Lochinvar 45000 Full Flow Application, Low Temperature Bypass Requirements, Boiler Flow Rates

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Installation & Service Manual

4Water connections

Primary/Secondary Boiler Piping (continued)

A primary/secondary piping system is ideal for systems filled with a propylene glycol and water mixture. A glycol and water mixture is more dense than water only and may result in a lower boiler flow rate. A lower boiler flow may cause noisy operation or short cycling of the burners. A larger secondary pump may be used on a primary/secondary system to provide an increased boiler flow rate. A glycol and water system may require from 10 to 20% more flow to compensate for the increased density of the glycol and its effect on the heat transfer process in the boiler. The exact increase in flow that may be required is based on the type and percentage of glycol added to the boiler system. Consult the manufacturer of the glycol for additional recommendations when using a glycol and water fill for your boiler system.

The installer must ensure that the boiler has adequate flow without excessive temperature rise. The temperature rise on a multiple zone system should be made when only the zone with the longest length and/or highest head loss is open. Low system flow can result in overheating of the boiler water which can cause short burner on cycles, system noise and in extreme cases, a knocking flash to steam. System noise may also indicate an oversized boiler.

CAUTION

At no time should the system pressure be

less than 12 PSIG.

 

A boiler operated with an inlet temperature of less than 140°F (60°C) must have a bypass to prevent problems with condensation. A bypass as shown in FIG. 4-5 (see page 33) must be piped into the system at the time of installation.

Full Flow Application

It is acceptable for the Solution boiler to be installed in a full flow application, as long as the following requirements are met:

1.The performance loop is in place and functional.

2.The system flow is not lower than the minimum boiler flow.

3.The boiler setpoint is 140°F or higher.

4.If water temperature is below 140°F you must install a low temperature bypass, VAL30000, and follow the piping diagram shown in FIG. 4-8.

WARNING Varying the flow through a Solution boiler can cause harmonic noises and high limit

trips if the flow is below the minimum boiler flow rate found in Table 4A.

Low Temperature Bypass Requirements

Inlet water temperatures below 140°F (60°C) can excessively cool the products of combustion resulting in condensation on the heat exchanger and in the flue. Condensation can cause operational problems, bad combustion, sooting, flue gas spillage and reduced service life of the vent system and related components. The bypass allows part of the boiler discharge water to be mixed with the cooler boiler return water to increase the boiler inlet temperature above 140°F (60°C). This should prevent the products of combustion from condensing in most installations. The bypass should be fully sized with a balancing valve to allow for proper adjustment. A valve must also be provided on the boiler discharge, after the bypass. Closing this discharge valve forces water through the bypass. Start boiler adjustment with the bypass valve in the full open position and the boiler discharge valve half open. A small amount of the higher temperature boiler discharge water is mixed with the system water to maintain the desired lower system temperature.

Boiler Flow Rates

CAUTION The maximum flow rate through the boiler with a copper heat exchanger must not

exceed 30 GPM.

The heat exchanger is generally capable of operating within the flow rates of a residential heating system. Should the flow rate exceed the maximum allowable flow rate through the boiler 30 GPM) an external bypass must be installed. The bypass should be fully sized with a balancing valve to allow for proper adjustment of flow. Flow rate can be determined by measuring the temperature rise through the boiler.

The basic guide for minimum flow in this boiler is based on a 40°F temperature rise in most installations. Lower flow and a higher temperature rise is acceptable if the boiler system is specifically designed for the characteristics of a higher temperature rise. A system not specifically designed for a higher temperature rise may experience overheating of the boiler water. This can cause short burner on cycles, system noise and in extreme cases, a knocking flash to steam. These conditions can lead to operational problems and non-warrantable failures of the boiler. High temperature rise systems must be designed by a qualified engineer.

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Contents Models 45,000 260,000 Btu/hr Contents Warranty Please read before proceedingCodes Solution Boiler =B=R Rating RatingsSolution How it works Temperature and pressure gaugeSolution How it works Solution How it works Determine boiler location Location of unit3Combustion Air Direct from Outside 6Combustion Air from Outside Single Opening Minimum Recommended Combustion AIR Supply to Equipment Room Conventional Negative Draft Venting System VentingVent Pipe Sizes Venting Vertical Vent Termination Clearances Less from Ridge From Parapet WallMasonry Chimney Installation Sidewall Venting Negative DraftVent Materials Fan Assisted VentingAutomatic Vent Damper 7Vent Damper and Vent Damper Terminal BlockGas Supply Gas Pressure Test Gas connectionsGas Connection Install Piping to Control Gas PipingGas Manifold Pressure Adjustment Procedure 2WrenchChecking Gas Supply Pressure 4Gas Supply PressureVenting of Combination Gas Valves Combination Gas ValvesTwo Stage Burner Control System Water connections Water Flow Switch if equippedRelief Valve Typical Heating Boiler Installations Low Water Cutoff if equippedMinimum Required Flow For Heating Boiler General Plumbing RulesSystem Temperature Rise Chart Piping of the Boiler SystemWater Connections Heat Exchanger Pressure Drop ChartCirculator Pump Requirements Primary/Secondary Boiler Piping Circulator Pump SpecificationsCirculator Pump Operation Full Flow Application Low Temperature Bypass RequirementsBoiler Flow Rates Primary / Secondary Piping Make UP WaterMake UP Water 6Multiple Boilers Zoned with Circulators Full System Flow From System8Single Boiler Full System Flow with Low Temperature Bypass Terminal Strip Wiring Boiler Operating Temperature ControlElectrical connections Auxiliary Device Connection to Terminal StripTemperature Adjustment AMP Draw DataMaximum SET Point Determination Maximum Set Point DeterminationWiring of Remote Sensors Outdoor Air Temperature SensorInstallation of Remote Sensors Outdoor Air Reset Option Additional Temperature ControlsBlocked Vent and Flame Roll-Out / Flame Interlock Switch 7Blocked Vent Switch LocationPre-start Checklist Start-upInitial Start-up Lighting Instructions for Spark Ignition Pilot ModelsOperating Instructions Safety Shutoff Test for Spark Ignition Pilot SystemTo Turn Off Gas to Appliance Intermittent Pilot Spark Ignition System Freeze ProtectionWater Treatment Ignition and Control TimingsMaintenance Maintenance and annual startup Service technicianOwner maintenance See the User’s Information Manual for instructionsMaintenance Check Expansion Tank Check Relief ValveCheck All Wiring Check Control SettingsHeat Exchanger / Burner Access Perform Start-up and ChecksInspection and Cleaning Breathing Fresh airReview with owner Inspection of Heat Exchanger WaterwaysGas Train and Controls Water Circulating PumpTroubleshooting Troubleshooting Guide M9 Solution BoilersDiagrams Schematic Diagram M9 UnitWiring Diagram M9 Unit 45,000 260,000 Btu/hr Models 45,000 260,000 Btu/hr Models
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