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Here 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.

If your hot water temperatures are too low, see Temperature of Hot Water is Too Low
If you do not have enough hot water pressure or hot water quantity, see HOT WATER IMPROVEMENTS

This website 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.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Guide to Mixing Valves and Anti Scald Valves on Heating Equipment & Plumbing Fixtures

Definition of an anti scald valve or compensating valve used 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. We describe and illustrate various types of automatic and manual mixing valves, anti-scald valves, or compensating valves in this article.

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.

Approaches to controlling hot water temperature to avoid scalding burns

The high temperature limit control on the water heating device itself can be set to prevent scalding water from being produced. Below at Table of Scalding Temperatures & Times we include a photo of a typical water heater label warning about scalding temperatures, implying that this option is one to consider.

A point of supply pressure balancing valve or automatic mixing valve (compensating valve, or a manual mixing valve) can be installed at or near the water heater, or at the tankless coil or other hot water source so that scald protection is provided even if the water heater is set to a high temperature. This approach is sometimes used to obtain more total hot water as we discuss at Mix Valve Improves Hot Water Quantity and detail at HOT WATER IMPROVEMENT.

This approach is discussed beginning at How Anti Scald Valves Work, and further reviewed by Steven Bliss at Water Pressure-Balancing Valves.

An temperature-sensing thermostatic mixing valve or anti-scald device can be installed at or near the water heating device so that even if the water heater is set to a high temperature (to obtain more total hot water as we discuss at Mix Valve Improves Hot Water Quantity and detail at HOT WATER IMPROVEMENT).

This approach is illustrated and explained at Built-in Fixture Anti-Scald Valves and is discussed further by Mr. Bliss at Thermostatic Mixing Valves.

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 this photo.

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 this photo.

In this picture of a more traditional single-function heating boiler limit control, the limit switch is being used on a tankless coil, and in the enlarged version of the photo you'll see that the temperature limit on the control is set to about 140 degF.

Below we show a sketch that explains how an anti-scald valve or tempering valve actually works.

Tables of Scalding Temperatures & Exposure Times that Cause Hot Water Burns, Laws, Regulations.

See Table of Scalding Temperatures & Times for a table of safe temperatures for residential hot water.

See Hot Water Anti-Scald Regulations for a table of Hot Water Anti-Scald Limits, Hot Water Anti-Scald Laws & Hot Water Regulations

How Automatic Anti Scald Valves, Mixing Valves, or Tempering Valves on Water Heaters Work

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 to assure that hot water reaching a building fixture is at a temperature low enough to be safe. In the sketch shown at left, courtesy of Carson Dunlop, 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 degF. by the coil which is itself immersed in hot boiler water.

The 180 deg .F. water leaving the tankless coil is mixed with 55 degF. 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.

Automatic vs. Manual Mixing Valves Work Differently and are Not Equally Safe

An automatic mixing valve or compensating valve such as those sold by Watts Regulator Co. or Sparco (and illustrated below) includes a temperature sensing mechanism that automatically adjusts the amount of cold mixed in with outgoing hot water to maintain the desired output water temperature.

A manual mixing valve such as those often installed at older tankless coil hot water systems uses a simple gate valve that is manually adjusted by the homeowner.

At a minimum the homeowner may have to adjust this valve seasonally depending on whether or not the building is also being heated by the same boiler as during the heating season the boiler will be kept hotter than during the rest of the year, making the outgoing hot water too hot.

Guide to Installing & Setting Automatic Anti-Scald Tempering or Mixing Valves at a Tankless Coil - Water Pressure Balancing Type

Which Way do We Turn the Anti-Scald or Automatic Mixing Valve to Make Hot Water Cooler or Hotter?

Question about tankless coil or other hot water mixing valve operation - example using the Sparco Aquamix AM 102C:

I'm not sure which way to turn my hot water mixing valve. When you turn "down" on valve does it send less cold water or more. I believe it's less. Let me know. - J.S.A.

Answer:

There should be a direction arrow on the anti-scald valve telling you what it is doing and which turn direction will raise or lower the outgoing water temperature.

The Sparco Aquamix AM 102C tempering valve shown (above-left) is marked to explain that if we turn this valve counterclockwise (the direction of the red arrow) the outgoing water temperature will be hotter.

Turn this anti-scald valve (and most model) clockwise (in the direction of the blue arrow) to make the outgoing water temperature cooler.

Our photo of a Sparco™ Aquamix AM102C anti-scald or tempering valve (above-left) as well as our photo of a Watts™ mixing valve shown earlier in this article both show the arrow that we describe and indicates that turning the automatic mixing valve knob clockwise makes the outgoing water cooler, and turning the automatic mixing counterclockwise makes the outgoing water hotter.

We don't describe the valve direction as "up" or "down" because these valves can be installed in more than one position, making "up" and "down" a bit confusing.

For hotter output water [on the Sparco or Watts Tempering Valve models shown]: Turn the automatic mixing valve knob counter-clockwise (on the Sparco valve above, in the direction of the red arrow) to make the output water from the system hotter.

For cooler output water: Turn the automatic mixing valve clockwise (on the Sparco valve above, in the direction of the blue arrow) to mix in more cold water and thus to make the output water from the system cooler.

Note that because these mixing valves are automatic, that is once they have been set they maintain a specified hot water temperature for water leaving the water heater, you don't have to make seasonal changes to the valve adjustment.

The automatic mixing valve, tempering valve, or anti-scald valve approach of installing this safety control at or close to the water heater is discussed further at Thermostatic Mixing Valves.

Watch out: Be sure to take a close look at the indicating arrows on your own automatic mixing valve as some tempering valve models may work differently. And for manual hot water mixing valves that we discuss below, the direction to turn the valve may not be marked, but is easy to determine, as we will explain.

Thanks to readers Bruce Jones and Chris Martino and others for pointing out the need for clarity about about which way to turn the hot water mixing valve or tempering valve.

If your automatic tempering or hot water mixing valve has different instructions or operates differently from those discussed here, CONTACT us and send along a photo so that we can add that information here.

Guide to Using a Manual Hot Water Tempering Valve on the Domestic Hot Water Supply

By manual hot water tempering valve we mean that the plumber has installed an ordinary plumbing valve and a cold water bypass pipe to mix some cold water into the water heater's outgoing hot water supply.

This valve must be adjusted by the building occupant to obtain the desired temperature.

Our photo (left) shows a manual mixing valve (a gate valve) that is opened to add cold to outgoing hot from the tankless coils water heater. The valve in the center-right of the photo allows cold water to be added to the hot water leaving the coil. (The copper pipes were painted white - don't ask.)

A manual tempering valve does not respond to changing conditions on its own.

Which Way to Turn a Manual Anti-Scald Valve or non-Automatic Mixing Valve to Control Hot Water Temperature

By "manual" mixing valve we mean that an ordinary plumbing valve, usually a gate valve or ball valve is used to adjust outgoing hot water temperature, and the building occupants have to adjust the valve by hand, "manually". In most cases a manual hot water mixing or tempering valve (discussed below) will work oppositely from many models of the automatic tempering valves discussed above.

On a manual mixing valve or "tempering valve" if we "close" the manual valve by turning it clockwise we are are admitting less cold water into the mixing process, thus making the output water temperature hotter at plumbing fixtures in the building.

Here is a manual mixing valve on a hydronic heating system. You may find a ball-valve like this controlling domestic hot water temperature, radiant floor heating temperature, or even individual heating zone water temperature. This manually controlled valve (a human has to turn it) feeds some cold water into the hot water that is piped to building plumbing fixtures. So, for a manually operated tempering or mixing valve, Opening (turning counter-clockwise) a manual mixing valve mixes in more cold water and makes the resulting "hot water" in the building cooler - it lowers the temperature of the outgoing hot water. Closing (turning clockwise, or "in" or "down" or "closed") a manual mixing valve mixes in less cold water so it makes the resulting "hot water" in the building hotter - it raises the hot water temperature. When Should We Adjust a Manual Hot Water Tempering or Mixing Valve? Hot Water Made by a Tankless Coil & Heating Boiler - Manual Adjustment of Tempering Valve Watch out: if your hot water system uses a manual tempering valve and your hot water is made by a tankless coil and a hot water or steam heating boiler (as opposed to a separate hot water heater and tank), you will want to manually adjust the valve to produce a safe (below scalding temperature) hot water temperature measured at the plumbing fixture located closest to the hot water source (the heating boiler). During the heating season when the boiler is hotter, you'll want to adjust the valve again to prevent the hot water temperature from being too high. In sum, you'll need to change the manual mixing valve setting twice a year. At the end of the heating season, when the same heating boiler continues its job of making domestic hot water at a tankless coil or side-arm coil, you will need to adjust the manual tempering valve again to close off some of the mixed-in cold so that your water temperature is hot enough. That's because on most heating boilers using an aquastat or even separate individual boiler temperature controls, the boiler remains at a lower temperature when the building thermostats are never calling for heat. Hot Water Made by a Separate Water Heater Using a Manually-Adjusted Tempering Valve A second reason you may need to adjust the manual hot water mixing valve is that in some areas the temperature of the cold water entering the building may vary by season. Even if your hot water is made by a separate hot water heating tank, your system might have a manual mixing valve installed and you might need to adjust that setting seasonally as incoming water temperatures change. More information about tankless coils, how they work, what goes wrong, and their controls, is at TANKLESS COILS. See Water pipe clog repair guide for a discussion of loss of water pressure due to clogged piping or clogged tankless coils.

Guide to Bath Fixture Anti-Scald Valves, Thermostatic Mixing Valves, or Tempering Valves to Avoid Hot Water Burns

Anti-scald valves that actually sense the water temperature are available built right into bathroom sink or shower fixtures, as you can see in our photo at left. These devices permit delivery of very hot water to a building area but protect occupants from scalding by mixing in cold water right at the sink, tub, or shower. As you can see on the control shown in our photo of a shower control in a shower-bath in Molde, Norway, fixture anti-scald valves may include a button and adjustment that lets the user demand hotter water than the control provides automatically. On this bath shower fixture the left-hand control turns water on or off, and the right-hand control permits adjustment of the water temperature. Turning the temperature control "down" or counter-clockwise increases water temperature but the control "snaps" into a locked position at a safe hot water temperature of about 100 degF. The user can obtain hotter water by depressing a red button and turning the control further. The point-of-use anti scald protection afforded by this type of pressure-balancing anti-scald valve is discussed further at Water Pressure-Balancing Valves..

How Can an Anti-Scald Valve Improve the Hot Water Volume & Quantity?

Using an anti-scald valve or "mixing valve" or "tempering valve" on a hot water supply system can increase both the actual and the apparent total quantity of hot water available. That is, building occupants get a longer time in the shower, provided the hot water is used with some sense, as we explain here.

We will have more "heat" stored in the hot water tank (or more heat stored inside the heating boiler that in turn is going to heat a tankless coil and thus heat water passing through the coil) if we can keep the hot water tank (or boiler) at a higher temperature.

Watch out: when we heat the hot water tank or boiler to a higher temperature we also increase the chances of someone being scalded at the tap.

Therefore, to avoid scalding, we mix cold in with the outgoing hot water (the right way to do this).

Where a mixing valve is not installed (watch out for scalding!) we can be smarter at the plumbing fixture itself by turning on less hot water flow and more cold water flow so that the water is not scalding.

This combination of keeping water in the hot water tank (or boiler) hotter, but causing the volume of hot water to flow more slowly at the individual plumbing fixture, mixing in enough cold to get adequate flow quantity and safe temperature, is a risky (scald risk) alternative to using a mixing valve.

We don't recommend this alternative, (see MIX VALVE SCALD PROTECTION, Best Practices) but we explain it here as you may encounter this approach, especially in an older building and one where there are no small children nor elderly occupants (who are at greater risk of being scalded).

In either case, by starting with a hotter water heater or boiler and by mixing in cold in the outgoing water (or by regulating water pressures at the fixture), we consume hot water in the water heater tank more slowly. That means longer time in the shower.

In sum, with careful installation of appropriate safety controls such as an automatic mixing valve or automatic tempering valve (or by careful use of a manual mixing valve), we can heat water in the water heater storage tank or tankless coil to a higher temperature, mixing or tempering it as it leaves the water heater or at the point of use in the building to avoid scalding. The result is more total hot water available from the same water heating equipment.

Details about various ways to get more hot water or better hot water pressure and flow are at HOT WATER IMPROVEMENT where we provide a detailed guide to improving hot water quantity and flow when a tankless coil is installed as well as using other methods of hot water heating.

Watch out: setting water heater temperature higher to attempt to obtain more total hot water at the plumbing fixtures without also installing and properly setting anti-scald devices can result in dangerous, even fatal hot water scalding burns.

How do we Inspect Mixing Valves or Anti-Scald or Tempering Valves

Safety First: assure that the mixing valve has been set to protect the building occupants from scalding. Remember that while these valves may show a target temperature on the valve setting knob, the actual water temperature that comes out of a building faucet or tap will vary and may be hotter or cooler than the actual temperature set.

This is not precise lab-grade equipment capable of controlling water temperature precisely, and more, the length of pipe run between the hot water source and the building faucet or fixture will affect the temperature of water received there. A long run of un-insulated hot water pipe will deliver cooler water than a well-insulated water supply pipe of any length.

Leaks Second: See Tankless Coil Leaks for a detailed discussion of how to recognize, evaluate, and repair leaks at tankless coils on heating boilers

Best Practices Guide to Scald Protection for Bathrooms, Tubs, Showers

Our home page for anti scald devices used in plumbing systems is MIXING / ANTI-SCALD VALVES. The article below, MIX VALVE SCALD PROTECTION, Best Practices, includes excerpts or adaptations from Chapter 6 of Best Practices Guide to Residential Construction, courtesy of Wiley & Sons and written by Steven Bliss.

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.

There are several approaches to controlling hot water temperature to avoid scalding burns:

The high temperature limit control on the water heating device itself can be set to prevent scalding water from being produced. Below at Table of Scalding Temperatures & Times we include a photo of a typical water heater label warning about scalding temperatures, implying that this option is one to consider.

A point of supply pressure balancing valve or automatic mixing valve (or a manual mixing valve) can be installed at or near the water heater, or at the tankless coil or other hot water source so that scald protection is provided even if the water heater is set to a high temperature. This approach is sometimes used to obtain more total hot water as we discuss at Mix Valve Improves Hot Water Quantity and detail at HOT WATER IMPROVEMENT.

This approach is discussed beginning at How Anti Scald Valves Work, and further reviewed by Steven Bliss at Water Pressure-Balancing Valves.

An temperature-sensing thermostatic mixing valve or anti-scald device can be installed at or near the water heating device so that even if the water heater is set to a high temperature (to obtain more total hot water as we discuss at Mix Valve Improves Hot Water Quantity and detail at HOT WATER IMPROVEMENT).

This approach is illustrated and explained at Built-in Fixture Anti-Scald Valves and is discussed further by Mr. Bliss at Thermostatic Mixing Valves.

As noted in Chapter 6 of Best Practices Guide to Residential Construction:

There are many styles of mixer valves in tubs and showers, but all should have some sort of protection against scalding. The young and elderly are at greatest risk due to thinner skin and slower reaction times. More than 35,000 children, most under age six, are treated each year in emergency rooms for tap-water scald burns, according to the National Safe Kids Campaign.

A child exposed to 140°F water for as little as three seconds (see Table of Scalding Temperatures & Times) can sustain a third-degree burn requiring hospitalization and skin grafts. Although most scald burns occur in the kitchen, according to the Consumer Product Safety Commission, the most severe scald burns are caused by water flowing into the tub or shower. In response, many state and local codes now require antiscald protection in residential tubs and showers.

Many organizations advocate setting water heaters to no more than 120°F, which gives bathers significantly more time to move away or adjust the temperature before a burn occurs. While this strategy is helpful, it is not always reliable and can cause other problems:

Noncompliance: many homeowners turn the thermostats up to increase supply.

Water heater thermostats are often inaccurate. The ANSI standard for gas water heaters allows the temperature to vary by plus-or-minus 10°F.

Stacking effect: water at the top of a gas water heater can exceed the set point by as much as 30°F.

Use of Point of Supply Water Pressure-Balancing Valves to Control Temperature & Avoid Scalding

This is the most commonly used point-of-supply approach. These automatically adjust the water pressure to maintain the mix of hot and cold water to within 2°F to 3°F of where the user set the shower control.

If cold water is diverted to a flushing toilet or other appliance and the pressure drops, the valve automatically reduces the hot water flow proportionately to maintain the temperature.

If the cold water pressure plummets or stops altogether, the flow is reduced to a trickle.

To guard against someone accidentally turning the shower valve to scalding temperatures, these valves typically use a temperature limit stop that prevents the user from turning the shower control past a set point—typically set at or below 120°F.

Use of Point of Supply or Point of Use Thermostatic Mixing Valves to Avoid Scalding Burns

Some models of thermostatic mixing valves are more expensive than pressure-balancing valves and not widely used in the United States. They can be installed either inline near the water heater or as part of the shower control. The inline type of valve, also called a tempering valve, adds cold water to the hot water as it leaves the water heater to maintain a constant temperature, set by the installer. These are commonly used with solar water heaters but can also be tied to a conventional water heater.

A check valve is required on the cold water side to prevent backflow, and a hot-water expansion tank is recommended to prevent excessive pressure on the hot water side.

The other type of thermostatic valve is built into some high-end showers (Figure 6-54). These allow the user to set the temperature on a dial when showering. The unit will compensate for changes in either pressure or temperature to maintain a constant delivery temperature and flow rate. If the cold water fails or the tempered water is still too hot for any reason, the unit will shut off the flow. As with the pressure-balancing valve, the installer sets a temperature limit stop to prevent the user from turning the shower control to scalding temperatures. We illustrate this approach as it is installed in a modern bathroom in Molde, Norway at Built-in Fixture Anti-Scald Valves. [Click any image or table to see an enlarged version with additional detail, commentary & source citation.]

Retrofits to Avoid Scalding Burns at Plumbing Fixtures

In retrofits, point-of-use devices can be installed by a plumber or homeowner to limit water temperatures to 120°F. These include antiscald showerheads, as well as point-of-use devices that fit into individual plumbing fixtures, such as showerheads and bath and sink faucets.

For example, MemrySafe and ScaldShield (Antiscald Inc.) are inexpensive retrofit devices that reduce the water flow to less than 1/4 gallon per minute when the water temperature at the faucet or showerhead exceeds 120°F. These devices do not regulate temperature or pressure, but do offer protection against serious burns.

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MIXING / ANTI-SCALD VALVES
  Define Mixing Valves, Anti Scald Valves
  Table of Scalding Temperatures & Times
  Hot Water Anti-Scald Regulations
  How Anti Scald Valves Work
  Installing & Setting Anti-Scald Valves
  Which Way To Turn the Mixing Valve
  Using a Manual Hot Water Tempering Valve
  Built-in Fixture Anti-Scald Valves
  Mix Valve Improves Hot Water Quantity
  Inspect Anti-Scald Valves

MIX VALVE SCALD PROTECTION, Best Practices
  Water Pressure-Balancing Valves
  Thermostatic Mixing Valves
  Retrofits to Avoid Scalding Burns

• Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• A.O. Smith water heater safety sticker: 182734-000 Rev.00 observed on the gas fired water heater shown at High Efficiency Gas Water Heaters
• 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.
• "Domestic Hot Water Scald Burn Lawsuits, The Who, What, When, Why, Where, How", Dr. D. Bynum Jr., Vernon L. Petri, Esq., John T. Myers, paralegal, Seminar and Technical Paper for the 25-28 Oct 98 Annual ASPE Meeting at the Indianapolis Convention Center, Indianapolis IN, websearch 09/21/2010,original source: http://media.wattswater.com/F-H20LS-Reprint.pdf [Large PDF]
• [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

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

• Carbon Monoxide Gas Toxicity, exposure limits, poisoning symptoms, and inspecting buildings for CO hazards

• Fuel Oil & Oil Heating Magazine, 3621 Hill Rd., Parsippany, NJ 07054, 973-331-9545
• Inspection Procedures for Oil-Fired Heating Systems Detailed step by step approaches for inspecting complex systems]
• Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
• National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
• The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
• Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
• The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
• Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
• "Residential Steam Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• "Residential Hydronic (circulating hot water) Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• "Warm Air Heating Systems". Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
• Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
• Installation Guide for Residential Hydronic Heating Systems
• Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
• The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)

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