Crown Boiler TWZ125, TWZ200, TWZ090, TWZ065, TWZ175 Single Zone Wiring, Wiring Variations, 2019

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X Wiring

WARNING

All wiring and grounding must be done in accordance with the authority having jurisdiction or, in the absence of such authority, with the National Electric Code (ANSI/NFPA70).

Single Zone Wiring

1)120 Volt Wiring - The boiler should be provided with its own 15A branch circuit with fused disconnect. All 120 volt connections are made inside the L8148 or L8124 aquastat relay as follows (also see Fig. 19):

•Hot (“black”) - Terminal “L1”

•Neutral (“white”) - Terminal “L2”

•Ground (“green” or bare) - Ground screw on case of L8148 or L8124

2)Thermostat Wiring - Follow thermostat manufacturer instructions. To insure proper thermostat operation, avoid installation in areas of poor air circulation, hot spots (near any heat source or in direct sunlight), cold spots (outside walls, walls adjacent to unheated areas, locations subject to drafts). Provide Class II circuit between thermostat and boiler. Connect thermostat wire leads to terminals “T” and “T” inside L8148 or L8124 aquastat relay.

Wiring Variations

1)Multiple Circulator Zones – Figure 20 shows wiring for two or more circulator zones using Honeywell R845As. One R845A is required for each circulator zone. Circulator terminals “C1” and “C2” on the L8148 are not used. A DPST Honeywell RA832A may be substituted in place of the R845A using the “X” and “X” terminals in place of the “5” and “6” terminals on a R845A.

A call for heat from any thermostat will energize the DPST relay in that zone’s R845A. When this relay is energized, electrical continuity is created between terminals 3 and 4, energizing the circulator for that zone. At the same time, electrical continuity is created between terminals 5 and 6 on the R845A, creating a current path from terminal “T” to “T” on the L8148 or L8124. Assuming that the supply water temperature is below the high limit setting, the normal ignition sequence will be initiated.

2)Multiple Zones using Zone Valves – Figure 21 shows wiring for multiple zones using Honeywell V8043F zone valves. This wiring diagram may be used for other 24-volt zone valves as long as they are equipped with end switches. Do not attempt to use the transformer on the L8148 or L8124 to power the zone valves; use a separate transformer. Up to five V8043Fs may be powered by one 48VA transformer, such as the Honeywell AT87A.

A call for heat from a given thermostat will result in the application of 24 volts across the TH and TR terminals on the corresponding zone valve, energizing the zone valve motor. The zone valve opens and the end switch contacts are then made. The end switches are connected in parallel with each other and to the “T” and “T” thermostat connections so that any zone valve that opens will also start the circulator and fire the boiler (assuming the high limit is not open). Zone valve terminal TH/TR has no internal connection on the zone valve; it is merely a “binding post” used to connect two or more wires.

2019

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Contents TWZ Series Product Description Table of ContentsII Specifications III Before Installing General SpecificationsIV Locating the Boiler Frontview Side View Air for Combustion and Ventilation For Buildings of Other than Unusually Tight ConstructionBoiler Installed in Confined Space ALL AIR from Inside For Buildings of Unusually Tight ConstructionALL AIR from Outdoors Ventilated Crawl Space and Attic ALL AIR from OUTDOORS, Using VI Venting 109Minimum Recommended Breeching Chimneysize 1110VII System Piping StandardPiping1312 Piping for Special Situations 1413Isolation of Boiler from System Viii Tankless Heater Piping 1615IX Fuel Line Piping 17161817 ONE-PIPE Lift System1918 TWO-PIPE Gravity Feed SystemWiring Single Zone WiringWiring Variations 2019Wiring DIAGRAM, Single Heating Zone only XI Start-up and Checkout 22212223 2423 Boiler ModelXII Service and Maintenance 25242625 Avoid Breathing Fiber Particulates and Dust 27262827 KEY # Description QTY. or Quantity PER Boiler or Crown P.NPage 3029 Quantity PER Boiler or Crown P.N3130 PN980270 Rev609/10

TWZ150, TWZ125, TWZ065, TWZ075, TWZ100 specifications

Crown Boiler, known for its solid and reliable heating solutions, has designed the TWZ series to provide effective heating for both residential and commercial applications. The models in this series—TWZ090, TWZ120, TWZ175, TWZ200, and TWZ100—offer varying capacities and features tailored to meet diverse heating needs.

One of the key features of the TWZ series is its efficiency. These boilers are designed with a cast-iron heat exchanger that maximizes thermal efficiency, allowing for optimal heat transfer. This not only helps in reducing energy consumption but also ensures that the home remains warm and comfortable during the colder months. With an annual fuel utilization efficiency (AFUE) rating that can reach up to 85%, users can expect lower energy bills as well.

Each model in the TWZ series is equipped with a durable and robust construction. The cast iron sections provide increased resistance to wear and tear, making the TWZ series a long-lasting solution for heating needs. This is particularly beneficial for users looking for reliability over time, as the longevity of these boilers reduces the need for frequent replacements.

In terms of technology, the TWZ series features advanced controls that enhance functionality and ease of use. These boilers are compatible with various heating control systems, allowing users to fine-tune their heating setup according to their specific requirements. The inclusion of a flame safeguard system further ensures safety during operation, reducing the risk of malfunctions and improving overall reliability.

The TWZ series is designed for easy installation and maintenance. With options for direct venting or conventional chimney venting, homeowners and installers can choose the most suitable configuration for their properties. Additionally, the maintenance access points on these boilers make routine service checks simple and efficient, ensuring that the boilers remain in optimal condition.

Another important characteristic of the Crown Boiler TWZ series is its quiet operation. Advanced engineering minimizes noise production, making these boilers ideal for residential settings where peace and comfort are valuable.

In conclusion, the Crown Boiler TWZ090, TWZ120, TWZ175, TWZ200, and TWZ100 models offer a compelling combination of efficiency, durability, advanced technology, and user-friendly features. Whether for residential or light commercial use, they represent an excellent choice for anyone seeking reliable heating solutions.
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