NOH_ASSE_ASPE-05-10

Tankless Water Heaters An overview of the advantages, opportunities and key design points of this emerging technology

Rheem Manufacturing Company is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credits earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-AIA members are available on request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials , methods, and services will be addressed at the conclusion of this presentation.

Copyright Materials This presentation is protected by US and International copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. Rheem Manufacturing Company 2008

Learning Objectives •

Understand the history and growth associated with tankless water heaters, and the forces behind this growth.

•

Understand the advantages of tankless water heaters, and recognize some of their possible shortcomings.

•

Understand that tankless water heaters are not standardized, and how this can play a significant role in design considerations.

•

Understand the basics of various installation options and industry accessories that can aid in that installation.

•

Understand the basic tankless system sizing concept and how it differs from current methods used to size tank hot water systems.

Now is the time for Tankless Water Heaters But first…….

Can you take a fresh look at things? I’m looking for a color. . …the color of a Yield sign.

Tankless Water Heaters History of Tankless Water Heaters • It started in the USA with – Edwin Ruud – In 1889 Edwin Rudd was awarded a patent for his design of a tankless water heater. It had a cast iron body with a copper heat exchanger, and his patent was on a gas actuator valve which turned on the burner when a water faucet was opened

• The American Desire for Storage Tanks – Sometime in the 1920’s the cast iron all copper heat exchanger design became to expensive to produce – During that period America was introduced to a galvanized steel tank and then glass lined tanks in the1940’s – And it’s been that way ever since…until now

Tankless Water Heaters Tankless Global Perspective Tankless technology – Tankless water heaters are used throughout most of the civilized world except in North America – Leading markets are Japan, China, Australia, Spain & Taiwan

World Market – – – – –

Total World Water Heater Market is $10.8 billion Gas tankless market is half or $5.4 billion Electric Storage is $3.2 billion Gas Storage is $1.7 billion Electric tankless is $500 million

Tankless Water Heaters US Market Today • 2009 Total US Market was 325,000 units – – – – – – – –

40% growth between 2003-2005 50% growth in 2004 alone 36% growth in 2006 30% growth in 2007 LP currently accounts for 1/3 of market Will become 10% or more of the gas market before 2015 Future impact estimated at 30-40% of market Australian Model: 0 to 30% of market in @7 years

Tankless Water Heaters

Why Tankless

Tankless Water Heaters Tankless Vs Tank at 90o Rise 40,000 Btu’s

199,900 Btu’s

151 lbs

55 lbs

.62 EF

13 Ft3

67 gal 1st hour (55 gal electric)

.82 EF

222 GPH

2 Ft3

Tankless Water Heaters Advanced Technology – Most Models • Self-modulating or staged burner provide maximum energy efficiency  Btu input automatically increases as demand for hot water increases

   

Only operates when there is a demand for hot water

• No standing pilot

– Electric spark ignition

• Temperature rise determines maximum output capacity ((HW outlet) – (CW inlet)) = Temperature rise

Tankless Water Heaters Why Tankless – Energy Efficient • Up to 15% compared to new 80% efficient commercial tank • Up to 30% compared to new residential tank units • Off unless there is a demand for hot water

– Environmentally Friendly • Low NOx on most

– Precise temperature control • Most high end models • 20 – 50 increments

– Digital displays • Temperature control • Diagnostics and maintenance codes

Tankless Water Heaters Why Tankless – Installation flexibility • Indoor, outdoor and direct vent models • Vent horizontally or vertically • Possible lower installed costs

– Space Saving • Install close to end-use • Smaller Footprint – easier to zone

– Unlimited supply of hot water • Primary residential benefit • Manifold up to 20 or more units

– System Redundancy in manifold • If one goes down, the others remain operational

Tankless Water Heaters

Tankless Water Heaters Are Not Standardized

Tankless Water Heaters Market Awareness – Know The Product • Compare units at same temperature rise – Not a 450F rise with a 350 rise – GAMA rates at 770 rise

• Know the minimum fuel pressure required – Varies from 4” to 6” w.c. natural – 8” to 10” w.c. propane

• Know clearance to combustibles – Varies from ½” to 6” or more on the sides – 0” to 2” in rear – Up to 36” to the top and 24” to the front

Tankless Water Heaters Market Awareness – Know The Product • Know the minimum activation flow – Varies from .4 to .78 GPM

• Know the high altitude limitations – Does the unit compensate » If yes – how » What are its limits

• Does the unit offer freeze protection – If yes, what is its low temperature limit » Important, the units are protected but not the pipes

Tankless Water Heaters Market Awareness – Know The Product • Can the unit detect lime buildup – Single unit – Manifold » Preventive maintenance requirements

• Is bigger better?

Saves space, but

» Generally lower efficiency » Possible loss of system redundancy

• Right product for the job – Tankless may not be the answer

Tankless Water Heaters What About Electric Tankless? 28 to 55 KW to compete with gas models • Home needs additional 120-300 amp supply • Communicating with electric utility is critical – Failure to can result in equipment failures

Other concerns

• Can existing infrastructure handle the load • Excess power for new homes – Check with utility

Best opportunity at this time • Commercial applications

Tankless Water Heaters Tankless products offer design flexibility

Indoor

Outdoor

Direct Vent

Tankless Water Heaters • 3 Primary Tankless Designs – Indoor power vent (PV) • Primary – Attics, garages & basements with ample combustion air • Secondary – Confined spaces without ample combustion air

– Outdoor • Mounted on wall - with or without pipe skirt • Mounted in recessed box

– Indoor direct vent (DV) • Primary – Indoor confined spaces • Secondary – Attics, garages & basements with ample combustion air

Tankless Water Heaters

Options and Accessories

Tankless Water Heaters

Optional Pipe Covers •For indoor and outdoor models •Used for cosmetic purposes •Can enhance freeze protection

Tankless Water Heaters Recessed Box – Typical Installation

Tankless Water Heaters Custom Installation – Enhances Aesthetics

Tankless Water Heaters Isolation and de-liming valve kits Lowers installation labor and long-term maintenance costs Easier to install unit when pipe covers and recessed boxes are used Aids in troubleshooting of units in manifold installations Aids in installation of pressure

Tankless Water Heaters Remote Controls • For the end-user - not the contractor • Change temperature settings • Monitors operation of unit • Install in a location convenient for the owner • Can have up to 3 controls per unit on some brands • Contractor should have one in toolbox for troubleshooting

Tankless Water Heaters

Important Design Considerations

Tankless Water Heaters Location is Important •The shorter the vent, the more economical the installation •Install outside •Install on an adjacent outside wall •The closer to the fuel supply, the more economical the installation •Communicate with the fuel supplier •Right meter – right pressure •Plan for upgrades •System is only as good as the contractor installing it!

Tankless Water Heaters Gas Supply is Critical • • • •

Ensure correct pipe size for gas pressure supplied Ensure correct meter set by utility Ensure proper secondary regulators on >2psi systems Post design upgrades – Ensure upgrade is reviewed by all impacted parties • Engineer, utility, plumbing contractor, gas contractor, etc.

Tankless Water Heaters

Venting Category III Appliances Proprietary or Stainless Steel required (Check manufacturers’ specifications)

Cannot combine vents B Vent and Galvanized are not acceptable!

Tankless Water Heaters Indoor Options •Power Vent or Direct Vent units

Side Wall Vent Termination •Preferred indoor installation •Provides lowest indoor installed cost •Provide downward slope IAW Mfg spec.

Tankless Water Heaters Horizontal Venting to Outside Wall

Tankless water heaters are near condensing or condensing, therefore any condensate produced must be handled in accordance with local codes.

Tankless Water Heaters Vertical Venting – Least Preferred Option

Vertical Condensate Trap

Tankless Water Heaters Outdoor Installations – Usually lowest cost option Most units are freeze protected with electrical power • However, plumbing is not •Insulation of pipes and/or heat tracing may be necessary •Pipe covers or recessed boxes can help

Tankless Water Heaters

Proper Sizing It’s GPM - Not GPH!

Tankless Water Heaters Important Commercial Sizing Considerations • Will a storage tank be required – What is the peak demand GPM flow rates » Watch out for high GPM commercial demands

– What is the minimum GPM requirements » Watch our for low flows without recirculation.

• Can you recirc directly through the tankless system – Will this impact the warranty

• What is the temperature rise required – Restaurant, nursing home, etc.

• Right product for the job – Remember, tankless may not be the answer

Tankless Water Heaters Important Residential Sizing Considerations • What is the most logical GPM usage – Number of showers, shower and appliances, Roman tub fill, etc. – Residential fixture uses approximately 80% hot water

• What is the temperature rise required – The greater the temperature rise the lower the capacity – Use lowest inlet temperature at peak occupancy/usage – Or, default to January or February inlet water temperature

• Typical residential fixture uses approximately 80% hot water – Refer to GPM charts furnished by manufacturer – Refer to manufacturer’s sizing program if provided

High Efficiency Tanks Pros – application dependent • Large stored volume • Longer vent options • Lower peak fuel demand Cons • No system redundancy • Limited hot water supply Design dependent • Space • Costs

High Efficiency Tankless Pros • • • • •

Unlimited hot water Multiple installation options Easier to zone System redundancy Green image & economical

Cons – application dependent • No stored capacity • Peak fuel demand - retrofit

Design dependent • Space • Costs

Tankless Water Heaters

Applications and Installations

Tankless Water Heaters Residential Applications •New Construction •Large homes •Spec homes •Multi-family •HUD

•Retrofit •Single family •Multi-family & HUD •Mobile Homes

Tankless Water Heaters

Commercial Applications

Tankless Water Heaters Known Commercial Applications • • • • • • • • • • •

Restaurants Schools Churches Laundromats Hotels Multi-family housing Nursing homes Prisons Dormitories Manufacturing ?????

Tankless Water Heaters Why Foodservice Applications •

Restaurant benefits – Unlimited hot water – Energy Efficient – System redundancy – Saved space • More production space • Lower construction costs

•

New Construction and Retrofit

•

Most all major chains have test installations

Tankless Water Heaters Motels and Hotels • 132 Rooms – 100 Studios – 32 One-Bedroom Suites – Full Bath, Kitchen and dishwasher in each room

• Uses 8 units in manifold

Tankless Water Heaters Large Applications • Removed four 100 gallon 199,000 BTU tanks • Replaced with twelve 199,900 Btu outdoor units • Utility bill reduced by 60% • Expanded facility into old tank location and increased revenue

– 1 x MIC-180 controller

Tankless Water Heaters Typical twelve unit outdoor manifold installation

Tankless Water Heaters

Summary and Q&A

Tankless Water Heaters General Summary - Key Points •Fastest growing segment ever within the plumbing industry •Consumer driven, whether an individual or corporation •Embraced and supported by the natural gas & LP industries •Proper design and proper installation are key to success •Positions your firm as a leader in this growing industry

Tankless Water Heaters Summary – Key Design Considerations What is the normal GPM demand of system •Are there any large commercial loads •Most logical residential usage

What is the temperature rise required •Minimum design cold water inlet temperature •Maximum design outlet temperature required

What are the ratings of the tankless unit •GPM output at required temperature rise •Product design specifications •Pump head requirements •Minimum flow activation

Tankless Water Heaters Summary - Key Design Considerations What are the fuel requirements? •Can the unit operate at the available pressure •What are the piping requirements •Communicate with the utility

What are the venting requirements? •Does it require proprietary or Cat III SS vent material •Will it require a condensate trap

Where will it be installed - indoors or outdoors? •Remember.. The shorter the vent the more economical the installation The closer the fuel source the more economical the installation

And finally, is tankless the right product for the job? •More than likely yes, but………..

Tankless Water Heaters Communicate With The Manufacturer Services that may be offered: • Application and sizing assistance • PC based sizing program • Pressure drop and flow rate curves • Installation specifications • Installation drawings – some engineering approved – Manifold, recirculation, combo-heat, etc. • Product training