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In these hot water temperature control articles, we explain how to buy, install, adjust and inspect anti-scald equipment to prevent hot water burns. We explain what a mixing valve, tempering valve, or anti-scald valve is, where and why these valves are installed on hot water systems, and how they work.
This article series answers most questions about Heating System Boiler Controls on central heating systems to aid in troubleshooting, inspection, diagnosis, and repairs. Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
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- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
Guide to Mixing Valves and Anti Scald Valves on Heating Equipment & Plumbing Fixtures
Here we will describe and illustrate various types of automatic and manual mixing valves, anti-scald valves, or compensating valves.
Photo: a Sparco anti-scald valve or tempering valve installed at a hydronic heating boiler. Other texts refer to these safety controls as mixing valves or compensating valves or temperature compensating valves.
Anti-scald valves used with water heaters are also called tempering valves or mixing valves. An anti-scald valve mixes cold water in with the outgoing hot water (or regulates pressure, or uses another approach) to assure that hot water exiting a building fixture is at a temperature low enough to be safe.
In the sketch shown below, courtesy of Carson Dunlop Associates, an anti-scald valve (also referred to as a tempering valve , a compensating valve or an automatic mixing valve) is shown installed at the hot water piping and tankless coil on a heating boiler.
The drawing illustrates that hot water leaving the tankless coil has been heated to 180 °F. by the coil which is itself immersed in hot boiler water. The 180 degree F. water leaving the tankless coil is mixed with 55 °F. water inside the tempering valve. This produces outgoing hot water from the valve cooled down to 140 deg F.
In the U.S., most authorities consider hot water at or below 120 deg F to be safe from scalding. Some facilities limit water temperatures to 100 deg. F.
How Long Will an Anti-Scald Valve Last?
Anti-scald valves typically are warranted for just 12 months from the date of installation. Plumbers report a typical tempering valve life of five years. (Moley 2022)
Kitchen and bath faucets themselves have a typical life expectancy of 15-20 years.
Really? We're uncertain about how various plumbers or others have defined the service life of these plumbing components. For example, a bathtub faucet may begin to drip after 2-8 years but may need nothing more than replacement of a faucet washer: a part costing less than $1.00 U.S. and a job within the capacity of many homeowners and most handymen.
Some plumbing faucets and valves, such as models using a ceramic cartridge, may last the lifetime of the building even if the faucet's finish and trim do not last that long.
Watch out: ease of replacement of faucet parts and even the cost of replacement faucet cartridges varies enormously. A typical brass Moen 1200 one-handle kitchen or bathroom faucet cartridge like the one shown above costs about $30. U.S. but we were quoted over $100. when trying to buy a ceramic faucet cartridge for a Kohler-brand bath sink faucet.
Other Kohler faucet cartridges currently sell for around $18.
Definition of an anti scald valve or compensating valve - to avoid hot water burns
Anti-scald valves are used on heating and plumbing systems to avoid hot water burns at plumbing fixtures such as sinks, showers, and tubs.
An anti-scald or mixing valve mixes cold water with the outgoing hot water either automatically or manually to make sure that a person using the plumbing fixture won't be scalded.
Definition of anti-scald valve vs. mixing or tempering valve: manufacturers recommend point-of-use anti-scald protection
Watch out: different definitions of mixing valve, tempering valve, anti-scald valve: most likely because of a combination of product liability concerns and because the manufacturer of a mixing valve cannot control what other plumbing installation or operating details are followed at individual buildings, heating boiler manufacturers recommend point-of-use anti-scald protection.
and mixing valve manufacturers described here, all take care to refer to products like the Sparco control shown above and the Watts mixing valve shown on this page as a mixing valve or tempering valve. They are not promising that the device will prevent burns from scalding hot water.
In fact, manufacturers (Watts for example) typically add that point of use scald protection should be installed:
ASSE
standard 1016, 1069 or 1070 listed devices should be used at fixtures to prevent possible injury.
That advice means that besides mixing valves or tempering valves that are typically installed at the water heater or tankless coil, separate anti-scald protection devices are available for and should be installed at the point of use: sink, shower, or tub etc. Those sorts of anti-scald devices are also discussed in this article.
Above, in our photograph of a more traditional single-function heating boiler limit control, the limit switch is being used on a tankless coil, serving as an upper limit on the temperature to which the boiler is to heat its water. This temperature may and usually is well above 120°F and so is a scalding burn hazard.
Confusion About Names, Types & Features of Scald Protection Devices
Really? In my experience with plumbing and heating installers, home inspectors, and consumers, these terms: automatic compensation valve, mixing valve, tempering valve, anti-scald device, automatic pressure regulating valve, pressure balancing valve, pressure compensating valve are thrown about in a blizzard of usages that treat the words as synonyms.
In the course of inspecting several thousand buildings between 1976 and 2014, I have almost never found anti-scald devices at individual plumbing fixtures in private homes. The only water temperature control we typically find are mixing valves at the hot water source. Worse, sometimes there is no hot water scald protection at all.
When a heating boiler uses a tankless coil to produce domestic hot water, a third single-function control may be installed for that purpose. In our photo, a Honeywell limit control switch is being used to monitor hot water temperature at the tankless coil which is in turn mounted on a steam boiler of an older home in Portland, Maine.
You can see the black-handled mixing valve in the lower right of the photo above.
Cold water from the building is entering the tankless coil via the bottom pipe (green corrosion) and hot water, heated by the coil is leaving at the upper part of the tankless coil, where it turns downwards to enter the left side of the mixing valve.
Additional cold water is permitted to enter the bottom of the mixing valve, and tempered (non-scalding) hot water then leaves at the right side of the mixing valve in that photo,
and in the enlarged version of the same installation and given just above, you'll see that the temperature limit on the control is set to about 140 °F. Scalding!
Types of Anti-Scald Controls
Temperature control purposes
Avoid scalding burns
on someone using the plumbing appliance - generally by trying to prevent water temperature at the device from exceeding a safe limit either set by the manufacturer or adjusted by the installer or user.
Note that once a temperature limit or stop has been set, water temperature might still vary both above or below that setting, depending on the type of limiting device and on the causes of variation of water temperature entering the building or of hot water produced by and exiting the water heater itself.
Avoid or minimize variations in water temperature -
generally by monitoring water pressure, flow-rate, or temperature to avoid surges of hot or cold water.
Sanitation:
commercial applications such as a restaurant kitchen dishwasher must maintain an adequately high temperature to meet sanitation requirements.
Economy:
in some applications, avoiding unnecessarily high water temperatures is desirable or necessary for energy conservation and economic reasons.
Locations of Anti Scald or Temperature Control Valves: Define POS & POU
POS: Point of source:
these controls are installed at the water heater or at the heating boiler that uses a tankless coil, as a tempering or mixing valve using any of several methods to control outgoing water temperature to the entire building, detailed below.
POU: Point of use:
these hot water temperature controls are installed at or close to the point of use or individual plumbing fixture as we detail below.
Other:
Occasionally, elsewhere in the building, such as for an individual building floor or an entire apartment in a multi-occupancy building
Watch out: as you'll read here and in the article topics we have listed, various water temperature control devices have different purposes, and not all of them are designed to prevent scalding burns.
So it is important that you select the proper temperature control device and that it is installed where its manufacturer intends, and that it is adusted as required.
Sources of hot water scald burn risk at buildings without adequate anti-scald device protection
Watch out: Where no anti-scald valve is installed, the risk of a person being badly burned by hot water can be significant in buildings for a variety of reasons that we will explain here, including:
Setting the water temperature too high
at a tank type water heater
Use of tankless coils,
demand type water heaters, and even electric shower heads
Use of water use efficiency improvement devices such as low-flow shower heads.
When a low-flow-rate shower head is retrofitted to a home where no anti-scald valve or automatic compensation valve has been installed, even if the shower controls or tub controls have been manually adjusted to provide safe comfortable water temperature, the unexpected use of other appliances or plumbing fixtures in the building can cause the water temperature at the shower or tub to suddenly become scalding.
Just flushing a toilet or starting a washing machine can cause a sudden drop in the cold water pressure or flow, leading to scalding burns.
Automatic compensation valves
in new homes protect
against severe changes in
water temperature when
the pressure drops; but
these systems are only
required to be tested at
a flow rate of 2.5 gpm.
It
follows that when the new
1.75 gpm showerheads
have no matching automatic
compensation valve,
anyone in the shower
runs the risk of being
scalded when the pressure
abruptly changes. -Koeller [6]
Watch out: it can be confusing listening to plumbers, home inspectors, and building supply sales staff who toss around terms like "mixing valve", "tempering valve", and "pressure-balancing valve" a bit loosely, all referring to ways to avoid scalding burns at plumbing fixtures, but not all working the same way.
Watch out: every anti-scald device, mixing valve, temperature control device whose instructions we reviewed includes a collection of safety warnings that explain the limitations of the device and its vulnerability to improper installation, improper adjustment, or to external causes of water temperature variation that are outside the scope of the control.
The installation instructions for these devices are very specific about the temperature settings, periodic maintenance, and other adjustments that are required for safe, reliable use. Be sure you read and follow the instructions for the specific brand and model anti-scald or temperature control device you are installing.
Mixing Valve Safety Warnings
Watch out: read the installation instructions from the manufacturer of the product you are installing, both to make sure it's installed properly and thus will work as expected, and also so that you understand what to expect by way of hot water temperature control that the product handles.
WARNING: Thermostatic mixing valves are intended to increase the supply of hot water available from the coil. They are not intended to prevent a scald hazard.
Similarly, the Watts Regulator Company's instructions for the installation of the Series LF1170 & LFL 1170 Hot Water Temperature Control Valves includes this warning: [Bold font is our emphasis]
WARNING: FAILURE TO COMPLY WITH PROPER INSTALLATION AND
MAINTENANCE INSTRUCTIONS COULD CONTRIBUTE TO THE VALVE
FAILURE.
This Hot Water Master Tempering Valves cannot be used for tempering water temperature at fixtures. Severe bodily injury (i.e., scalding
or chilling) and/or death may result depending upon system water
pressure changes and/or supply water temperature changes.
ASSE
standard 1016, 1069 or 1070 listed devices should be used at fixtures to prevent possible injury.
These Hot Water Tempering Valves are designed to be installed at or near
the boiler or water heater. They are not designed to compensate for system pressure fluctuations and should not be used where ASSE standard
1016, 1069 or 1070 devices are required. These valves should never be
used to provide “anti-scald” or “anti-chill” service.
The components of the system must be of materials with a construction
capable of withstanding the high limit output temperatures of the water
heating source. - Watts (2013)
Question: repair parts for Danfoss Mixing Valve
I am looking for repair kit for this Danfoss TMV mixing value or O-rings for use in my building in Nova Scotia, Canada - Anonymous by private email, 2017/04/03
Reply:
I can see why you asked, Anon, as it's difficult to find repair parts for Danfoss TMVs in Nova Scotia.
The first document below lists the components and parts of the mixing valve you describe - or a model close to it. The second provides instructions for a newer Thermostatic Mixing Valve or TMV from Danfoss, the Series 30 HR/HV.
Danfoss does not sell directly to the public. To buy Danfoss equipment or repair parts, check with your local plumbing and heating supplier or with one of the online Danfoss TMV repair part kit suppliers we'll list below.
Links to Danfoss mixing valve installation guides are given below.
Anti-Scald Valve Installation Manuals
Products listed here include thermostatic mixing valves of several types including valves that are installed at the fixture or point of use (POU thermostatic mixing valves), valves that are installed at the water heating source, and other products.
Watch out: as you will read in the individual product specifications, some thermostatic mixing valve instructions take care to mention that the valve does NOT provide scald protection and should not be used where ASSE 1070 devices are required.
A.O. Smith water heater safety sticker: 182734-000 Rev.00 observed on the gas fired water heater shown
Apollo DUAL PURPOSE THERMOSTATIC MIXING VALVE IO MANUAL [PDF] Model MVB & MVBLF ASSE 1017 Point-of-source & ASSE 1017 Point-of-use, Conbraco Industries Inc., 1418 Pearl St., Pageland SC 29728 USA Tel: 704-841-6000
These valves can support either point of source OR point of use hot water temperature control and anti-scalding.
Excerpt: The Apollo “MVB” Series are designed to mix and regulate the amount of cold and hot water to produce a comfortable and safe outlet temperature at a predetermined setting, either from the “point of source” or “point of use” application for single or multiple fixtures.
"BDS Series Oil-Fired Hot Water Boilers, Installation Instructions, Models GS-080 - Crown BDS-236", Crown Boiler Company, BDS 12-99, Crown Boiler Co.
P.O. Box 14818
3633 I Street
Philadelphia, PA 19134
(215) 535-8900,
Website: http://www.crownboiler.com, retrieved 2/26/2014, original source: http://www.crownboiler.com/manuals/content/ All_Models/BDS Series all models 9.pdf
The following link provides access to literature or manuals for previous Crown products:
http://www.crownboiler.com/Support/Manuals-And-Literature/Previous-Products
Excerpt: ASSE 1017 model 5231 series high flow thermostatic mixing valves are designed to be installed at the hot water heater (point of distribution) and cannot be used for tempering water temperature at fixtures as a point-of- use valve.
They are not designed to provide scald protection and should not be used where ASSE 1070 devices are required.
Series 5231 thermostatic mixing valves can also be used for regulating the flow temperature in radiant panel heating systems, to which it assures a constant and accurate control with ease of installation.
Cash Acme HEATGUARD 110-D SERIES TEMPERATURE-ACTUATED MIXING VALVE [PDF] (2014) assists in scald prevention, Cash Acme Corp., 2400 7th Avenue S.W. · Cullman · Alabama 35055 · USA · www.cashacme.com
US Contact: 1-877-700-4242 ·sales@cashacme.com ·Canadian Contact: 1-888-820-0120 · canadasales@rwc.com
ASSE compliance: ASSE 1017, ASSE 1069, ASSE 1070
CSA compliance: CSA B 125.3
Excerpt: The Heatguard®
110-D is a Temperature Actuated Mixing Valve that mixes hot water with cold
to deliver tempered water at a controlled temperature to 120°F (49°C) maximum.
The
Heatguard®
110-D is designed to assist in the prevention of scalding.
The Heatguard®
110-D is intended for installation at the water heater to distribute controlled
temperature water through the domestic hot water system or at point-of-use applications.
The
valve delivers water at a maximum of 120°F (49°C), allowing the heater to be set at 140°F
(60°C) or higher, thus providing a greater effective volume of hot water and reducing the
chances of Legionella bacteria growth in the water.
Radwell International, Tel: 800-884-5500 or International orders: +1 609 288 9393 or in the E.U., Tel: +44 1782 576800
Website: http://www.radwell.com/Buy/DANFOSS/082F8997
TMV repair kit for Danfoss 1" valve. (Radwell is not an authorized Danfoss distributor).
Danfoss Canada: Website: http://drives.danfoss.us/danfoss-drives/contacts-canada-sales/#/ - "Danfoss Drives" NOT for plumbing and heating controls
Photo: a replacement Delta Scald Guard cartridge. This is a rotational stop device. Detailed instructions on how to adjust this Delta scald guard device are given just below as a PDF download from the company.
Excerpt: THIS VALVE MEETS OR EXCEEDS THE
FOLLOWING STANDARDS: ASME A112.18.1/
CSA B125.1 and ASSE 1016 (Type -P- or -T-).
CAUTION:
This system/device must be set by the
installer to ensure safe, maximum temperature.
Any change in the setting may raise the discharge
temperature above the limit considered safe and
may lead to hot water burns.
NOTICE TO INSTALLER: CAUTION!
As the
installer of this valve, it is your responsibility
to properly INSTALL and ADJUST this valve
per the instructions given.
This valve does
not automatically adjust for inlet temperature
changes, therefore, someone must make the
necessary Rotational Limit Stop adjustments
at the time of installation and further adjustments
may be necessary due to seasonal water
temperature change.
YOU MUST inform the
owner/user of this requirement by following
the instructions.
If you or the owner/user are
unsure how to properly make these adjustments
please refer to page 7 and if still uncertain, call
us at 1-800-345-DELTA
If the water temperature is above 120°F,
remove the temperature control knob (1)
and rotate the limit stop (2) clockwise one
tooth for every 4°F - 6°F (approximate)
change in temperature. If water temperature
is cooler than desired, rotate the limit stop
counterclockwise.
IMPORTANT:
The first position of the
Rotational Limit Stop (the Limiter) is that
position that restricts the rotation of the
stem the most and is at the maximum
clockwise setting.
According to industry
standards, the maximum allowable
temperature of the water exiting from the
valve is 120°F.
This temperature may vary
in your local area.
The Rotational Limit Stop
may need to be readjusted if the inlet water
temperature changes.
For instance, during
the winter, the cold water temperature is
colder than it is during the summer which
could result in varying outlet temperatures.
Typical temperature for a comfortable bath
or shower is between 90°
–110°
F.
Potential scald or thermal shock injury could result due to cross flow if outlet at the
shower is blocked or restricted (e.g., pause control on showerhead).
Be sure to point
showerhead away from you when re-starting flow or install inlet check valves on both
supply lines to prevent possible injury
HONEYWELL (Sparco) AMX Series DirectConnect MANUAL [PDF] (2010) Honeywell International Inc.
1985 Douglas Drive North
Golden Valley, MN 55422
Honeywell Limited-Honeywell Limitée
35 Dynamic Drive
Toronto, Ontario M1V 4Z9
customer.honeywell.com
ASSE compliance: ASSE 1017 - requires installation of a check valve. An expansion tank must be installed with the check valve to accomodate thermal expansion.
Application:
Any application requiring accurate control of water
temperature based on mixing of hot and cold water, ...
Excerpt: The AMX300 Series DirectConnect™ Mixing Valves fit any application requiring accurate control of water temperature by mixing hot and cold water such as domestic water.
The valves are designed for mounting directly onto the water heater in residences, hotels, schools, hospitals, or nursing homes.
This valve meets or exceeds ASME A112.18.1/CSA B125.1 and ASSE
1016/ASME A112.18.1016/CSA B125.16.
WARNING: Risk of scalding. High water temperature can
cause severe burns.
Set the water temperature at or below
120°F (49°C) following the adjustment procedure.
WARNING: Risk of scalding or other severe injury.
Before
completing installation, the installer must set the maximum
water temperature setting of this valve to minimize the risks
associated with scalding hazards according to ASTM F 444.
CAUTION: Risk of personal injury. If the water
temperature is set too high, scalding will occur. The water
temperature should never be set above 120°F (49°C).
CAUTION: Risk of scalding. This device has been calibrated
at the factory to ensure a safe maximum water temperature.
Any variance in settings or water inlet conditions from those
used during factory calibration may raise the discharge
Moley, Hot Water Tempering Valve, Maintaining & Servicing, [Website] Moley Plumbing & Gasfitting, retrieved 2022/06/12, original source: https://www.moyleplumbing.com.au/blog/hot-water-tempering-valve-maintenance-service#:~:text=A tempering valve should last approximately five (5) years.
Excerpt:
HOW LONG DOES A TEMPERING VALVE LAST FOR?
A tempering valve should last approximately five (5) years.
We have replaced them earlier & later than this.
A tempering valve has a warranty of 12 months.
Excerpt: The Tempera (TRB-2) Pressure Balancing Valve is a piston-actuated valve.
It is necessary to Flush all supply
lines leading to the valve prior to installation.
We require only Teflon tape to be used when connecting this valve to the water system. The use of pipe dope or
liquid thread sealant will affect the proper operation of this valve and void the warranty.
Install the TRB-2 valve in line with the shower control valve. It is not necessary to install the TRB-2 valve close to
the shower control valve, as long as discharge lines are dedicated.
Install the TRB-2 valve with the flow arrows in
the proper direction with respect to flow. It is not necessary to maintain any particular geometric position for this
valve.
We require the installation of check valves (not included) on the inlet side of this valve to prevent potential cross
connection.
The TRB-2 valve is a mechanical device, which may require maintenance. Remember to place this valve
in an accessible location. Failure to follow these instructions will void any product warranty.
Excerpt: TempControl thermostatic mixing valve made from lead
free** metal components. Models 102-700 feature
serviceable integral check stops. Models 900 & 1000
feature removable check stops with union ells (see table 1
for flow rates).
TempControl Location vs water pressure fluctuations
An underlying premise of thermostatic water controller
installations is an acknowledgement that thermostatic
mixing valves will not operate properly when the hot
and cold supplies serving such valves are subjected
to pressure disturbances when flowing less than full
capacity.
In a correctly designed mechanical room, the
supply pressures are stable and not subject to pressure
disturbances.
As a result, when a TempControl valve is
indicated as being located in the mechanical room, a
Hi-Low system will not be recommended.
When the valve’s location is indicated as being outside
of the mechanical room, it is assumed that there is
a potential for pressure fluctuations in the hot and
cold supply lines servicing a TempControl valve and a
Hi-Low system will automatically be recommended.
Excerpt: Water temperature limiting valve including integral
checks and dual stainless steel strainers for double
protection against suspended particles in supply
lines.
Valve made from lead free metal components
(see table 1 for flow rates).
Temperature control range:
60°F - 140°F (15.6°C - 60°C) Water Temperature Limiting Valve Cartridge Replacement
1) Shut off hot and cold water supplies to valve.
2) Remove safety cap by inserting a small
screwdriver into the widest opening at the base
of the cap and pry upward. This will expose the
cartridge stem and cartridge retaining unit.
3) Remove retaining nut by turning counter-clockwise
with adjustable wrench.
Grasp cartridge with
pliers and remove from body by pulling straight
out.
A slight rocking rotation may be required to
loosen while removing.
4) Lubricate cartridge o-rings with a small amount of
lubricant prior to reinstalling. Insert replacement
cartridge into valve body, applying enough force to
ensure cartridge is fully seated.
Install cartridge
with keyway inline with Symmons logo located on front of valve casting as shown below to the
left. Install retaining nut back onto valve body.
[Note the requirement t torque the retaining nut to 132 inch pounds. - Ed.]
5) Refer to "Setting Valve Temperature" section (pg.4)
to properly set valve to desired temperature.
Seasonal Use
If valve is used seasonally, such as in schools or
campgrounds, then perform the following steps to
avoid damage caused by freezing water when valves
are not in use:
1) Shut off hot and cold water supplies.
2) Remove valve cartridge and drain all water.
3) Drain water from the supply lines and valve body.
Service Instructions
Cleaning or replacing filter washer and check valve:
1) Remove union adapter nut from valve body and
then valve fitting from union adapter.
2) Clean filter washer seated in valve fitting by
soaking both in household vinegar and rinse under
running water. Ensure not to damage screen in
filter washer.
3) Replace filter washer into center of valve fitting.
4) Replace check valve by removing from center of
valve body port connection.
5) Fasten and tighten union adapter nut over valve
fitting to valve body.
Excerpt: The Taco Series 5000-3 Mixing Valve is supplied factory set at 105-115°F with 150°F hot water inlet temperature. It may need to be altered depending on operating requirements
In the instructions see "Setting the Temperature Limit Stop" for details on how to control and regulate water temperature.
Excerpt: The pressure balancing cartridge contained in this valve
compensates for pressure fluctuations in the water
supply system through a diaphragm-connected pressure
balancing mechanism.
The outlet temperature will change
by no more than a mere ±2°F (1°C) with a 50% drop in
either the hot or cold water pressure.
Even if the cold
water pressure fails completely, the anti-scald design will
reduce the flow rate to a safe level ensuring reliable
protection against scalding.
The built-in check valves
prevent cross flow between the hot and cold supplies.
WATTS MINIMIXing POINT OF USE THERMOSTATIC MIXING VALVE IO MANUAL [PDF] (2018) sold and used in the the EU and UK, WATTS INDUSTRIES France
1590 avenue d’Orange, SORGUES 84275 VEDENE, FRANCE Tel. +33 (0)4 90 33 28 28 • Fax +33 (0)4 90 33 28 29/39
Email: contact@wattswater.com Web: www.wattswater.fr
ASSE compliance: not stated
UK / EU anti-scald compliance: try www.wattswater.eu
ASSE compliance: not explicitly stated although the document shows an ASE1069 application in an illustration
and it
includes logos/insignia from ASSE and UPC and a an ATA logo "Advanced Thermal Activation"
Above: The Watts LF1170-M2 hot water mixing valve used for either domestic hot water temperature control or in radiant heating system temperature control systems.
Above: Watts illustration (edited by IAP) showing how the LF1170 or LFL1170 mixing valve is "trapped" 8 to 12 inches below the hot water outlet from the water heaterr when used to provide tempered domestic hot water (washing & bathing).
IMPORTANT: To prolong life of the Model 1170-M2, L1170-M2, LF1170-M2 or LFL1170-M2 valve, it is recommended that it be trapped as shown: i.e. the hot water inlet to the 1170-M2 or LF1170-M2 should be 8" - 12" (200 - 306mm)
Below: Watts illustration (edited by IAP) showing how the LF1170 or LFL1170 is plumbed when used to control temperatures in a radiant heat system.
Approval: CSA B125 Certified
ASSE compliance: ASSE 1016, ASSE 1017 & ASSE 1070
Flow rates certiified for this valve and listed in this document are: When tested in accordance with ASSE 1016, ASSE 1017 & ASSE 1070.
ISO 9001 certified.
Inspection of Mixing Valves or Anti-Scald or Tempering Valves
This discussion has been moved to a separate article now found
Point of Use Anti-Scald Valves,
Guide to Bath Fixture Anti-Scald Valves, Automatic, Thermostatic Mixing Valves, or Tempering Valves to Avoid Hot Water Burns
On 2019-11-21 (mod) - water not hot enough after installing a mixing valve
Jac
I can but guess because there is other information about your plumbing system that I don't know, but it's possible that you are anti scald device is installed at the water heater and that there is too much distance between that point and the nearest hot water Plumbing fixture.
In that case you're regulating the water temperature at the source but the water continues to cool off on the way to your tab.
A solution would be to install the anti scald device right at your plumbing fixtures. It's more expensive in the landlord may not want to do that. OR the mixing valve output temperature is simply set lower than necessary. Temperature can be set as high as 120F. but no higher at the fixture or there'd be a scalding burn hazard.
On 2019-11-21 by Jacquie
A mixing or equalizer valve was just installed on my hit water tank by the landlord. I am finding that the water isn't hot enough for us. We were told the temperature would be set for 110°F and would not be allowed to be higher.
We also pay for our own hot water usage through the gas company and it isn't being paid for by the landlord. We are not using any cold water for showers or for anything other than drinking at this point. I would like to know if there is a way to increase the amount of hot water.
There is no risk of scalding in this house as we are adults who know how to live responsibly while using the water without harm to ourselves and others within the home.
On 2019-11-17 - by (mod) -
How do I adjust my GE boiler water temperature
Moh
If we are talking about a domestic water heater that produces hot water for washing and bathing, there will be a thermostat (or two of them) on the water heater; the thermostat controls vary depending on whether the heater is fueled by oil or gas or electricity.
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In addition to any citations in the article above, a full list is available on request.
Thanks to Bruce Jones, Renewable Energy Solutions Manager, for suggesting clarifications about which way to turn the mixing valve to make water supply hotter or colder. email August 2010.
Thanks to reader J.S.A. for discussing hot water mixing valves and which way to turn the valve - July 2010
Thanks to reader Athena for discussing hot water mixing valves and which way to turn the valve to make water hotter or cooler - October 2010.
Thanks to reader Chris Martino for pointing out inconsistent text about which way to turn the hot water mixing valve or tempering valve. December 2010.
Thanks to reader Bob for discussing clarifications needed to text about which way to turn the hot water mixing valve. January 2011.
[5] "Water Saving Tips: For Residential Water Use, Indoors and Out" Alliance for Water Efficiency, 300 W Adams Street, Suite 601 Chicago, Illinois 60606, Tel: 773-360-5100, 866-730-A4WE, Email: jeffrey@a4we.org, web search 12/14/11, original source: plumbingefficiencyresearchcoalition.org
[6] "Danger in the Shower: 2008 Forum Looks at Hot Water", John Koeller, Home Energy, Jan/Feb 2009, Home Energy Magazine, 1250 Addison Street Suite 211B, Berkeley, Ca. 94702, Tel: (510) 524-5405 Email: contact@homeenergy.org
In addition to citations & references found in this article, see the research citations given at the end of the related articles found at our suggested
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
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