Lochinvar 497 - 2067 Domestic water heaters, Water velocity control, Maximum Water Flow

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Installation & Service Manual

7 Domestic water heaters

This section applies only to those units used to supply potable hot water for domestic use. The water heater must be installed with a storage tank.

This section contains specific instructions for those units used to supply domestic hot water. All warnings, cautions, notes and instructions in the general installation and service sections apply to these instructions. Water heaters are designed for installation with a properly sized storage tank. The use of a properly sized pump and the control of water velocity, as explained below, are important for correct operation of your water heater.

Water velocity control

To ensure proper velocity through the NOTICE heat exchanger, you must regulate the

temperature rise across the heat exchanger from inlet to outlet. Do this upon initial installation and periodically recheck.

The correct temperature rise across the heat exchanger ensures proper velocity in the tubes. This will yield long life and economical operation from your hot water heater. Excessive lime build up in the tube is caused by too low velocity through the tubes. Excessive pitting or erosion in the tube is caused by too high velocity through the tubes. Take care to measure temperature rise and maintain a velocity as follows:

Initial set-up of maximum water flow

On initial start-up, the maximum water flow through the heat exchanger must be manually set before normal operation begins.

TABLE - 7A

MAXIMUM WATER FLOW

CAUTION: The maximum flow rate through a water heater with a copper heat exchanger must be set to provide and not exceed the following flow:

Model

Maximum

Flow

 

 

 

497, 647, and 747

55 GPM

 

 

987, 1257, 1437, 1797, and 2067

90 GPM

 

 

If higher flow rates are required through the water heater, an optional Cupro Nickel heat exchanger is available. Consult the factory for specific application requirements.

The heat exchanger is capable of operating within the design flow rates required for the water heater, storage tank(s), and connecting piping. Erosion of the finned copper tubes may occur if the flow rate exceeds the maximum allowable flow rate through the water heater. The maximum flow rate through the water heater must be adjusted. Maximum flow on Models 497 - 747 is 55 GPM and 90 GPM on Models 987 - 2067. Flow rate can be determined by measuring the temperature rise through the water heater when it is firing at full rate input.

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TABLE 7B

 

Temperature Rise Chart

Model

 

Temperature

 

Rise

 

 

497

 

15°F

647

 

19°F

747

 

22°F

987

 

18°F

1257

 

23°F

1437

 

26°F

1797

 

32°F

2067

 

37°F

1.With the pump running and the water heater off, the inlet and outlet thermometers should read the same temperatures. If they do not, an adjustment must be made to your final calculation.

2.Turn the water heater “On” and allow time for the temperature to stabilize. Record the difference between the inlet and outlet temperatures. This difference will be the “temperature rise”.

3.Compare the temperature rise on the heater with the required temperature rise in Table 7B. Should adjustment be needed, proceed as follows:

If the temperature rise is too high, the water velocity is too low. Check the following:

1.Check for restrictions in the outlet of the water heater.

2.Be sure all valves are open between the water heater and the tank.

3.Check the pump to be sure it is running properly and that the pump motor is running in the proper direction (see arrow on volute housing).

4.Be sure the installed circulation pipes between the water heater and storage tank are not less than 2 1/2'' in diameter on Models 987 - 2067.

5.Common manifold piping for multiple unit installations will require larger minimum pipe sizes and tank circulating tappings to ensure proper flow. See Table 7C on page 53.

If the temperature rise is too low, the water velocity is too high. Adjust as follows:

1.Slowly throttle the valve on the outlet side of the water heater until the temperature rise is steady at the required temperature rise as noted in Table 7A.

2.Sustained high water velocity and low temperature rise may result in pitting or erosion of the copper tubes in the heat exchanger. This is a non-warrantable failure. Temperature rise must be properly adjusted to achieve the specified flow rate.

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Contents What to do if YOU Smell GAS Save this manual for future referenceContents Warranty Please read before proceedingSpecial instructions Checking equipmentSafety information Owner warningPrevention of freezing CodesCopper-fin How it works Copper-fin How it works Models 987 2067 Front View Models 987 2067 Rear View Ratings Copper-fin =B=R RatingCopper-fin Specifications Installation Determine unit locationLocating the unit Indoor clearances from combustible constructionOutdoor boiler installation Shut-down and drainingFreeze protection Pump operationFreeze Protection for a Heating Boiler System if required Combustion and Ventilation AirMinimum Recommended Combustion AIR Supply to Equipment Room Number3Combustion air filter Models 497 Combustion air filterOutside Combustion Air, Using Ducts Combustion Air OptionsOutside Combustion Air, No Ducts Exhaust Fans Combustion Air from an Interior SpaceVenting General informationVenting support Vertical vent termination clearances and locationVent system options Barometric damper locationFlue Pipe Sizes Model Flue Size Conventional negative draft venting Negative draftFlue outlet piping Common venting systemsMasonry chimney installation Inspection of a masonry chimneyOutdoor installation venting Outdoor vent/air inlet locationOutdoor vent kit Outdoor Vent Kits Model Pump Cover Without Pump CoverConnecting to gas supply Gas piping Gas connectionsGas pressure test Inlet GAS Pressure Natural ModelSuggested GAS Pipe Size for Single Unit Installations Gas connectionGas train and controls Fittings to Equivalent Straight PipeGAS Piping Size Chart Combination gas valvesVenting of combination gas valves Checking gas supply pressureGas manifold pressure adjustment 3Measuring gas supply pressure at combination gas valve4Measuring manifold gas pressure Nat. GasWater connections Pressure Drop Chart Water connections heating boilers onlyBoiler circulator requirements Minimum boiler water temperatures Low system water volumeRun Cycle Output Minimum System Load Temp. Rise 8.33 60 Min Low temperature return water systems System Temperature Rise ChartRadiant floor and snow melt heating systems LTV Valve Kits Model LTV Valve KITCommon Manifold Size Min Models 497 Number of Units GPMDiameter Common Manifold Size Min Models 987 Number of Units6Primary/secondary piping of multiple boilers 7Boiler with low temperature bypass 8Primary/secondary piping with buffer tank Installation with a chilled water system Typical heating boiler installationsBoiler flow rate General plumbing rulesTemperature / pressure gauge Boiler bypass requirementsFilling the system Water treatmentConnecting to electrical supply Electrical connectionsAMP Draw Data VACBurners Terminal strip connection optionsTemperature adjustment Locating the temperature controlTemperature control settings OJ1 OJ2Outdoor reset option Temperature control sensors Remote sensor for pump delayPlacement of sensors Boiler applicationRemote Wire Connection Wire Gauge Max. Allowable Length Hot surface ignition systemRemote mounting of a sensor Hot surface igniter and ignition control moduleDiagnostic Status Indication Ignition and control timingsOperation and diagnostic lights Sequence Constant IgnitionStage 2 on SixStartup OFFFreeze protection when used Check/control water chemistryFill and test water system Purge air from water systemCheck for gas leaks Check thermostat circuitsCheck vent and air piping Start the boilerDomestic water heaters Water velocity controlInitial set-up of maximum water flow Maximum Water Flow1Typical water heater piping with storage tank 2Single water heater piping with two storage tanks Common Manifold Size Min Models 497 Number of Units4Multiple water heater piping with multiple storage tanks Required temperature rise Pipe Sizing Chart 497 987Pipe size requirements Water chemistryPotable hot water temperature control settings Domestic water temperatureMinimum pump performance Heat exchangerLocation of cold water supply piping connections High water temperature limit control Optional relief valveThermal expansion Cathodic protectionMaintenance Combustion and ventilation air Adjustment procedure Models 497 Sequence of operation Servicing a hot surface igniter and ignition moduleIgnition system checkout OverviewHeat transfer process End of sequenceGlossary Pump Delay Electronic Thermostat Function Trial for Ignition Ignition Module FunctionIgniter Controlled by Ignition Module Hi-Lo Fire RelayDiagrams Ladder diagramDiagrams Connection diagram Connection diagram

497 - 2067 specifications

Lochinvar 497 - 2067 is a highly efficient and versatile condensing boiler that is designed to meet the diverse heating needs of residential and commercial applications. Known for its impressive performance and advanced technology, the Lochinvar 497 - 2067 has garnered a reputation as a reliable choice among heating professionals.

One of the standout features of the Lochinvar 497 - 2067 is its impressive thermal efficiency. The boiler boasts an efficiency rating of up to 95% AFUE (Annual Fuel Utilization Efficiency), allowing users to significantly reduce their energy costs while minimizing environmental impact. This efficiency is facilitated by its innovative condensing technology, which captures and reuses heat from exhaust gases for optimal performance.

The Lochinvar 497 - 2067 is equipped with a robust stainless steel heat exchanger designed to handle high temperatures and ensure long-lasting performance. The heat exchanger’s design maximizes heat transfer, while its corrosion-resistant properties guarantee durability over time. This contributes to the boiler's overall longevity and serviceability, reducing the need for frequent replacements.

Control is another critical feature of the Lochinvar 497 - 2067. The boiler comes with an advanced control system that enables easy management of system operations. Users can take advantage of features such as outdoor reset control, which adjusts the temperature of the boiler based on external weather conditions, enhancing system efficiency and comfort.

In terms of safety, the Lochinvar 497 - 2067 incorporates several cutting-edge safety features, including a flame detection system and multiple safety shut-off devices. These safeguards help to ensure the safe operation of the boiler, providing peace of mind to users and heating professionals alike.

Another important characteristic is the compact design of the Lochinvar 497 - 2067, which allows for flexible installation in various settings, including tight spaces. Its lightweight structure further simplifies the installation process, making it a practical choice for contractors.

In summary, the Lochinvar 497 - 2067 is an exceptional high-efficiency condensing boiler that combines advanced technology, durability, and ease of use. With its impressive thermal efficiency, superior heat exchanger design, advanced control systems, and enhanced safety measures, it stands out as a top choice for those seeking reliable heating solutions. This boiler not only meets but exceeds modern demands for energy efficiency and performance, solidifying its position in the market.