HTP EL-399NVWH User Manual

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Elite VWH

NOTE TO CONSUMER: PLEASE KEEP ALL INSTRUCTIONS FOR FUTURE REFERENCE.

This manual must only be used by a qualified heating installer/service technician. Read all instructions in this manual before installing. Perform steps in the order given. Failure to comply could result in substantial property damage, severe personal injury, or death.

INSTALLATION

START-UP

MAINTENANCE

PARTS

Elite VWH Models*

EL-80NVWH / EL-110NVWH EL-150NVWH / EL-220NVWH EL-299NVWH / EL-301NVWH

EL-399NVWH

*“N” denotes natural gas

*“LP” denotes propane gas

*“VWH” denotes Hot Water Supply Boiler

NOTICE: HTP reserves the right to make product changes or updates without notice and will not be held liable for typographical errors in literature.

The surfaces of these products contacted by consumable water contain less than 0.25% lead by weight, as required by the Safe Drinking Water Act, Section 1417.

120 Braley Rd. P.O. Box 429 East Freetown, MA 02717-0429 www.htproducts.com

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IF THE INFORMATION IN THIS MANUAL IS NOT FOLLOWED EXACTLY, A FIRE OR EXPLOSION MAY RESULT, CAUSING

PROPERTY DAMAGE, PERSONAL INJURY, OR LOSS OF LIFE. DO NOT STORE GASOLINE OR OTHER FLAMMABLE VAPORS

AND LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER APPLIANCE.

WHAT TO DO IF YOU SMELL GAS

 Do not try to light any appliance.  Do not touch any electrical switch.  Do not use any phone in your building.  Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions.  If you cannot reach your gas supplier, call the fire department. Installation and service must be provided by a qualified installer,

service agency, or the gas supplier.

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The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels, or to important product information.

DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.

WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.

CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not avoided, may result in property

damage.

FOREWORD

This manual is intended to be used in conjunction with other literature provided with the heater. This includes all related control information. It is important that this manual, all other documents included with this system, and additional publications including the National Fuel Gas Code, ANSI Z223.1-2002, be reviewed in their entirety before beginning any work.

Installation should be made in accordance with the regulations of the Authority Having Jurisdiction, local code authorities, and utility companies which pertain to this type of water heating equipment.

Authority Having Jurisdiction (AHJ) – The Authority Having Jurisdiction may be a federal, state, local government, or individual such as a fire chief, fire marshal, chief of a fire prevention bureau, labor department or health department, building official or electrical inspector, or others having statutory authority. In some circumstances, the property owner or his/her agent assumes the role, and at government installations, the commanding officer or departmental official may be the AHJ.

NOTE: HTP, Inc. reserves the right to modify product technical specifications and components without prior notice.

FOR THE INSTALLER

This appliance must be installed by qualified and licensed personnel. The installer should be guided by the instructions furnished with the heater, and with local codes and utility company requirements. In the absence of local codes, preference should be given to the National Fuel Gas Code, ANSI Z223.1-2002.

INSTALLATIONS MUST COMPLY WITH:

Local, state, provincial, and national codes, laws, regulations and ordinances. The latest version of the National Fuel Gas Code, ANSI Z223.1, from American Gas Association Laboratories, 8501 East Pleasant

Valley Road, Cleveland, OH 44131. In Canada – CGA No. B149 (latest version), from Canadian Gas Association Laboratories, 55 Scarsdale Road, Don Mills, Ontario,

Canada M3B 2R3. Also, Canadian Electrical Code C 22.1, from Canadian Standards Association, 5060 Spectrum Way, Suite 100, Mississauga, Ontario, Canada L4W 5N6.

Code for the installation of Heat Producing Appliances (latest version), from American Insurance Association, 85 John Street, New York, NY 11038.

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NOTICE

The CSD-1 ASME Code, Section CW-400 requires that hot water heating and supply boilers have a) a UL 353 temperature control device, b) at least one (1) temperature-actuated control to shut off the fuel supply when system water reaches a preset operating temperature, c) a high temperature limit control that prevents the water temperature from exceeding the maximum allowable temperature by causing a safety shutdown and lockout, and d) its own sensing element and operating switch.

The temperature control system integrated into the 926 control provided with this heating appliance complies with the requirements of CSD-1 Section CW-400 as a temperature operation control. The control monitors the temperature difference between the inlet and the outlet sensor, which is affected by boiler water flow. If this temperature difference exceeds 55°F (typically because of low water flow or very low heat load), the control will reduce the maximum fan speed. If the temperature difference exceeds 60°F, the control will effectively sense there is little or no water flow or heat load and shut the boiler down. The controller will restart automatically once the temperature difference has dropped below 55°F and the minimum off time (anti-cycle time) has expired. In addition, if the control senses that the outlet water temperature has reached 210°F, the boiler is put into a hard lockout and requires manual reset to restart.

The latest version of the National Electrical Code, NFPA No. 70. NOTE: The gas manifold and controls met safe lighting and other performance criteria when the heater underwent tests specified in

ANSI Z21.13 – latest edition.

TABLE OF CONTENTS

PART 1 – GENERAL SAFETY INFORMATION .......................................................................................................................... 6

A. PRECAUTIONS .......................................................................................................................................................................... 6

B. IMPROPER COMBUSTION ....................................................................................................................................................... 7

C. GAS ............................................................................................................................................................................................ 7

D. WHEN SERVICING THE HEATER ............................................................................................................................................ 7

E. HEATER WATER CHEMISTRY* ................................................................................................................................................ 7

PART 2 – BEFORE YOU START ................................................................................................................................................ 8

A. WHAT’S IN THE BOX ................................................................................................................................................................. 8

B. HOW HEATER OPERATES ....................................................................................................................................................... 8

C. OPTIONAL EQUIPMENT ........................................................................................................................................................... 9

PART 3 – PREPARE HEATER LOCATION ................................................................................................................................ 9

A. BEFORE LOCATING THE HEATER ........................................................................................................................................ 10

B. LEVELING AND DIMENSIONS ................................................................................................................................ ................ 11

C. CLEARANCES FOR SERVICE ACCESS ................................................................................................................................ 11

D. RESIDENTIAL GARAGE INSTALLATION ............................................................................................................................... 13

E. EXHAUST VENT AND INTAKE PIPE....................................................................................................................................... 13

F. PREVENT COMBUSTION AIR CONTAMINATION .................................................................................................................. 14

G. REMOVING A HEATER FROM A COMMON VENT SYSTEM ................................................................................................ 14

H. UNCRATING THE HEATER .................................................................................................................................................... 15

PART 4 – HEATER PIPING ....................................................................................................................................................... 15

A. GENERAL PIPING INFORMATION ......................................................................................................................................... 15

B. RELIEF VALVE ........................................................................................................................................................................ 16

C. BACKFLOW PREVENTER ...................................................................................................................................................... 16

D. SYSTEM WATER PIPING METHODS ..................................................................................................................................... 16

E. CIRCULATOR PUMPS ............................................................................................................................................................. 17

F. INSTALLATION OF THE FLOW SWITCH ................................................................................................................................ 17

G. SCALDING ............................................................................................................................................................................... 18

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H. HIGH VELOCITY CIRCULATOR PUMP .................................................................................................................................. 19

I. PIPING ....................................................................................................................................................................................... 21

J. PIPING DETAILS ...................................................................................................................................................................... 23

PART 5 – VENTING, COMBUSTION AIR, AND CONDENSATE REMOVAL ........................................................................... 26

A. GENERAL ................................................................................................................................................................................ 26

B. APPROVED MATERIALS FOR EXHAUST VENT AND INTAKE PIPE .................................................................................... 27

C. REQUIREMENTS FOR INSTALLATION IN CANADA ............................................................................................................. 28

D. EXHAUST VENT AND INTAKE PIPE LOCATION ................................................................................................................... 29

E. EXHAUST VENT AND INTAKE PIPE SIZING .......................................................................................................................... 32

F. LONGER VENT RUNS ............................................................................................................................................................. 32

G. EXHAUST VENT AND INTAKE PIPE INSTALLATION ............................................................................................................ 33

H. SIDEWALL VENTING .............................................................................................................................................................. 34

I. VERTICAL VENTING................................................................................................................................................................. 35

J. HORIZONTAL VENTING .......................................................................................................................................................... 36

K. UNBALANCED FLUE / VERTICAL VENT ................................................................................................................................ 37

L. VENTING THROUGH AN EXISTING SYSTEM ........................................................................................................................ 37

1. CONCENTRIC VENTING THROUGH AN EXISTING SYSTEM .................................................................................................. 38

2. VENTING AS A CHASE .............................................................................................................................................................. 39

M. INDOOR COMBUSTION AIR INSTALLATION IN CONFINED OR UNCONFINED SPACE .................................................... 40

PART 6 – GAS PIPING .............................................................................................................................................................. 42

A. GAS CONNECTION ................................................................................................................................................................. 42

B. GAS PIPING ............................................................................................................................................................................. 42

C. CHECK INLET GAS PRESSURE............................................................................................................................................. 43

D. HEATER GAS VALVE .............................................................................................................................................................. 44

PART 7 – FIELD WIRING .......................................................................................................................................................... 45

A. INSTALLATION MUST COMPLY WITH: .................................................................................................................................. 45

B. FIELD WIRING TERMINATIONS ............................................................................................................................................. 45

C. FIELD WIRING ................................................................................................ ......................................................................... 45

D. LINE VOLTAGE WIRING FOR STANDARD HEATER ............................................................................................................. 45

E. ALARM CONNECTIONS .......................................................................................................................................................... 45

F. LOW VOLTAGE CONNECTIONS FOR STANDARD HEATER ................................................................................................ 46

G. TANK SENSOR OR MECHANICAL CONTROL ...................................................................................................................... 46

H. SYSTEM / PIPE SENSOR ....................................................................................................................................................... 47

I. OPTIONAL 0-10 VOLT BUILDING CONTROL SIGNAL ............................................................................................................ 47

J. OPTIONAL UL353 LOW WATER CUT-OFF INTERFACE KIT ................................................................................................. 47

K. WIRING OF CASCADE SYSTEM COMMUNICATION BUS .................................................................................................... 47

L. CASCADE MASTER PUMP AND SENSOR WIRING............................................................................................................... 48

M. CASCADE FOLLOWER PUMP AND SENSOR WIRING ........................................................................................................ 48

PART 8 – START-UP PREPARATION...................................................................................................................................... 53

A. CHECK / CONTROL WATER CHEMISTRY ............................................................................................................................. 53

B. CHECK FOR GAS LEAKS ....................................................................................................................................................... 53

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C. CONDENSATE REMOVAL ...................................................................................................................................................... 53

D. FINAL CHECKS BEFORE STARTING HEATER ..................................................................................................................... 54

E. SETTING UP A SINGLE HEATER ........................................................................................................................................... 54

F. SETTING UP A CASCADED SYSTEM .................................................................................................................................... 54

G. LOCKOUT CONDITION ........................................................................................................................................................... 55

H. CASCADE SYSTEM PROGRAMMING .................................................................................................................................... 55

PART 9 – START-UP PROCEDURE ......................................................................................................................................... 56

A. CONTROL OVERVIEW ............................................................................................................................................................ 56

B. NAVIGATION OF THE DISPLAY ............................................................................................................................................. 56

C. OPERATING INSTRUCTIONS ................................................................................................................................................ 57

D. PROGRAMMING HEATER SETTINGS ................................................................................................................................... 57

E. PROGRAMMING THE SYSTEM SETTING ............................................................................................................................. 58

F. SYSTEM SETTING PROGRAM NAVIGATION ........................................................................................................................ 58

G. RESETTING THE MAINTENANCE SCHEDULE ..................................................................................................................... 60

PART 10 – START-UP PROCEDURES FOR THE INSTALLER ............................................................................................... 61

A. HEATER CONTROL STATUS MENU ...................................................................................................................................... 61

B. CASCADE MENU ..................................................................................................................................................................... 62

C. HEATER TEST MODE ............................................................................................................................................................. 63

PART 11 – TROUBLESHOOTING ............................................................................................................................................ 63

A. HEATER ERROR CODE .......................................................................................................................................................... 63

B. HEATER ERROR ..................................................................................................................................................................... 63

C. HEATER FAULT....................................................................................................................................................................... 63

D. USER INTERFACE DISPLAY .................................................................................................................................................. 64

PART 12 – MAINTENANCE ...................................................................................................................................................... 69

A. MAINTENANCE PROCEDURES ............................................................................................................................................. 69

B. COMBUSTION CHAMBER COIL CLEANING INSTRUCTIONS FOR HEATER ...................................................................... 70

C. CLEANING WATER SIDE OF HEAT EXCHANGER ................................................................................................................ 70

D. MAINTAINING THE CONDENSATE SYSTEM ........................................................................................................................ 71

HEATER START-UP REPORT .................................................................................................................................................. 76

MAINTENANCE REPORT ......................................................................................................................................................... 76

MAINTENANCE NOTES ................................................................................................................................................................. 80

HTP CUSTOMER INSTALLATION RECORD FORM ...................................................................................................................... 81

PART 1 – GENERAL SAFETY INFORMATION

A. PRECAUTIONS

This appliance is for indoor installations only. Clearance to combustible materials: 0” top, bottom, sides and back. Left side has all heater mechanical connections. Front must have room for service, 24” recommended. (A combustible door or removable panel is acceptable front clearance.) This appliance has been approved for closet installation. Do not install this appliance directly on carpeting. For installation on combustible flooring. Category IV vent systems only.

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INSTALLER – Read all instructions in this manual before installing. Perform steps in the order given.

USER – This manual is for use only by a qualified heating installer/service technician. Have this heater serviced/inspected by a qualified service technician annually.

FAILURE TO ADHERE TO THE GUIDELINES ON THIS PAGE AND HAVE THIS HEATER SERVICED/INSPECTED ANNUALLY CAN RESULT IN SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.

NOTE: If the heater is exposed to the following, do not operate until all corrective steps have been made by a qualified serviceman:

1. FIRE

2. DAMAGE

3. WATER Any claims for damage or shortage in shipment must be filed immediately against the transportation company by the consignee.

DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN SUBMERGED IN WATER. Immediately call a qualified service technician. The appliance MUST BE replaced if it has been submerged. Attempting to operate an appliance that has been submerged could create numerous harmful conditions, such as a potential gas leakage causing a fire and/or explosion, or the release of mold, bacteria, or other harmful particulates into the air. Operating a previously submerged appliance could result in property damage, severe personal injury, or death.

NOTE: Appliance damage due to flood or submersion is considered an Act of God, and IS NOT covered under product warranty.

Be sure to disconnect electrical power before opening heater cabinet or performing service. Failure to do so could result in an electrical shock that could result in property damage, serious personal injury, or death.

Do not obstruct the flow of combustion and ventilating air. Adequate air must be provided for safe operation. Failure to keep the vent and combustion air intake clear of ice, snow, or other debris could result in property damage, serious personal injury, or death.

NOTE: When inquiring about service or troubleshooting, reference the model and serial numbers from the heater rating label.

B. IMPROPER COMBUSTION

C. GAS

Should overheating or gas supply fail to shut off, do not turn off or disconnect electrical supply to the circulator. Instead, shut off the gas supply at a location external to the appliance.

D. WHEN SERVICING THE HEATER

 To avoid electric shock, disconnect electrical supply before

performing maintenance.

 To avoid severe burns, allow heater to cool.

E. HEATER WATER CHEMISTRY*

 Water pH between 6.0 and 8.0

o Maintain water pH between 6.0 and 8.0. Check with litmus

paper or have it chemically analyzed by water treatment company.

o If the pH differs from above, consult local water treatment

company for treatment needed.

 Hardness less than 7 grains

o Consult local water treatment companies for unusually hard

water areas (above 7 grains hardness).

 Chlorine concentration less than 100 ppm

o Using chlorinated fresh water should be acceptable as levels

are typically less than 5 ppm.

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o Do not connect the heater to directly heat swimming pool or spa water. o Do not fill heater or operate with water containing chlorine in excess of 100 ppm.

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You must not have a direct connection of the potable water system into the heat exchanger. This could cause flow issues, short cycling, and an increase of mineral build-up in the unit. This system is designed to have incoming potable water flow through the storage tank first, then through the heat exchanger. FAILURE TO PIPE THE UNIT PROPERLY WILL VOID THE WARRANTY.

VWH units must be connected to a storage tank. Failure to connect the VWH to a storage tank WILL VOID the warranty.

 *NOTE: It is recommended to clean heat exchanger at least once a year to prevent lime scale buildup. To clean the heat

exchanger, follow the maintenance procedure in Part 12, Section B of this manual.

NOTE: Damages resulting from incorrect installation or from use of products not approved by HTP, Inc. ARE NOT covered by warranty.

PART 2 – BEFORE YOU START

A. WHAT’S IN THE BOX

Also included with the heater:

 Temperature and Pressure Gauge (Part #7450-222)  Pressure Relief Valve (Part #7250P-219 for EL80/110/150, #7350P-065 for EL220/299/301/399)  Intake PVC Tee with Screens  Exhaust PVC Coupling with Screens  Outlet Combination Fitting (Part #7450-235 for EL80/110/150/220, #7450-236 for EL299/301, #7450-237 for EL399)  Flow Switch and Paddles (Part #7250P-517)  Installation Manual  Warranty  CSD-1 Form  H-3 Data Sheet  NAT to LP Conversion Kit (Part #7450P-223) (Included with NAT models)  LP to NAT Conversion Kit (Part #7450P-224) (Included with LP models)

B. HOW HEATER OPERATES

Elite VWH® condensing technology intelligently delivers large amounts of hot water while maximizing efficiency. Outlined below are the features of the system and how they operate:

Stainless Steel Heat Exchanger - The highly efficient stainless steel heat exchanger is designed to use the cold water return from the storage tank and extract the last bit of heat before it is exhausted.

Modulating Combustion System - The combustion system will modulate the output of the burner during operation to match the system demand and achieve the control set point while in operation. The set point can change by internal or external signals which enhance the overall performance of the system.

Control – The integrated control system monitors the system and regulates fan speed to control heater output. This allows the heater to deliver only the amount of heat energy required and nothing more.

The control can regulate the output of multiple heaters through its cascade system function. The cascade system is capable of connecting up to eight heaters together in such a way that they function as one heater system. This allows for greater turn down ratios and provides systematic control of the multiple heaters in an installation to minimize downtime and maximize efficiency.

The cascade system works by establishing one heater as the master and the other connected heaters as followers. The master heater requires a sensor to provide feedback on set point temperature in order to adjust heating input from the connected heaters. Each cascaded heater will have its own pump to provide maximum flow and control heat exchanger flow rate.

Text Display and Operational LED Light Indicators – The display allows the user to change the system parameters and monitor system outputs.

Gas Valve – Senses suction from the blower, allowing gas to flow only if powered and combustion air is flowing. All Metal Integrated Venturi – Controls air and gas flow into the burner. Burner – Constructed of high grade stainless steel, the burner uses premixed air and gas fuel and provides a wide range of firing rates.

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Carefully consider installation when determining heater location. Please read the entire manual before attempting installation. Failure to properly take factors such as heater venting, piping, condensate removal, and wiring into account before installation could result in wasted time, money, and possible property damage and personal injury.

Spark Ignition – The burner is ignited by applying high voltage through the system spark electrode. This causes the spark from the electrode to ignite mixed gas off of the burner.

Supply Water Temperature Sensor – This sensor monitors the heater outlet water temperature (System Supply). The control adjusts the heater firing rate so the supply temperature will match the heater set point.

Return Water Temperature Sensor – This sensor monitors the heater return water temperature (System Return). Flue Sensor – Monitors flue temperature and adjusts firing rate. Temperature and Pressure Gauge – Allows the user to monitor system temperature and pressure. Electrical field connections with terminal strips – The electrical cover allows easy access to the line voltage and low voltage

terminals strips which are clearly marked to facilitate wiring of the heater. Condensation Collection System – This heater is a high efficiency appliance, therefore the heater will produce condensate. The

collection system has a float switch which monitors the condensation level and prevents condensation from backing up into the combustion system. Inside the collection system there is a built in trap which seals the combustion system from the connected drain. This condensate should be neutralized to avoid damage to the drainage system or piping.

Flow Protection – The supplied flow switch is designed to protect the heater in the event of low flow conditions. The heater control will also monitor flow through the heat exchanger by monitoring the return and supply sensor and will shut down the burner before overheating occurs.

0-10 Volt Input – Allows Installer to connect a BMS (Building Management System) to control the heater. Condensate Flue Check System – The check system prevents exhaust from the heat exchanger from backing up into cabinet. Pump Service Mode – Allows manual operation of pumps to commission system and check pump operation.

C. OPTIONAL EQUIPMENT

Below is a list of optional equipment available from HTP. These additional options may be purchased through your HTP distributor:

 Wall Mount Bracket (Part # 7450P-211)  System Sensor (Part # 7250P-324)  Indirect Tank Sensor (Part # 7250P-325)  2” PVC Concentric Vent Kit (Part # KGVAT0501CVT)  3" PVC Concentric Vent Kit (Part # KGAVT0601CVT)  2” Stainless Steel Outside Termination Vent Kit (Part # V500)  3” Stainless Steel Outside Termination Vent Kit (Part # V1000)  4” Stainless Steel Outside Termination Vent Kit (Part # V2000)  6” Stainless Steel Outside Termination Vent Kit (Part # V3000)  3” Polypro Vent Kit (Part # 8400P-001)  3” Polypro Pipe (33’ length Part # 8400P-002, 49.5’ length Part # 8400P-003)  U.L. 353 Compliant Low Water Cut-Off Interface Kit with Manual Reset (Part # 7450P-225)  Manual Reset High Limit (Part # 7450P-217)  Alarm System (Part # 7350P-602) (to monitor any failure)  PC Connection Kit (Part # 7250P-320)  Condensate Neutralizer (Part # 7450P-212 for EL-80/110/150/220/299/301, Part # 7350P-611 for EL-399)

NOTE: When using an optional system sensor, pipe insulation must be wrapped around it to improve temperature measurement accuracy and increase overall system efficiency.

PART 3 – PREPARE HEATER LOCATION

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Incorrect ambient conditions can lead to damage to the heating system and put safe operation at risk. Ensure that the heater installation location adheres to the information included in this manual. Failure to do so could result in property damage, serious personal injury, or death.

Failure of heater or components due to incorrect operating conditions IS NOT covered by product warranty.

The service life of the heater’s exposed metallic surfaces, such as the casing, as well as internal surfaces, such as the heat exchanger, are directly influenced by proximity to damp and salty marine environments. In such areas, higher concentration levels of chlorides from sea spray coupled with relative humidity can lead to degradation of the heat exchanger and other heater components. In these environments, heaters must not be installed using direct vent systems which draw outdoor air for combustion. Such heaters must be installed using room air for combustion. Indoor air will have a much lower relative humidity and, hence, potential corrosion will be minimized.

This heater is certified for indoor installations only. Do not install the heater outdoors. Failure to install this heater indoors could result in substantial property damage, severe personal injury, or death.

Failure to keep heater area clear and free of combustible materials, liquids, and vapors can result in substantial property damage, severe personal injury, or death.

Do not mount the heater to a hollow wall. Mount to the studs only. Failure to do so will result in substantial property damage, and could result in severe personal injury or death.

A. BEFORE LOCATING THE HEATER

1. Installation Area (Mechanical Room) Operating Conditions

 Ensure ambient temperatures are higher than 32oF/0oC and lower than 104oF/40oC.  Prevent the air from becoming contaminated by the products, places, and conditions listed in this manual, Part 3, Section F.  Avoid continuously high levels of humidity  Never close existing ventilation openings

2. Check for nearby connections to:

 System water piping  Venting connections  Gas supply piping  Electrical power  Condensate drain

3. Check area around heater. Remove any combustible materials, gasoline, and other flammable liquids.

4. Gas control system components must be protected from dripping water during operation and service.

5. If the heater is to replace an existing heater, check for and correct any existing system problems, such as:

 System leaks  Location that could cause the system and heater to freeze and leak.  Incorrectly-sized expansion tank

6. Clean and flush system when reinstalling a heater. NOTE: When installing in a zero clearance location, it may not be possible to read or view some product labeling. It is recommended to

make note of the heater model and serial number.

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Use extreme care not to drop the heater or cause bodily injury while lifting or mounting the heater onto the optional wall mount bracket. Failure to do so will result in property damage, and could result in severe personal injury or death.

Gas conversion should be performed BEFORE the heater is installed. Carefully follow the gas conversion instructions when performing the conversion. Failure to do so could result in property damage, severe personal injury, or death.

Space must be provided with combustion/ventilation air openings correctly sized for all other appliances located in the same space as the heater. The heater cover must be securely fastened to prevent it from drawing air from the heater room. This is particularly important if the heater is in a room with other appliances. Failure to comply with the above could result in substantial property damage, severe personal injury, or death.

In order for the condensate to properly flow out of the collection system, the area where you locate the heater must be level. The heater comes equipped with leveling feet. Should you find the floor beneath the heater is uneven, adjust the leveling feet with a wrench.

Figure 1 – Leveling

Figure 2 – Recommended Service Clearances

B. LEVELING AND DIMENSIONS

C. CLEARANCES FOR SERVICE ACCESS

See Figure 2 for recommended service clearances. If these minimum clearances are not provided, it may not be possible to service the heater without removing it from the space.

MINIMUM CLEARANCES FROM COMBUSTIBLE MATERIALS

 Hot water pipes – at least 1” from combustible materials.  Exhaust vent pipe – at least 1” from combustible materials.

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Figure 3 – LP-285-B

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Vents must be properly supported. The heater exhaust and intake connections are not designed to carry heavy weight. Vent support

brackets must be within 1’ of the heater and the balance at 4’ intervals. Venting must be readily accessible for visual inspection for the first 3’ from the heater.

Figure 4

D. RESIDENTIAL GARAGE INSTALLATION

PRECAUTIONS

If the heater is located in a residential garage, per ANSI Z223.1:

 Mount the bottom of the heater a minimum of 18” above the floor of the garage, to ensure the burner and ignition devices are

well off the floor.

 Locate or protect the heater so it cannot be damaged by a moving vehicle.

E. EXHAUST VENT AND INTAKE PIPE

The heater is rated ANSI Z21.13 Category IV (pressurized vent, likely to form condensate in the vent), and requires a special vent system designed for pressurized venting.

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Ensure that the intake air will not contain any of the contaminants below. For example, do not pipe intake near a swimming pool. Avoid areas subject to exhaust fumes from laundry facilities. These areas always contain contaminants. Contaminated air will damage the heater, resulting in possible substantial property damage, severe personal injury, or death.

PRODUCTS TO AVOID

AREAS LIKELY TO HAVE CONTAMINANTS

Spray cans containing fluorocarbons

Dry cleaning/laundry areas and establishments

Permanent wave solutions

Swimming pools

Chlorinated waxes/cleaners

Metal fabrication plants

Chlorine-based swimming pool chemicals

Beauty shops

Calcium chloride used for thawing

Refrigeration repair shops

Sodium chloride used for water softening

Photo processing plants

Refrigerant leaks

Auto body shops

Paint or varnish removers

Plastic manufacturing plants

Hydrochloric or Muriatic acid

Furniture refinishing areas and establishments

Cements and glues

New building construction

Antistatic fabric softeners used in clothes dryers

Remodeling areas

Chlorine-type bleaches, laundry detergents, and cleaning solvents

Garages and workshops

Adhesives used to fasten building products

NOTE: DAMAGE TO THE HEATER CAUSED BY EXPOSURE TO CORROSIVE VAPORS IS NOT COVERED BY WARRANTY.

(Refer to the limited warranty for complete terms and conditions).

Do not install the heater into a common vent with any other appliance. This will cause flue gas spillage or appliance malfunction, resulting in possible substantial property damage, severe personal injury, or death.

Failure to follow all instructions can result in flue gas spillage and carbon monoxide emissions, causing severe personal injury or death.

Figure 5 - CO Warning Label

You must also install air intake piping from outdoors to the heater flue adaptor. The resultant installation is categorized as direct vent (sealed combustion). Note: To prevent combustion air contamination, see Table 1 in this section when considering exhaust vent and intake pipe termination.

Exhaust and intake must terminate near each other and may be vented vertically through the roof or out a side wall. Exhaust vent and intake piping methods are detailed in the Venting Section. Do not attempt installation using any other means. Be sure to locate the heater so exhaust vent and intake piping can be routed through the building and properly terminated. The exhaust vent and intake piping lengths, routing and termination method must all comply with methods and limits given in the venting section.

F. PREVENT COMBUSTION AIR CONTAMINATION

Install intake piping for the heater as described in the Venting section. Do not terminate exhaust vent in locations that can allow contamination of intake air.

Table 1

G. REMOVING A HEATER FROM A COMMON VENT SYSTEM

When removing an existing heater, the following steps must be followed.

1. Seal any unused openings in the common venting system.

2. Visually inspect the venting system for proper size and horizontal pitch to determine if there is blockage, leakage, corrosion or other deficiencies that could cause an unsafe condition.

3. If practical, close all building doors, windows and all doors between the common venting system and other spaces in the building. Turn on clothes dryers and any appliances not connected to the common venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, at maximum speed. Do not operate a summer exhaust fan. Close all fireplace dampers.

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UNCRATING HEATER – Any claims for damage or shortage in shipment must be filed immediately against the transportation company by the consignee.

Cold weather handling – If heater has been stored in a very cold location (below 0oF) before installation, handle with care until the plastic components come to room temperature.

Failure to follow the instructions in this section WILL VOID the warranty and may result in property damage, serious injury, or death.

DO NOT pipe this water heater with black iron, galvanized steel, steel, or lead pipe. Doing so will result in premature product failure and property damage, and WILL VOID the product warranty.

The building piping system must meet or exceed the piping requirements in this manual.

Use two wrenches when tightening water piping at the heater. Use one wrench to prevent the heater return or supply line from turning. Failure to prevent piping connections from turning could cause damage to heater components.

Never use dielectric unions or galvanized steel fittings when connecting to a stainless steel storage tank or heater. Failure to follow this instruction can lead to premature failure of the heater system. Such failures ARE NOT covered by warranty.

4. Place in operation the appliance being inspected. Follow the lighting instructions. Adjust the thermostat so the appliance will operate continuously.

5. Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or candle or smoke from a cigarette.

6. After it has been determined that each appliance remaining connected to common venting system properly vents when tested as outlined, return doors, windows, exhaust fans, fireplace dampers and any other gas burning appliance to their previous condition of use.

7. Any improper operation of the common venting system should be corrected so the installation conforms to the National Fuel Gas Code, ANSI Z223.1. When resizing any portion of the common venting system, the common venting system should be resized to approach the minimum size as determined using the appropriate tables in Appendix G in the National Fuel Gas Code, ANSI Z 223.1.

H. UNCRATING THE HEATER

Remove all sides of the shipping crate to allow the heater to be lifted into its installation location. The heater is also equipped with leveling feet that can be used to level the heater properly on an uneven location surface. If surface flooring is rough, take care when sliding heater into position, as you could catch the leveling feet and damage the heater.

PART 4 – HEATER PIPING

Plumbing of this product should only be done by a qualified, licensed plumber in accordance with all local plumbing codes. The heater is designed to be connected to a storage tank to supply domestic hot water. HTP offers 60/80/119/175 gallon size storage tanks in either stainless steel or glass-lined construction. These storage tanks will be directly connected to the heater supply and return connection.

A. GENERAL PIPING INFORMATION

NOTE: The addition of a high temperature limiting device is important if the heater is to be connected to a domestic hot water system. Connect the cold water supply to both the storage bottom port and the supply side of the heater (shown in Piping Details, Section J). It

is important that you install a flow check on the supply line of the heater BEFORE connecting the feed line to the storage tank. This

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To avoid water damage or scalding due to relief valve operation:

 Discharge line must be connected to relief valve outlet and run to a safe place of disposal. Terminate the discharge line in a

manner that will prevent possibility of severe burns or property damage should the relief valve discharge.

 Discharge line must be as short as possible and the same size as the valve discharge connection throughout its entire length.  Discharge line must pitch downward from the valve and terminate at least 6” above the floor drain, making discharge clearly

visible.

 Discharge line shall terminate plain, not threaded, with a material serviceable for temperatures of 375oF or greater.  Do not pipe discharge to any location where freezing could occur.  No shutoff valve may be installed between the relief valve and heater or in the discharge line. Do not plug or place any

obstruction in the discharge line.

 Test the operation of the relief valve after filling and pressurizing the system by lifting the lever. Make sure the valve

discharges freely. If the valve fails to operate correctly, replace it with a new relief valve.

 Test relief valve at least once annually to ensure the waterway is clear. If valve does not operate, turn the heater “off” and call

a plumber immediately.

 Take care whenever operating relief valve to avoid scalding injury or property damage.  For heaters installed with only a pressure relief valve, the separate storage vessel must have a temperature and pressure

relief valve installed. This relief valve shall comply with Relief Valves for Hot Water Supply Systems, ANSI Z21.22 CSA4.4.

FAILURE TO COMPLY WITH THE ABOVE GUIDELINES COULD RESULT IN FAILURE OF RELIEF VALVE OPERATION, RESULTING IN POSSIBILITY OF SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.

Expansion tanks must be sized according to total system volume. This includes all length of pipe, all fixtures, heaters, etc. Failure to properly size system expansion could result in wasted time, money, and possible property damage, personal injury, or death.

Elite VWH EXPANSION TANK SIZING

EL-80 VWH

1.4 Gallons + Storage Tank Selected (60, 80, 119, or 175)

EL-110 VWH

1.7 Gallons + Storage Tank Selected (60, 80, 119, or 175)

EL-150 VWH

2.0 Gallons + Storage Tank Selected (60, 80, 119, or 175)

EL-220 VWH

2.6 Gallons + Storage Tank Selected (60, 80, 119, or 175)

EL-299/301 VWH

3.1 Gallons + Storage Tank Selected (60, 80, 119, or 175)

EL-399 VWH

3.7 Gallons + Storage Tank Selected (60, 80, 119, or 175)

allows the cold feed to flow through the storage tank first. It is recommended that you install shut off valves on the cold feed line for future ease of service. If there is a back flow preventer or any type of no return valve in the system, then you must install an additional tee for a suitable potable hot water expansion tank. Connect the storage tank return line to the return connection located on the heater (shown in Piping Details, Section J). Then connect the storage tank hot water outlet to the hot water plumbing lines.

B. RELIEF VALVE

Connect discharge piping to a safe disposal location following the guidelines below.

C. BACKFLOW PREVENTER

Use a backflow preventer specifically designed for potable water installations. This valve should be installed on the cold water fill supply line per local codes (see Piping Details, Section J).

D. SYSTEM WATER PIPING METHODS

EXPANSION TANK AND MAKE-UP WATER

1. Ensure that the expansion tank is designed for potable water installations and sized to correctly handle system water volume and temperature.

Table 2

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Undersized expansion tanks cause system water to be lost from the relief valve, causing make-up water to be added. Eventual heater failure can result due to excessive make-up water addition. SUCH FAILURE IS NOT COVERED BY WARRANTY.

DO NOT install automatic air vents on closed type expansion tank systems. Air must remain in the system and return to the tank to provide an air cushion. An automatic air vent would cause air to leave the system, resulting in improper operation of the expansion tank.

Water temperature above 140oF requires the circulator to run continuously. Water hardness must be between 5 and 7 grains. Hardness above 7 grains will damage the heat exchanger and shorten the service life of the heater.

DO NOT use the heater circulator in any location other than the ones shown in this manual. The heater circulator location is selected to ensure adequate flow through the heater. Failure to comply with this caution could result in unreliable performance and nuisance shutdowns from insufficient flow.

ELITE VWH MODEL

PADDLE SIZE

EL-80/110/150/220 VWH

EL-299/301 VWH

EL-399 VWH

N/A

2. The expansion tank must be located as shown in Part 4, Heater Piping, or following recognized design methods. See expansion tank manufacturer’s instructions for details.

E. CIRCULATOR PUMPS

Every VWH system requires special attention to pump size in order to overcome pressure drop through the heater and its related piping. All circulators installed on the VWH system must be designed for potable water installations. For pressure drop, see Table 6.

F. INSTALLATION OF THE FLOW SWITCH

1. Choosing the correct flow paddle: Your heater comes with a flow switch and four flow paddles. The paddle you use depends on the model of the heater.

Table 3

2. Attach flow paddle as shown.

3. Thread outlet combination fitting onto supply outlet of heater using pipe dope.

4. Thread flow switch into outlet combination fitting using pipe dope, making certain the FLOW arrow points in the correct direction.

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When raising tank temperature, you increase the risk of scalding. Please use a water tempering or mixing valve and extreme caution when raising tank temperature to lessen the chance of scalds. Consult codes for conformance.

APPROXIMATE TIME /

TEMPERATURE RELATIONSHIPS IN SCALDS

120oF

More than 5 minutes

125oF

1 ½ to 2 minutes

130oF

About 30 seconds

135oF

About 10 seconds

140oF

Less than 5 seconds

145oF

Less than 3 seconds

150oF

About 1 ½ seconds

155oF

About 1 second

Table 4

5. Thread relief valve into outlet combination fitting using pipe dope.

6. Thread temperature and pressure gauge into outlet combination fitting using pipe dope.

7. Connect red wire from flow switch to heater wire harness.

8. When installation is complete, power up the heater and program unit set point. *Please note that these illustrations are meant to

show system piping concept only. The installer is responsible for all equipment and detailing required by local codes.

G. SCALDING

This water heater can deliver scalding water at any faucet in the system. Be careful whenever using hot water to avoid scalding injury. Certain appliances such as dishwashers and automatic clothes washers may require increased water temperature. By setting the thermostat on this water heater to obtain the increased water temperature required by these appliances, you may create the potential for scald injury.

To protect against injury, you should install a mixing valve in the water system. This valve will reduce point of discharge temperature by mixing cold and hot water in branch supply lines. Such valves are available from your local plumbing supplier.

The following chart details the relationship of water temperature and time with regard to scald injury and may be used as a guide in determining the safest water temperature for your applications.

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MINIMUM HEATER FLOW RATES

MODEL

MINIMUM FLOW (GPM)

EL-80 VWH

5.3

EL-110 VWH

7.3

EL-150 VWH

EL-220 VWH

14.6

El-299/301 VWH

El-399 VWH

ELITE VWH CIRCULATORS

MODEL

CIRCULATOR

PART #

FLANGE SIZE

FLANGE PART #

EL-80 VWH

009-SF5

7450P-239

1” NPT

7450P-242

EL-110 VWH

0011-SF4

7450P-240

1” NPT

7450P-242

EL-150 VWH

0013-SF3

7450P-241

1” NPT

7450P-242

EL-220 VWH

0013-SF3

7450P-241

1” NPT

7450P-242

EL-299/301 VWH

2400-20S

7250P-605

1 ¼” NPT

7250P-603

EL-399 VWH

2400-50S

7250P-606

1 ½” NPT

7250P-604

HEAT EXCHANGER PRESSURE DROP CHART

Model

Flow Rate Δ P’

Flow Rate 6 GPM

7 GPM

GPM 9 GPM

GPM

11 GPM

GPM

EL-80

10’

14’

17’

21’

26’ * * * * * * * * * * * *

EL-110 * *

15’

17’

22’

25’

33’ * * * * * * * * * *

EL-150 * * * *

12’

15’

17’

19’

22’

27’ * * * * * *

EL-220 * * * * * * * * * 8’

10’

11.5’

13’

15’

16.5’

17’

19’

EL-299

EL-301

* * * * * * * * * * * * * * 13’

14’

15’

EL-399 * * * * * * * * * * * * * * * *

Flow Rate

GPM

EL-80 * * * * * * * * * * * * * * * *

EL-110 * * * * * * * * * * * * * * * * * EL-150 * * * * * * * * * * * * * * * *

EL-220

21’

23’

24’ * * * * * * * * * * * * * *

EL-299

EL-301

16.5’

18’

20’

22’

24’

26’

29’

33’

36’ * * * * * * * *

EL-399 * * * 12.9’

13.6’

14’

15.7’

17’

18’

19.4’

21’

22.5’

26’

28’

31’

34’

39’

Table 7 - *Do not operate heater at these flow settings as it will damage the heat exchanger or related components cause by excessive flow

rates or minimum flow rates.

H. HIGH VELOCITY CIRCULATOR PUMP

The heat exchanger has a minimum total water volume that must be taken into account when sizing the circulator. These minimum water volumes are listed in Table 5 below.

Table 5 – Minimum Heat Exchanger Water Volumes

Table 6 ELITE PUMP KITS

 Elite 80 VWH – Part # 7450P-246  Elite 110 VWH – Part # 7450P-247  Elite 150 and Elite 220 VWH – Part # 7450P-248  Elite 299/301 VWH – Part # 7450P-249  Elite 399 VWH – Part # 7450P-250

The chart below represents the various system design temperature rise through the heater along with their respective flows and friction loss, which will aid in circulator selection.

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MULTIPLE HEATER MANIFOLD PIPING

Flow Rate (GPM)

100

110

Pipe Dia. (Inches)

2 2 2 2 2

2½

2½ 3 3 3 3 3 3

MULTIPLE HEATER MANIFOLD PIPING

Flow Rate (GPM)

120

132

150

160

170

179

200

210

239

240

250

255

300

340

350

400

425

510

595

680

Pipe Dia. (In.)

4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 6 6

0 50 100 150 200 250

Pipe Diameter Size (Inches)

Combined Boiler Water Flow (GPM)

Multiple Boiler Manifold Piping

SYSTEM TEMPERATURE RISE CHART

Model

20°Δt

25°Δt

30°Δt

Ft / Friction

Flow Rate

Ft / Friction

Flow Rate

Ft / Friction

Flow Rate

EL-80

17’

8 GPM

10’

6.6 GPM

7’

5.3 GPM

EL-110

25’

11 GPM

17’

9.1 GPM

12’

7.3 GPM

EL-150

27’

15 GPM

17’

12.5 GPM

12’

10 GPM

EL-220

19’

22 GPM

13’

18.3 GPM

12’

14.6 GPM

EL-299

EL-301

29’

29 GPM

18’

24.5 GPM

13’

20 GPM

EL-399

39’

39 GPM

19’

32.5 GPM

13’

26 GPM

Table 8

The chart below represents the combined flow rates and pipe sizes when using multiple heaters to design the manifold system for the primary circuit. To size, simply add up the number of heaters and the required flow rates for the system design temperature.

Example: (5) EL-220 Heaters® with a design of 20°Δt degree temperature rise with each heater having an individual flow rate of 22 GPM. To correctly size the manifold feeding these (5) heaters you would need a pipe size of 4”.

Table 9

Figure 6

Table 10

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Water temperature above 140oF requires the circulator pump to run continuously and must have a water hardness of between 5 and 7 grains. Hardness above 7 grains will damage the heat exchanger and shorten the service life of the heater.

MINIMUM VWH PIPE SIZES

EL-80/110/150/220 VWH

1” NPT or Copper

EL-299/301 VWH

1 ¼” NPT or Copper

EL-399 VWH

1 ½” NPT or Copper

Water chemistry* Sodium less than 20 mGL Water pH between 6.0 and 8.0

 Maintain heater water pH between 6.0 and 8.0. Check with litmus paper or have it chemically analyzed by a water treatment

company.

 If the pH differs from above, consult local water treatment company for treatment needed.

Hardness less than 7 grains

Consult local water treatment companies for unusually hard water areas (above 7 grains hardness).

Chlorine concentration less than 100 ppm

 Using chlorinated fresh water should be acceptable since drinking water chlorine levels are typically less than 5 ppm.  Do not connect the heater to directly heat swimming pool or spa water.  Do not fill heater or operate with water containing chlorine in excess of 100 ppm.

*NOTE: It is recommended you clean heat exchanger at least once a year to prevent lime scale buildup. Follow the maintenance procedure to clean the heat exchanger in the Maintenance Section (Part 12 of this manual).

Hardness: 7 grains Chloride levels: 100 ppm pH levels: 6-8 TDS: 2000 ppm Sodium: 20 mGL

Piping components Water heating system piping:

Water heater system piping MUST be sized per technical pipe requirements listed in Table 9 and Table 10. Reducing pipe size can restrict flow rate through the water heater, causing inadvertent short cycling and poor system performance.

Check valves:

Field supplied. Check valves are recommended for installation as shown in Piping Details.

Water heater isolation valves:

Field supplied. Full port ball valves are required. Failure to use full port ball valves could result in a restricted flow rate through the water heater.

Anti-scald mixing valve:

Field supplied. An anti-scald mixing valve is recommended when storing domestic hot water above 115°F.

Unions: Field supplied: Recommended for unit serviceability. DO NOT USE DIELECTRIC UNIONS! ONLY BRASS, COPPER, OR STAINLESS STEEL.

Pressure relief valve:

Factory supplied on Heater. The pressure relief valve is sized to ASME specifications. Storage tank may require additional relief valves depending on local codes.

Table 11

I. PIPING

The heater is designed to function in an open loop hot water supply system. We have included a temperature and pressure gauge that allows the user to monitor the system pressure and outlet temperature from the heater. It is important to note that the heater has a minimal amount of pressure drop and must be calculated when sizing the circulators.

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Install the heater so the gas ignition system components are protected from water (dripping, spraying, etc.). Allow clearance for basic service of heater circulator, valves and other components.

Observe the minimum 1” clearance around all uninsulated hot water pipes when openings around pipes are not protected by noncombustible materials.

Basic steps are listed below, with illustration that will guide you through the installation of the heater.

1. Connect the system return marked “Heater Return”.

2. Connect the system supply marked “Heater Supply”.

3. Install a circulator as shown in piping details (this section). Make sure the circulator is properly sized for the system and friction loss.

4. Install an expansion tank on the system. Consult the expansion tank manufacturer’s instruction manual (see Part 4, Section D for water volume) for specific information relating to expansion tank installation. Size the expansion tank for the required system volume and capacity.

5. Install a drain valve at the lowest point of the system. Note: The heater cannot be drained completely of water without purging the unit with an air pressure of 15 PSI.

6. The relief valve and temperature and pressure gauge are included in the accessory kit. A discharge line should be installed 6” above the drain in the event of a pressure relief. The pipe size must be the same size as the relief valve outlet. NEVER BLOCK THE OUTLET

OF THE SAFETY RELIEF VALVE.

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J. PIPING DETAILS

Elite VWH with Storage Tank

Figure 7

NOTES:

1. This drawing is meant to show system piping concept only. Installer is responsible for all equipment & detailing required by local codes.

2. Heater circulator must be rated for open loop application. Do not use cast-iron circulators.

3. Heater circulator(s) operate continuously.

4. Piping to the water storage tank must be at least the size of the heater return and supply connections.

5. See Table 10 for minimum pipe sizing.

6. All pipes are shown with isolation flanges or full port ball valves for isolation. The alternative is standard flanges with full port ball valves and a separate flow check valve.

7. Install a minimum of 12 diameters of straight pipe upstream of all circulators and check valves.

8. Install vacuum relief valve in accordance with local code requirements.

9. All multiple heaters and multiple storage tanks must be installed with reverse return piping as shown.

10. Anti-scald rated mixing valve is recommended on all tanks if the hot water temperature leaving the tank is above 119oF.

11. Expansion tank must be rated for use with potable water.

12. Use either indirect/tank sensor or system/pipe sensor mounted on common return to the heater.

13. Aquastat or system/pipe sensor connects to DHW sensor input on heater.

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Elite VWH with Two Storage Tanks

Figure 8