Armstrong 320 Instruction Manual

Model No. q Model 320
q Model 320D
Serial No. :
Ship Date :
Model 320
Installation and Maintenance
Water Temperature Controls
Groups of Fixtures - Thermostatic
Keep this manual with installation for
future reference.
Armstrong International
221 Armstrong Blvd., Three Rivers, Michigan, 49093 - USA
armstronginternational.com/brain

2
Introduction.............................................................. 3
Specications .......................................................... 5
General Advisory ..................................................... 5
Safety ...................................................................... 6
Pack Contents ......................................................... 7
Schematic Piping..................................................... 8
Installation ............................................................... 9
General................................................................ 9
Installation Requirements.................................... 9
Tools Required .................................................... 9
Installation Procedure........................................ 10
Commissioning...................................................... 12
Operation............................................................... 13
Servicing & Maintenance....................................... 14
Spare Parts............................................................ 17
Troubleshooting..................................................... 20
Notes ..................................................................... 22
Limited Warranty and Remedy .............................. 24
Contents

3
Thermostatic Mixing Valves (LPM and BAR)
Model
320
Pressure Drop (BAR) Min.
Flow CV
0.3 0.7 1.0 1.4 1.7 2.1 2.4 2.8 3.1 3.4
LPM 30.3 41.6 49.2 56.8 64.4 71.9 75.7 83.3 87.1 90.8 3.8 3.4
Thermostatic
Model 320
Thermostatic Mixing Valve of “sealed for life” disposable
cartridge construction. Compact design with top and/or bottom
blended water outlet makes the Model 320 ideal for recessed
enclosure, plumbing chase and utility/mechanical room
installation.
Complete operating mechanism of valve is enclosed in a
durable polymer cartridge for ease of field maintenance.
Powerful internal mechanism and non metallic wetted parts
resist mineral deposition.
Capable of close temperature control at diverse flow rates
between 1 gpm (3.8 lpm) and 24 gpm (91 lpm). Able to blend
within 5°F (2°C) of either inlet supply due to “low seepage”
across internal proportioning mechanism.
Operational Specifications
• Dual thermostatic elements provide redundancy in the
event of individual thermostat failure
• Typical outlet temperature control +/-2°F
• Adjustable maximum temperature limit stop
• Adjustable single temperature lockout
• Thermal shutdown mode upon inlet supply failure
Technical Specifications
• 3/4” MNPT inlets and 3/4” MNPT outlet
• Chrome-plated brass/polymer construction
• Lead Free compliant
• Operating pressures
Maximum: 150 psi (10 bar)
Minimum: 10 psi (.7 bar)
• Integral inlet check valves and strainers
• ASSE 1017 and CSA B125 certified
• Shipping weight 10 lbs (4.5 kg)
Thermostatic Mixing Valves (GPM and PSI)
Model
320
Pressure Drop (PSI) Min.
Flow CV
5 10 15 20 25 30 35 40 45 50
GPM 8 11 13 15 17 19 20 22 23 24 1.0 3.4
Designs, materials, weights and performance ratings are
approximate and subject to change without notice. Visit
armstronginternational.com for up-to-date information.
Armstrong Hot Water Group, 221 Armstrong Blvd., Three Rivers, MI 49093 – USA
Phone: [phone], Fax: [phone]
Water Temperature Control - Groups of Fixtures
4.61
(117.0)
7.29
(185.2)
1.04
(49.3)
5.38
(136.6)
HOT
INLET
COLD
INLET
MIXED
OUTLET

4
Thermostatic Mixing Valves (GPM and PSI)
Model
320D
Pressure Drop (PSI) Min.
Flow CV
5 10 15 20 25 30 35 40 45 50
GPM 8 11 13 15 17 19 20 22 23 24 1.0 3.4
Designs, materials, weights and performance ratings are
approximate and subject to change without notice. Visit
armstronginternational.com for up-to-date information.
Armstrong Hot Water Group, 221 Armstrong Blvd., Three Rivers, MI 49093 – USA
Phone: [phone], Fax: [phone]
Thermostatic
Model 320D
A derivative of the standard Model 320 Thermostatic Mixing
Valve for institutional group fixture control. Compact design with
top and/or bottom blended water outlet makes Model 320 ideal
for recessed enclosure, plumbing chase and utility/mechanical
room installation.
Factory supplied pre-plumbed and pressure-tested Model
320D is supplied as standard with inlet check valves, strainers,
unions, isolations valves and outlet thermometer and stop
valve*.
*Model 320D is supplied with top outlet and can be site
reconfigured for bottom outlet applications.
Operational Specifications
• Dual thermostatic elements provide redundancy in the
event of individual thermostat failure.
• Typical outlet temperature control +/-2°F
• Adjustable maximum temperature limit stop
• Adjustable single temperature lockout
• Thermal shutdown mode upon inlet supply failure
Technical Specifications
• 3/4” NPT inlets and 3/4” NPT outlet
• Chrome plated brass/polymer construction with self finish
brass and bronze lead free components
• Lead Free compliant
• Operating pressures
Maximum: 150 psi (10 bar)
Minimum: 10 psi (.7 bar)
• Inlet check valves, strainers, unions and isolation valves
• Fitted with outlet thermometer and isolation valve
• ASSE 1017 and CSA B125 certified
• Shipping weight 18 lbs (8.1 kg)
For a submittal drawing, refer to D61051.
Water Temperature Control - Groups of Fixtures
Thermostatic Mixing Valves (LPM and BAR)
Model
320D
Pressure Drop (BAR) Min.
Flow CV
0.3 0.7 1.0 1.4 1.7 2.1 2.4 2.8 3.1 3.4
LPM 30.3 41.6 49.2 56.8 64.4 71.9 75.7 83.3 87.1 90.8 3.8 3.4
7.6
(194)
3.8
(97)
TYP
12.2
(311)
7.8
(198)
TYP

5
Specications
*Model 320 can accept temporary excursions above 185°F (85°C) and maintain control without sustaining
internal damage. (ASSE 1017 certification requires exposure to 200°F (93°C) for a period of 30 minutes).
Prolonged operation of the Mixing Valve at such elevated temperatures is not recommended.
** Normal operating conditions are considered as a differential of approximately 122°F (50°C) between
the hot and cold inlet temperatures, and with differentials of 59°F (15°C) - 95°C (35°C) between the
blend setting and either supply. 59°F (15°C) is the optimum published minimum differential required to
achieve full thermal performance.
General Advisory
This Model 320 Valve has been supplied for this application based upon information provided to Armstrong at the
time the order was placed.
This Model 320 Valve is configured for use in a “dead-leg” piping configuration.
This Model 320 Valve has not been congured for use in a central pumped re-circulation system.
This Model 320 Valve is not designed to deliver tepid water to emergency fixtures.
For further information, please call our technical department 1-269-279-3602 between 08:00 a.m. to
05:00 p.m. EST.
Operating Specications
Maximum Hot Water Supply Temperature185° 158°F (70°C)*
Minimum Cold Water Supply Temperature33° 33°F (1°C) - 77°F (25°C)
Optimum Minimum Inlet to Outlet Temperature Differential 59°F (15°C)**
Optimum Thermostatic Control Range 86°F (30°C) - 122°F (50°C)
Flow Rate at 45 psi 23 gpm (87 lpm)
Minimum Flow Rate 1 gpm (3.8 lpm)
Maximum Inlet Supply Pressure 150 psi (10 bar)
Minimum Inlet Supply Pressure 10 psi (0.7 bar)

6
Safety
Applicable codes must be followed and supersede any other instructions.
Generally applicable codes in the US include:
• IPC (International Plumbing Code)
Read this manual
Improper installation or operation may cause a ood resulting in property
damage, personal injury, or death. Armstrong strongly recommends that
a qualied installer be used.
Service must be performed by a qualied person.
Improper installation, start-up, operation, maintenance, or service may
void the warranty.
Hot water or metal may cause scald burns. Skin exposure to 140°F water
or metal for only ve seconds may cause a second degree burn.
Icon Legend
If instructions are not followed:
- injury or death and property damage are imminent
- injury or death and property damage are possible
- potential property damage, expensive repairs, and/or voiding
the warranty may result
The function of a Thermostatic Mixing Valve is to deliver water consistently at a pre-designated temperature.
Model 320 Thermostatic Mixing Valves are precision engineered to give continued superior and safe
performance provided:
1. They are installed, commissioned, operated and maintained in accordance with the recommendations
provided and accepted plumbing practices.
2. Periodic attention is given, as necessary, to maintain the product, the accessory fittings and the plumbing
system in good functional order.
In keeping with every other mechanical product, Model Mixing Valves should not be considered as
functionally infallible and, as such will never totally replace the vigilance and attention of facility nursing/
bathing or other institutional supervisory or industrial safety staff.
Provided that they are installed, commissioned, operated and maintained, the risk of product failure and
its associated consequences, if not eliminated, are reduced to the minimum achievable.

7
Pack Contents
X 1 
X 1 
X 1 
X 3 
X 1 

8
Schematic Piping
Hot Water Supply
Water Heater
Model 320
Mixed Flow
Cold Water Supply
System Layout
Thermometer
Sink
Shower
Check Valve
Isolation Valve
Stop Valve
Flow Direction
Pipeline

9
Installation
General
Installation must be carried out in accordance with these instructions, and must be conducted by designated,
qualied and competent personnel.
The installation must comply with all relevant local and state water plumbing codes.
All plumbing components are to be supplied by the installer. Failure to include these components will compromise
the product, system performance and will void the warranty.
Notes:
1. Model 320 is supplied fully performance and pressure tested.
2. Suitable connections for ease of maintenance should be used on the inlet and outlet ports. (Isolation valves
and unions.)
3. The hot and cold water inlet supply pressures must be nominally equal.
4. The inlet supply pipework must be thoroughly ushed before tting the Model 320 valve.
5. The Model 320 can be installed in both rising supplies and falling supplies.
Installation Requirements
1
2
3
4
5
The use of supply strainers will reduce debris entering the Model 320. The recommended gauge for such
strainers is 35 mesh (mesh aperture dimension = 0.5mm).
Inlet pressure tappings which allow measurement of the inlet pressures to the Model 320 under operating
conditions are particularly recommended for in-service testing.
Pipework must be rigidly supported to avoid any strain on the connections.
Inlet and outlet threaded joint connections should be made with PTFE thread sealing tape or liquid sealant.
Do not use oil-based, non-setting joint compounds.
Run water for 1 minute from both hot and cold supplies to eliminate pipe debris. It is essential that supply
pipes are thoroughly ushed through before connection to the Model 320.
Tools Required
Driling Drill Bit Screw Driver Pencil Adjustable Allen Keys Safety
Machine size 6 mm Plus & Minus Spanner 3mm & 2.5mm Glasses

10
1
3
4
2
Ø 6 mm
a. Unscrew the set screw.
b. Remove the Backplate.
a. Use the Backplate to mark the four mounting holes at
the desired height.
b. Drill the holes (6 mm) and t the wall anchors. Screw
the Backplate to the wall.
Caution! Avoid area where underground wirings
or pipelines pass through.
a. Mount the Valve assembly on the Backplate xed on
the wall. Make sure the Valve assembly locks in the
groove.
b. Tighten the set screw.
a. Important! Prior to assembly of the hot and cold
adapters, look inside each one and ensure that there
is a strainer and a white plastic checkvalve. The
adapter with nothing inside is for the outlet.
Thread the coupling nuts onto the Valve assembly
then tighten using an adjustable spanner.
Caution! Use a soft cloth to protect the plating
from damage while tightening the spanner.
Step 1
Step 3
Step 2
a
b
Step 4
2.5 mm
2.5 mm
6.0 mm

11
Step 5
Step 7Step 6
a. Fully tighten all of the pipes using an adjustable spanner.
Caution! Use a soft cloth to cover the plating from
damage while tigtening with spanner.
a. Turn on the water supply and ensure that there are
no leaks.
Model 320 must be installed in a standard HOT-LEFT/COLD-RIGHT inlet supply conguration.
There are red (hot) and blue (cold) markings on each valve.
The inlet supplies must always match the corresponding inlet ports on the valve.

12
Model 320 is designed for two types of congurations:
1. Locked Temperature (Temperature control is locked and cannot be adjusted)
2. Adjustable Temperature (Temperature can be adjusted through a desired range)
The following steps show the procedure for both type of installations:
Step 1 Step 2
a. Remove the concealing cap.
b. Unscrew the knob using a 3mm Allen Key.
c. Remove the Knob and Hub.
Step 3
Obtain the desired maximum blend temperature then
re-t the Hub in the 6 o’clock position so that the Center
Stop Slot ts over the Cartridge Stop, locking rotation
in either direction.
Factory pre-set outlet temperature = 110°F (43°C)
Open the hot and cold water supplies and open outlets
prior to adjusting the temperature.
Rotate the spindle to adjust the temperature to a desired
level.
Clockwise = Decrease temperature.
Anti-clockwise = Increase temperature.
Keep the spindle undisturbed.
Obtain the desired maximum blend temperature then
re-t the Hub in the 9 o’clock position so the Hub Stop
hits the Cartridge Stop, preventing further anti-clockwise
rotation.
This sets the desired temperature as maximum
achievable temperature.
Commissioning
For Locked temperature For Adjustable temperature
3 mm

13
Step 4
Operation
Re-t the Knob, tighten the screw and replace the
concealing cap.
Make sure the indicator is in either the 9 o’ clock
position (adjustable temperature conguration) or 6
o’ clock position (locked temperature conguration).
*Maximum temperature stop or single temperature locking feature is established during the on-site commissioning
protocol .
For models with a standard temperature knob tted, adjustment of the blend temperature from preset maximum to
cold is achieved by clockwise rotation of the knob.
2. Constant Temperature
1. Adjustable Temperature
Counterclockwise
Hotter
(to Maximium
Temperature Stop*)
Clockwise
Cooler
Single Temperature
Locked*
(No Movement)
Exercising the Thermostat
Thermostatic mixing valves with thermostats are inclined
to lose their responsiveness if not used. Valves which
have been in storage, installed but not commissioned,
or simply not used for some time should be exercised
before setting the maximum temperature or carrying out
any tests. A simple way to provide this exercise is:
1. Ensure that the hot and cold water are available at
the valve inlets, and the outlet is open.
2. Move the temperature control rapidly from cold to hot
and hot back to cold several times, pausing at each
extreme.
3 mm

14
Warning! Isolate water supply to Model 320 before proceeding.
Model 320 Thermostatic Mixing Valves and its components should be inspected annually, or more frequently where
acknowledged site conditions such as high mineral content water dictate.
Model 320 Thermostatic Mixing Valve is of a sealed single “cartridge construction”. The cartridge can be removed
from the valve for inspection or replacement. To access the valves internal components for inspection, cleaning or
replacement proceed as follows.
Maintenance must be carried out in accordance with these instructions, and must be conducted by designated,
qualied 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 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.
Components are precision-made, so care must be taken while servicing to avoid damage.
Lubricant
Important! All seals are pre-lubricated. If you need to further 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.
Servicing & Maintenance
Maintenance Procedure - Cartridge Assembly
Isolate the water supplies to the mixing valve. Open an outlet tting to release pressure and to assist the draining
of residual water.
Step 1
3 mm

15
Step 2
Disassembly
1. Unscrew the knob using a 3mm Allen Key.
2. Remove the Knob and Hub.
3. Remove Temperature Indicator Trim.
4. Remove the cartridge assembly by rst removing the six phillips head-retaining screws and then smoothly
drawing the cartridge out. Do not twist or apply “side load” leverage when extracting the cartridge.
5. When installing a new or reinstalling an existing cartridge note the raised “H” on the hot inlet of the cartridge
and align to hot supply accordingly. Conversly, align raised “C” with cold supply.
‘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

16
Cleaning/Renewal of Parts
1. Internal parts (with the exception of the Thermostat Assembly) can be cleaned using a mild proprietary inhibited
scale solvent e.g. domestic kettle descalent. After descaling, always rinse parts thoroughly in clean water
before retting.
Note! The body interior must be cleaned carefully and not damaged in any way. Do not use any abrasive
material.
2. Examine all accessible seals for signs of deformation or damage, and renew as necessary, taking care not to
damage the seal grooves.
3. Lightly smear all seals and threads with a silicone-only based lubricant to assist re-assembling.
4. Inspect the thermostat assembly for signs of damage.
Note! This component cannot be tested individually, its service condition should be assessed as part of the
performance check; refer to Commissioning Checks.
5. Examine the Cartridge Assembly for signs of damage or corrosion; renew as necessary.
Re-assembly
1. Install a new or an existing cartridge. Align the marked “H” on the hot inlet of the cartridge to hot supply and
“C” on the cold inlet of the cartridge to cold supply.
2. Re-t the Cartridge Assembly and secure in position with the six phillips head-retaining screws.
3. Re-t Temperature Indicator Trim.
4. Before tting the hub, the temperature will need resetting; refer to COMMISSIONING.
5. Re-t the Hub and Knob.
6. Tighten the screw using a 3mm Allen Key.

17
Model 320 Spare Parts
D33388
D90916
D58389
D90919
D90917
D33385
D33390
X4
X3
Part No: Description Note
A D33385 Hub Pack
B D33390 Knob Pack
C D58389 Cartridge Assembly
D D90916 Seal Pack
E D33388 Screw Pack
F D90917 Indicator Trim
G D90918 3/4” Check Valve Service Pack - 1 Pair
H D80012 3/4” Male NPT Connector Pack Includes (2) inlet connectors complete with
checkvalves, one outlet connector, one outlet plug
I D90919 3/4” Female NPT Connector Pack Includes (2) inlet female connectors with no
checkvalves, one outlet female connector, one
outlet plug

18
Troubleshooting
Fault Diagnosis
Read the section “Important Safety Information” rst.
If any maintenance is required then it must be carried out by a competent tradesperson. Before replacing any parts
make sure that the underlying cause of the malfunction has been resolved.
Warning! There are no user serviceable components beneath the casing of the appliance. Only a competent
tradesperson should remove the cover.
Symptoms Probable Cause Possible Remedy
1. Only hot or cold water from
outlet.
a. Inlet supplies reversed (i.e.: hot to cold
or vice-versa)
Check-Rectify. Tip: Check rear of valve
under polymer mounting plate for
raised “H” (hot) on appropriate inlet. If
sight evaluation is not possible consult
factory Technical Support for additional
diagnositc tips.
b. No hot water available from hot water
source.
Check-Rectify
c. Screen/lters occluded or inlet supply
ttings plugged.
Refer to Servicing/Maintenance - Rectify.
d. Refer to Symptom 4 below. Refer to Symptom 4 below.
e. Proportioning mechanism (Cartridge)
trapped against hot/cold seat.
Refer to Servicing/Maintenance.
2. No ow from Mixing Valve
outlet.
a. Hot or Cold inlet supply failure;
Thermostat holding correct shutdown
function.
Check-Rectify.
b. Screens/lters blocked or inlet supply
ttings plugged.
Refer to Servicing/Maintenance - Rectify.
3. Mixed water temperature
at TMV outlet uctuates
and does not respond to
adjustment.
a. Thermostat not operating correctly. Replace Cartridge.
b. Mixing Valve operating below minimum
required ow rate.
Check that at least 2 GPM is owing
through valve.
c. Static inlet supply pressures beyond
valves capability to correct.
Check-Rectify
d. Inlet supply pressures fluctuating
beyond valves capability to correct.
Check-Rectify
e. Hot water supply temperature
uctuating beyond valves capability
to correct.
Check by carefully sensing inlet hot
supply pipe work- rectify.
f. Partially occluded screens/lters or
partially blocked inlet ttings.
Refer to Servicing/Maintenance - Rectify.
4. Hot water in cold supply
and vice-versa.
a. Indicates non-functioning check valve
(s).
Diagnose by turning off mixed water
outlet ow and check to see if inlet hot
pipe work becomes cold and vice-
versa.
(contd...)

19
5. Mixed water
temperature too high.
a. Mixing Valve set too high and has not
been commissioned correctly.
Refer to Commissioning - Rectify.
b.Mixing Valve has not been
commissioned correctly and was set
when the hot supply temperature was
too low.
Refer to Commissioning - Rectify.
c. Hot water is migrating into cold supply. See Item 4 above.
d. Thermostat not operating correctly. Replace Cartridge.
6. Mixed water
temperature too low.
a. Mixing Valve set too low and has not
been commissioned correctly.
Refer to Commissioning - Rectify.
b. Hot water heat is not keeping up with
demand.
Check-Rectify.
7. Mixed water ow rate is
reduced.
a. Partially occluded inlet screens/lters
or partially blocked inlet ttings.
Refer to Servicing/Maintenance - Rectify.
b. Inlet supply pressure has fallen. Check-Rectify.
c. Accumulated pressure losses within
the system are too high.
Refer to a trained and appropriate
authority for system sizing assistance.
8. Water leaking from
valve body.
a. Seals worn or damaged. Obtain Seal Pack and renew all seals.

Armstrong Hot Water Group, Inc. (“Armstrong”) warrants to the original user of those products supplied by
it and used in the service and in the manner for which they are intended, that such products shall be free from
defects in material and workmanship for a period of one (1) year from the date of installation, but not longer than
15 months from the date of shipment from the factory [unless a Special Warranty Period applies, as listed below].
This warranty does not extend to any product that has been subject to misuse, neglect, or alteration after shipment
from the Armstrong factory. Except as may be expressly provided in a written agreement between Armstrong and
the user, which is signed by both parties, Armstrong DOES NOT MAKE ANY OTHER REPRESENTATIONS
OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY
OF MERCHANTABILITY OR ANY IMPLIED WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE. The
sole and exclusive remedy with respect to the above limited warranty or with respect to any other claim relating
to the products or to defects or any condition or use of the products supplied by Armstrong, however caused, and
whether such claim is based upon warranty, contract, negligence, strict liability, or any other basis or theory, is
limited to Armstrong’s repair or replacement of the part or product, excluding any labor or any other cost to remove
or install said part or product, or, at Armstrong’s option, to repayment of the purchase price. As a condition of
enforcing any rights or remedies relating to Armstrong products, notice of any warranty or other claim relating to the
products must be given in writing to Armstrong: (i) within 30 days of last day of the applicable warranty period, or
(ii) within 30 days of the date of the manifestation of the condition or occurrence giving rise to the claim, whichever
is earlier. IN NO EVENT SHALL ARMSTRONG BE LIABLE FOR SPECIAL, DIRECT, INDIRECT, INCIDENTAL
OR CONSEQUENTIAL DAMAGES, INCLUDING, BUT NOT LIMITED TO, LOSS OF USE OR PROFITS OR
INTERRUPTION OF BUSINESS. The Limited Warranty and Remedy terms herein apply notwithstanding any
contrary terms in any purchase order or form submitted or issued by any user, purchaser, or third party and all such
contrary terms shall be deemed rejected by Armstrong.
Designs, materials, weights and performance ratings are approximate and subject to change without notice.
Visit armstronginternational.com for up-to-date information.
1233168-AL2-B Kohler Mira Limited, October 2017
1233168-AL2-A
Model® 320
Printed in U.S.A. - 10/15
© 2012 Armstrong International, Inc.
Limited Warranty and Remedy