequately indicate the practical capability of the mixer, nor its service condition.
Consequently this is not a recommended performance check, and repeated such
testing may ultimately affect service life.

14
FAULT DIAGNOSIS
Symptom Cause/Rectification
1. Only hot or cold
water from outlet.
a. Inlet supplies reversed (i.e. hot supply to cold inlet).
Check.
b. No hot water reaching mixing valve. Check
c. Check filters and inlet fittings for blockage.
d. Refer symptom 5below.
e. Installation conditions continuously outside operating
parameters: refer to SPECIFICATION and 2e below.
2. Fluctuating or
reduced flow
rate.
3. No flow from
mixing valve
outlet.
a. Check filters and inlet/outlet fittings for blockage.
b. Hot or cold supply failure; thermostat holding correct
shutdown function: rectify, and return to 2e above.
4. Blend
temperature drift.
Check inlet isolators are fully open.
5. Hot water in cold
supply or vice
versa.
Indicates check valves require maintenance, refer to
MAINTENANCE.
6. Maximum blend
temperature
setting too hot or
too cool.
a. Indicates incorrect temperature setting; refer to
COMMISSIONING.
b. As symptom 4 above.
c. As symptom 5 above.
Normal function of mixing valve when operating conditions
are unsatisfactory.
Indicates operating conditions changed.
a. Refer to symptom 2 above.
b. Hot supply temperature fluctuation (rectify and refer to
COMMISSIONING).
c. Supply pressure fluctuation (refer to INSTALLATION;
General).
a. Check filters and inlet/outlet fittings for flow restriction
(check isolators are fully open).
b. Ensure that minimum flow rate is sufficient for supply
conditions.
c. Ensure that dynamic inlet pressures are nominally
balanced.
d. Ensure that inlet temperature differentials are sufficient.
e. (subsequent to rectification of supply conditions) Check
thermostatic performance; renew cartridge assembly if
necessary.
(Continued)

15
Symptom Cause/Rectification
7. Water leaking
from valve body.
Seal(s) worn or damaged.
a. Obtain Seal Pack, and renew all seals.
b. (If leak persists from around temperature spindle).
Renew cartridge assembly.
(Continued)

16
MAINTENANCE
General
Rada products are precision-engineered and should give continued superior and
safe performance, provided:
1. They are installed, commissioned, operated and maintained in accordance with
our recommendations.
2. Periodic attention is given as necessary to maintain the product in good functional
order. Guidelines for frequency are given below.
All functional parts (except the temperature or locking knob) are contained within
service-free cartridges, so any maintenance requirement is reduced to temperature,
performance and functional checks and inspection, with cartridge renewal when
necessary. In larger installations with a number of mixing valves, it is good policy to
maintain a small stock of spare cartridges so that no mixing valve or facility need be
out of commission for more than the time it takes to exchange the cartridge, and
also, eventually, a rolling programme of cartridge renewal can be undertaken as part
of a planned maintenance procedure. The designed minimum service life of all
cartridges is five years under normal operating conditions (refer to SPECIFICATION).
The use of main supply-line or zone strainers (recommended maximum mesh
aperture dimension is 0.5 mm) will reduce the need to remove debris at each mixing
valve point.
Rada Service Engineers/Agents will call by prior arrangement, if required. Service
Contracts may be undertaken, subject to survey - details upon request.
(Preventative/Precautionary Maintenance)
The frequency and extent of attention required will vary according to prevailing site
and operational conditions however, the following guideline schedule is suggested
to cover average duty and site conditions:
Six Monthly
Blend Temperature: check for correct blend setting and/or maximum preset
temperature. Reset as necessary.
Performance:check blend stability against known datum (e.g. commissioning check)
for an induced pressure or flow change. Renew cartridge assembly when necessary.
Function:check inlet pipework temperature for correct function of checkvalves, and
maintain/renew as necessary. Check and clean filters as appropriate. Lubricate
accessible seals when necessary using silicone-only based lubricant.
Planned Maintenance Programmes

17
Maintenance Procedures
Maintenance must be carried out in accordance with these instructions, and
must be conducted by designated, qualified and competent personnel.
This mixing valve is designed for minimal maintenance under conditions of normal
use.
External surfaces may be wiped clean with a soft cloth, and if necessary, a mild
washing-up type detergent or soap solution can be used.
Warning! Many household and industrial cleaning products contain mild abrasives
and chemical concentrates, and should not be used on polished, chromed or plastic
surfaces.
Should an internal malfunction occur then this will probably require cartridge renewal.
The cartridge assembly and check valves contain no user-serviceable parts, and
must not be dismantled.
Components are precision-made, so care must be taken while servicing to avoid
damage.
When ordering spare parts, please state product type, i.e. Rada 320 c, and identify
part name and number (refer to PARTS LIST). A Seal pack is available, containing
all the seals that may be necessary for renewal during maintenance or servicing.
Lubricants
Important! All seals are pre-lubricated. If you need to lubricate the seals, use
only a small amount of silicone-only based lubricants on this product. Do not
use oil-based or other lubricant types as these may cause rapid deterioration of
seals.
Maintenance Procedure - Cartridge Assembly
Removal
1. Turn the isolation screw on the isolator valves through 90 oto isolate the water
supplies to the valve (refer to Figure 4). Open an outlet fitting to release pressure
and to assist the draining of residual water.
2. Remove the temperature knob concealing cap and then the screw using the 3
mm hexagonal wrench (supplied). Remove the temperature knob, the temperature
indicating ring and the hub.
3. Remove the six screws holding the cartridge assembly into the body.
4. Use a suitable tool inserted into the cut-outs to lever the cartridge assembly from
the body.
5. Remove the cartridge assembly from the body.

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Cleaning/Renewal of Parts
6. The interior surface of the mixing valve body must be clean before refitting the
cartridge. Rinse the valve interior thoroughly in clean water to remove any debris
before refitting the cartridge.
Note! The body interior must be cleaned carefully and not damaged in any way.
Do not use any abrasive material.
7. Cartridges may only be cleaned by flushing through under a jet of clean water to
remove debris.
Do not descale. Descaling solution MUST not be used on any parts of the
320 valve. Cartridges are not serviceable, and must not be dismantled.
Cartridges cannot be tested in isolation, service condition should be assessed
as part of the performance check; refer Commissioning Checks.
8. Examine all accessible seals for signs of deformation or damage, and renew as
necessary, taking care not to damage the seal grooves.
Re-assembly
9. Identify which is the hot inlet to the mixing valve body, and align the cartridge
assembly accordingly.
Note! There is a 'H' and 'C' marked on the cartridge. Make sure that the 'H' aligns
with the hot inlet and that the 'C' aligns with the cold inlet (refer to Figure
3).
Align the cartridge guides (refer to Figure3) with the slots in the body and carefully
push the cartridge assembly back into the body, checking that the 2 cartridge
inlet port seals remain in place.
10. Install the six screws and tighten.
11. Fit the temperature indicating ring.
12. Turn the isolation screw on the isolator valves through 90 oto restore the water
supplies to the valve and check for any leaks.
13. Before fitting the hub, the temperature will need resetting; refer to
COMMISSIONING.
14. Secure the temperature knob.

19
Radatherm Cartridge Removal
Figure 3
Temperature Knob
Temperature Indicating Ring
Hub
Screw
Screw
Cartridge Assembly
3 mm Hexagon
Wrench
Body
Cartridge Cut-out To
Aid Removal
'H' and 'C' marked
on cartridge. Make
sure that the 'H' is
lined up with the hot
inlet and that the 'C'
is lined up with the
cold inlet
Cartridge Guides
Temperature Spindle
Maintenance Procedure - Check Valve Cartridges
Hot water entering the cold supply, or vice versa, indicates that immediate attention
is necessary. This is carried out by removing and cleaning, or renewing as necessary,
the two check valves.
1. Turn the isolation screw on the isolator assemblies through 90 o(refer to Figure
4) to isolate the water supplies to the valve. Open an outlet fitting to release
pressure and to assist the draining of residual water.
2. Loosen the isolator grub screws and remove the isolator assemblies from the
inlet elbows.
Note! If necessary, loosen the three grub screws that hold the valve body onto
the backplate and undo the outlet compression fitting. This is so that you can
lower the body away from the backplate. This will give enough clearance to
remove the isolator assemblies from the inlet elbows.
Concealing
Cap

20
3. Remove the inlet elbow grub screws and remove the inlet elbows.
4. Unscrew and remove the check valve housings.
5. Push out the check valves.
The check valve is not a serviceable item, so any apparent wear or damage
will require its renewal.
6. Re-assembly into the valve is a reversal of the above procedures.
7. Turn the isolation screw on the isolator assemblies through 90 o(refer to Figure
4) to restore the water supplies to the valve and check for leaks.
Check Valve Cartridges
Figure 4
Backplate
Isolation Screw
Isolator
Assembly
Valve Body
Check Valve Housing
Check Valve
3 mm Hexagon
Wrench
Grub Screw
Grub Screw
Inlet Elbow
Isolator
Open
Isolator
Closed