Smith Cast Iron Boilers GS110W Operational Sequence, Thermostat Installation, Control Outputs

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GS110 DIRECT VENT BOILER INSTALLATION AND OPERATION INSTRUCTIONS

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installed in Canada. Install a separate 120 volt 15 amp circuit for the boiler. A properly rated shut-off switch should be located at the boiler. The boiler must be grounded in accordance with the authority having jurisdiction, or if none, the latest revision of the National Electrical Code, ANSI/NFPA-70.

Line voltage field wiring of any controls or other devices must use copper conductors with a minimum size of #14 awg. Low voltage wiring must not be less than #18 awg with a neoprene, thermoplastic or other equivalent insulation having a minimum insulation thickness of 0.012 inches.

Refer to Figures 19A and 19B for proper wiring connections.

Thermostat Installation

ALWAYS follow the instructions included with the ther- mostat to be used to control the boiler. Proper location of the thermostat will ensure efficient trouble-free operation of the boiler. Mount the thermostat to an inside wall at a height approximately five feet above the floor. Avoid placing the thermostat in areas that will not pro- vide an accurate measurement of the room temperature. Locating the thermostat behind a door, in an alcove, close to a source of thermal radiation or in a drafty area will cause poor or sporadic heating.

OPERATIONAL SEQUENCE

The control energizes the circulator motor when the thermostat contacts are closed. The control then checks that the limit switch is closed, if not the control will wait for the limit switch to close. With the limit switch closed the pressure switch contacts are checked. If the pressure switch contacts are open the blower motor is energized. If the pressure switch contacts aren’t open the control will wait 45 seconds then lock out. The PURGE light will flash to indicate a pressure switch fault. Also, if the pressure switch does not close within 5 minutes of the blower being turned on, the control will lock out with the PURGE light flashing to indicate a pressure switch fault.

The pre-purge period begins when the pressure switch contacts close. At the end of the pre-purge period, the control energizes the HSI igniter for an HSI warm-up period. This condition will be indicated by illumination of the IGNITER light. A one second trial for ignition will take place. In the event ignition is not achieved by the end of the first trial for ignition period, the control will run through a post purge and then de-energize the inducer. When the pressure switch contacts open the control will begin a new ignition sequence. Failure to establish flame after the third attempt will result in ignition lock-out and the VALVE light on the control will flash.

Once the flame has been proven, the system is in Steady-State heating mode. The control will continuously monitor the thermostat, limit switch, pressure switch, and flame sense. If the thermostat opens, the control will de-energize the gas valve and begin post-purge. If the limit switch opens, the control will de-energizes the gas valve, run through post-purge, and wait for the limit switch to re-close before attempting re-ignition. If flame is lost, the control will de-energize the gas valve, run through post-purge, and go to pressure switch proving mode for re-ignition. If the pressure switch opens for more than 0.1 seconds the inducer is turned off for 30 seconds, then the control goes to the pressure switch proving mode for a re-ignition attempt.

When the thermostat is satisfied the post purge period starts. A post-purge will be performed at any time the gas valve has been on and is turned off, except for loss of pressure switch, when a post-purge would be ineffective. The post-purge must be completed before a new ignition sequence can start.

In the event that the flame signal is lost after the flame has been proven, the system will turn off the gas valve within 2.0 seconds, perform the post-purge, and repeat the ignition sequence. As a preventative measure to avoid nuisance shutdown due to a flickering flame, the flame must be lost for a minimum of 0.5 seconds.

Control Outputs:

Induced draft blower - 1.75 Amps @ 120 VAC.

Circulator Pump - 2.7 Amps @ 120 VAC.

Hot Surface Igniter - 5.0 Amp resistive @ 120 VAC.

Gas Valve - 0.6 Amp @ 24 VAC, 0.45 power factor.

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Contents GS110W Before YOU Start ContentsBoiler Location Boiler Ratings & CapacitiesAll Combustion Air From Inside The Building Combustion AIR & VentilationDuct Size Combustion Air Duct SizingNumber Combustion Air System SizingIntake Air Optional Horizontal Guidelines Intake Air Option Vertical GuidelinesSmith Page Horizontal Direct Vent Systems General Venting GuidelinesGeneral Direct Vent Info Vent System OptionsCertified Vent Terminals Vertical Direct Vent SystemsHorizontal Vent Positive Pressure Systems Certified Vent & Intake TerminalsEquivalent Breeching & Chimney Size Vertical Vent Positive Pressure SystemsVertical Vent Negative Pressure Systems Chimney Inspection & SizingVertical Positive Pressure Venting Cat Common Vent Systems Condensate Piping Boiler Water VolumeHeating System Piping System Bypass Bypass PipingPump Away Bypass Circulators Piping For Use With Cooling UnitsGas Pipe Capacity Equivalent Pipe Length ChartWhen servicing controls. Wiring errors can cause GAS Supply PipingOperational Sequence Thermostat InstallationControl Outputs Wiring Connection Diagram Wiring Ladder Diagram For Your Safety Read Before Operating Pour Votre Sécurité Lisez Avant DE Mettre EN Marche Boiler Operation Boiler SET UPDirect Ignition System Air and Manifold Pressure Boiler Checking & AdjustmentBoiler Maintenance Instructions to the Installer Page Model Size with Item Quantities Below Ref # Name of Part Service and Replacement Parts ListModel Size with Item Quantities Below Page North ELM Street WESTFIELD, MA 01085 TEL 562-9631 FAX 413

GS110W specifications

The Smith Cast Iron Boilers GS110W stands as a premier choice for those seeking efficiency and reliability in heating systems. Known for their robust construction and advanced engineering, Smith Boilers are designed to meet the needs of both residential and commercial applications. The GS110W model showcases an impressive blend of performance and durability, making it a favorite among HVAC professionals and end users alike.

One of the main features of the GS110W is its cast iron construction. Cast iron is celebrated for its ability to retain heat, allowing the boiler to operate efficiently while providing consistent warmth over extended periods. This material also contributes to the boiler's longevity, allowing it to withstand the rigors of heating without significant wear and tear. The GS110W is designed to last, making it a wise investment for any heating needs.

The GS110W boasts an output capacity of 110,000 BTU/hour, making it suitable for a variety of heating applications. This output enables it to efficiently heat large spaces, whether in a multi-story building or a spacious home. The boiler’s efficiency rating is further enhanced by its ability to use multi-fuel options. It can efficiently burn oil or gas, providing flexibility depending on the availability and cost of fuel.

In terms of technology, the GS110W incorporates advanced boiler design that includes a submerged combustion chamber. This engineering feature allows for superior heat transfer while minimizing heat loss, ensuring that the maximum amount of energy is utilized for heating. Additionally, the boiler features a low water cutoff to enhance safety, preventing potential overheating and system failures.

Reliability is further ensured through the GS110W’s built-in controls and adjustments. The boiler is equipped with a digital aquastat that allows for precise temperature management, ensuring optimal performance. This user-friendly feature makes it easier for homeowners and technicians to monitor system conditions and make necessary adjustments for peak efficiency.

Another noteworthy characteristic of the Smith Cast Iron Boilers GS110W is its low emissions output. As environmental considerations become increasingly important, the GS110W is designed to minimize its environmental impact while still delivering powerful heating capabilities.

In conclusion, the Smith Cast Iron Boilers GS110W offers an outstanding combination of durability, efficiency, and advanced technology. Its robust cast iron construction, multi-fuel capability, and innovative design features make it a top choice for anyone looking to enhance their heating system. For those in search of reliable and efficient heating solutions, the GS110W stands out as a formidable contender.
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