Lochinvar 497 - 2067 service manual Minimum boiler water temperatures, Low system water volume

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4 Water connections (continued)

Pump Maintenance: Inspect the pump every six (6) months and oil as necessary. Use SAE 30 non-detergent oil or lubricant specified by the pump manufacturer.

The boiler is recommended for installation in a primary/ secondary piping system. This type of system uses a separate boiler circulating pump to supply flow to and from the boiler only. The secondary pump is sized based on the head loss of the boiler and related pipe and fittings in the secondary loop only.

A properly sized primary system pump provides adequate flow to carry the heated boiler water to radiation, air over coils, etc. The fittings that connect the boiler to the primary system should be installed a maximum of 12 inches (0.30m) (or 4 pipe diameters) apart to ensure connection at a point of zero pressure drop in the primary system. There should be a minimum of 10 pipe diameters of straight pipe before and after the boiler secondary loop connections to prevent turbulent flow at the secondary loop connections. The secondary loop piping to and from the boiler must have a fully ported ball valve installed in both the supply and return side piping. The ball valves must be fully ported having the same inside diameter as the installed piping. The ball valve in the piping supplying water to the boiler will only be used as a service valve. The ball valve installed in the discharge from the boiler back to the primary system will be used to adjust boiler flow and temperature rise to ensure proper performance.

The boiler primary piping system must have a circulator installed in the main system loop to carry the heated boiler water to the point of use in the main system.

Multiple boilers may also be installed with a primary/secondary manifold system. Multiple boilers should be connected to the common manifold in reverse return to assist in balancing flow to multiple boilers.

The installer must ensure that the boiler has adequate flow without excessive temperature rise. Low system flow can result in overheating of the boiler water which can cause short burner cycles, system noise, relief valve discharge and in extreme cases, a knocking flash to steam. These conditions indicate the need to increase boiler flow to and from the boiler. This is generally accomplished by either increasing the size of the boiler pump or by increasing the diameter of the piping that connects the boiler to the primary system. A larger diameter pipe reduces head loss and increases flow.

CAUTION

At no time should the system pressure be less

 

than 12 PSIG.

 

Do not allow the flow in the primary loop

CAUTION

 

to drop lower than the flow in the secondary

 

 

loop at any time during boiler operation.

 

Improper operation of the boiler(s) and

 

possible tripping of the high limits and relief

 

valves may occur.

Installation & Service Manual

Minimum boiler water temperatures

Inlet water temperatures below the specified minimum of 140°F (60°C) can excessively cool the products of combustion resulting in condensation on the heat exchanger. Condensation on the heat exchanger can cause operational problems, bad combustion, sooting, flue gas spillage and reduced service life of the related components. See the Low Temperature Bypass Requirements section for boiler system applications below the minimum specified temperature.

Low system water volume

System run time is very important to the overall operating efficiency of the boiler. Short cycling of the boiler creates problems with condensation in the vent stack, condensation on the heat exchanger, system temperature spikes, and mechanical component failures. To prevent short cycling of the boiler, it is important to limit the boiler cycles to six or fewer per hour.

A buffer tank is an effective way to enhance a small system load and increase heating system efficiency (see FIG. 4-8 on page 34 of this manual). Buffer tanks add water volume to the system and act as a flywheel to absorb the additional Btu’s provided by the boiler when only a single zone of a large system is calling for heat.

To calculate the proper buffer tank size for a multiple zone system:

(Run Cycle) (Output - Minimum System Load)

(Temp. Rise) (8.33) (60 Min.)

CFN2067

Min. Load = 100,000 Btu/Hr

Min. Boiler Output = 850,000 Btu/Hr

Cycle Time = 10 Min

Temp. Rise = 38

(10)(850,000 – 100,000) / (38)(8.33)(60) = 395 Gallons

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Contents Save this manual for future reference What to do if YOU Smell GASContents Please read before proceeding WarrantySpecial instructions Checking equipmentOwner warning Safety informationPrevention of freezing CodesCopper-fin How it works Copper-fin How it works Models 987 2067 Front View Models 987 2067 Rear View Copper-fin =B=R Rating RatingsCopper-fin Specifications Determine unit location InstallationLocating the unit Indoor clearances from combustible constructionShut-down and draining Outdoor boiler installationFreeze protection Pump operationCombustion and Ventilation Air Freeze Protection for a Heating Boiler System if requiredMinimum Recommended Combustion AIR Supply to Equipment Room NumberCombustion air filter 3Combustion air filter Models 497Outside Combustion Air, No Ducts Outside Combustion Air, Using DuctsCombustion Air Options Combustion Air from an Interior Space Exhaust FansGeneral information VentingVenting support Vertical vent termination clearances and locationFlue Pipe Sizes Model Flue Size Vent system optionsBarometric damper location Negative draft Conventional negative draft ventingFlue outlet piping Common venting systemsInspection of a masonry chimney Masonry chimney installationOutdoor vent/air inlet location Outdoor installation ventingOutdoor Vent Kits Model Pump Cover Without Pump Cover Outdoor vent kitGas connections Connecting to gas supply Gas pipingGas pressure test Inlet GAS Pressure Natural ModelGas connection Suggested GAS Pipe Size for Single Unit InstallationsGas train and controls Fittings to Equivalent Straight PipeCombination gas valves GAS Piping Size ChartVenting of combination gas valves Checking gas supply pressure3Measuring gas supply pressure at combination gas valve Gas manifold pressure adjustmentNat. Gas 4Measuring manifold gas pressureWater connections Boiler circulator requirements Pressure Drop ChartWater connections heating boilers only Run Cycle Output Minimum System Load Temp. Rise 8.33 60 Min Minimum boiler water temperaturesLow system water volume System Temperature Rise Chart Low temperature return water systemsRadiant floor and snow melt heating systems LTV Valve Kits Model LTV Valve KITGPM Common Manifold Size Min Models 497 Number of UnitsDiameter 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 Typical heating boiler installations Installation with a chilled water systemBoiler flow rate General plumbing rulesBoiler bypass requirements Temperature / pressure gaugeFilling the system Water treatmentElectrical connections Connecting to electrical supplyAMP Draw Data VACTerminal strip connection options BurnersLocating the temperature control Temperature adjustmentTemperature control settings OJ1 OJ2Outdoor reset option Remote sensor for pump delay Temperature control sensorsPlacement of sensors Boiler applicationHot surface ignition system Remote Wire Connection Wire Gauge Max. Allowable LengthRemote mounting of a sensor Hot surface igniter and ignition control moduleIgnition and control timings Diagnostic Status IndicationSequence Constant Ignition Operation and diagnostic lightsStage 2 on SixOFF StartupCheck/control water chemistry Freeze protection when usedFill and test water system Purge air from water systemCheck thermostat circuits Check for gas leaksCheck vent and air piping Start the boilerWater velocity control Domestic water heatersInitial set-up of maximum water flow Maximum Water Flow1Typical water heater piping with storage tank 2Single water heater piping with two storage tanks Models 497 Number of Units Common Manifold Size Min4Multiple water heater piping with multiple storage tanks Pipe Sizing Chart 497 987 Required temperature risePipe size requirements Water chemistryDomestic water temperature Potable hot water temperature control settingsMinimum pump performance Heat exchangerLocation of cold water supply piping connections Optional relief valve High water temperature limit controlThermal expansion Cathodic protectionMaintenance Combustion and ventilation air Adjustment procedure Models 497 Servicing a hot surface igniter and ignition module Sequence of operationIgnition system checkout OverviewEnd of sequence Heat transfer processGlossary Trial for Ignition Ignition Module Function Pump Delay Electronic Thermostat FunctionIgniter Controlled by Ignition Module Hi-Lo Fire RelayLadder diagram DiagramsDiagrams 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.
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