Lochinvar 497 - 2067 service manual Combination gas valves, Venting of combination gas valves

Page 24

Installation & Service Manual

3 Gas connections

Combination gas valves

These units fire in multiple stages of burner input. Each stage of burner operation has a combination gas valve(s) to cycle the gas supply on and off and regulate gas to the burners. Each combination valve consists of a gas regulator and two valve seats to meet the requirements for redundant gas valves. The valve has a gas control knob that must remain in the open position at all times when the unit is in service. The gas control valve has pressure taps located on the inlet and discharge sides of the valve. Manifold pressure is adjusted using the regulator located on the valve. A manifold gas pressure tap for each burner stick is located on the discharge side of the valve. The manifold pressure is preset at the factory and adjustment is not usually required. If you must adjust regulator pressure, follow the instructions under Gas Manifold Pressure Adjustment, page 25.

Venting of combination gas valves

The combination gas valve/regulator used on all units is equipped with an integral vent limiting orifice per ANSI Z21.78. The vent limiter ensures that the volume of gas emitted from the valve in the event of a failed gas diaphragm does not exceed the maximum safe leakage rate allowed by agency requirements.

Combination gas valve/regulators equipped with integral vent limiters are not required to have vent or relief lines piped to the outdoors. The termination of the vent limited opening on the combination gas valve/regulator complies with the safety code requirements of CSD-1, CF-190(a) as shipped from the appliance manufacturer without the installation of additional vent lines.

Checking gas supply pressure

Use the following procedure to check gas supply pressure.

1.Turn the main power switch to the “OFF” position.

2.Turn gas valve knobs to the “OFF” position.

3.Shut off gas supply at the field-installed manual gas cock in the gas piping to the unit. If fuel supply is L.P. gas, shut off gas supply at the tank.

4.Remove the 1/8'' hex plug, located on the “inlet” side of the gas valve (FIG. 3-3). You may also use a tapping on the field-installed main manual gas cock or gas piping. Install a fitting in the inlet pressure tapping suitable to connect to a manometer or magnehelic gauge. Range of scale should be 14'' w.c. or greater to check inlet pressure.

5.Turn on gas supply at the manual gas cock, turn on L.P. gas at the tank if required.

6.Turn the power switch to the “ON” position.

7.Turn the gas valve knobs to the “ON” position. Set the electronic temperature control or thermostat to call for heat.

8.Observe the gas supply pressure as all burners are firing. Ensure that inlet pressure is within the specified range. See Connecting To Gas Supply, page 22 for minimum and maximum gas supply pressures.

9.If gas pressure is out of range, contact gas utility, gas supplier, qualified installer or service agency to determine necessary steps to provide proper gas pressure to the control.

TABLE 3D

GAS PIPING SIZE CHART

Nominal

 

 

 

 

Length of Pipe in Straight Feet

 

 

 

 

 

Maximum

Iron Pipe

 

 

 

 

 

 

 

 

 

Capacity of Pipe

Size

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

in Thousands of

Inches

10

20

30

40

50

60

70

80

90

 

100

125

150

175

200

Btu/hr per hour

3/4

369

256

205

174

155

141

128

121

113

 

106

95

86

79

74

for gas pressures

 

of 14 Inches

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

697

477

384

328

292

267

246

256

210

 

200

179

164

149

138

Water Column

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(0.5 PSIG) or less

1 1/4

1,400

974

789

677

595

543

502

472

441

 

410

369

333

308

287

 

and a pressure

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1 1/2

2,150

1,500

1,210

1,020

923

830

769

707

666

 

636

564

513

472

441

drop of 0.5 Inch

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Water Column

2

4,100

2,820

2,260

1,950

1,720

1,560

1,440

1,330

1,250

 

1,180

1,100

974

871

820

 

(Based on NAT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2 1/2

6,460

4,460

3,610

3,100

2,720

2,460

2,310

2,100

2,000

 

1,900

1,700

1,540

1,400

1,300

 

GAS, 1025 Btu/hr

3

11,200

7,900

6,400

5,400

4,870

4,410

4,000

3,800

3,540

 

3,300

3,000

2,720

2,500

2,340

per Cubic Foot

 

of Gas and 0.60

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

23,500

16,100

13,100

11,100

10,000

9,000

8,300

7,690

7,380

 

6,870

6,150

5,640

5,130

4,720

 

Specific Gravity)

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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.

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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.

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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.
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