Lochinvar 497 - 2067 service manual Outdoor reset option

Page 40

Installation & Service Manual

5 Electrical connections

Setpoint

The Set Point knob specifies the target water temperature in degrees, Fahrenheit. After the water temperature reaches the set point, the temperature control shuts off the burners.

Differential

The Differential specifies the number of degrees below the set point that the control will allow the water temperature to drop before it brings the unit back on again.

High-fire offset

The temperature control operates a two-stage firing system. The two stages are High-Fire and Low-Fire. High-Fire operates all burners while Low-Fire operates approximately one-half of the burners.

The High-Fire knob specifies the number of degrees below set point that the High-Fire stage shuts down. At that point, the unit will continue to operate at the Low-Fire stage until the set point is reached.

The High-Fire offset knob has settings between 0°F and 20°F. If set at 0°F, the High-Fire offset is disabled and the unit will operate at the High-Fire stage until the set point is reached and the temperature control shuts the unit off.

When the High-Fire offset knob is set to 0 or 1, the unit will light at Low Fire and operate for approximately 10 seconds before the High-Fire stage actuates. When set to 2 or above, the unit will operate at Low Fire for 2 minutes before the High Fire stage can actuate.

Figure 5-8_Optional outdoor reset control

OUTDOOR

OUTDOOR

AIR

AIR

SHUTDOWN

SENSOR

SHUTDOWN

 

OUTDOOR

RATIO

AIR

 

MAX

 

40

 

Outdoor reset option

For boilers ordered with the Outdoor Air Reset option, there is an additional control (see FIG. 5-8). There are three setting knobs for Shutdown, Outdoor Air Max., and Ratio. There is also a switch to turn the outdoor air sensor On or Off. An O.A. Sensor is also included.

Shutdown

The Shutdown knob specifies the outdoor air shutdown temperature at which the control would prevent the unit from operating. This feature can be enabled/disabled with the O.A. Shutdown switch.

Outdoor air max (O. A. Max)

The O. A. Max knob allows a reset up to the maximum outdoor air temperature specified by this knob setting. When the outdoor air temperature is above the specified setting, the unit will not function in the O.A. Reset Mode, but will continue to run at the selected set point temperature.

Note that the set point knob will now indicate the “minimum” boiler temperature. Target temperature is determined by the ratio and outdoor air temperature below the O.A. Max setting.

Ratio

The Ratio knob allows the control over the reset ratio to be used during Outdoor Air Reset. The allowable ratios are as low as 0.5:1 or as high as 1.5:1.

Selecting the 0.5:1 ratio will increase the set point 0.5°F for every 1.0°F drop in outdoor air temperature up to the maximum set point temperature.

Selecting the 1.5:1 ratio will increase the set point 1.5°F for every 1.0°F drop in outdoor air temperature up to the maximum set point temperature (see page 39).

See FIG. 5-10 for an outdoor air reset chart example.

Page 39 Page 41
Image 40
Page 39 Page 41
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 filterCombustion Air Options Outside Combustion Air, Using DuctsOutside Combustion Air, No Ducts Exhaust Fans Combustion Air from an Interior SpaceVenting General informationVenting support Vertical vent termination clearances and locationBarometric damper location Vent system optionsFlue 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 Water connections heating boilers only Pressure Drop ChartBoiler circulator requirements Low system water volume Minimum boiler water temperaturesRun 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.
Top Page Image Contents