Pressure Drop in Feet of Head Feedwater Regulator

Raypak recommends that a feedwater regulator be in- stalled and set at 12 psi minimum pressure at the highest point of the system. Install a check valve or back flow device upstream of the regulator, with a manual shut-off valve as required by local codes.

Piping

All high points should be vented. Purge valves and a bypass valve should be installed. A heater installed above radiation level must be provided with a low wa- ter cut-off device (sales order option F-10). The heater, when used in connection with a refrigeration system, must be installed so that the chilled medium is piped in parallel with the heater with appropriate valves to pre- vent the chilled medium from entering the heater.

The piping system of a hot water heater connected to heating coils located in air handling units where they may be exposed to circulating refrigerated air, must be equipped with flow control valves or other automatic means to prevent gravity circulation of the heater water during the cooling cycle. It is highly recommend- ed that the piping be insulated.

Air-Separation/Expansion Tank

All heaters should be equipped with a properly sized expansion tank and air separator fitting as shown in Fig. 10.

heaters which are not subject to thermal shock. Raypak offers a full line of electronic sequencers that produce direct reset of heater water temperature.

(Refer to the Controls section of the Raypak Catalog.)

NOTE: BYPASS FOR

LOW TEMP SYSTEMS ONLY

SYSTEM SENSOR

(HEAT PUMP)

5’ MAX

SYSTEM SENSOR

(4:1 TURNDOWN 5’ MAX

OR GREATER)12” MAX

OR MIN FEASIBLE

Fig. 11: Single Heater - For Hydronic or Heat Pump

Primary/Secondary Piping

 

 

SYSTEM SENSOR

 

 

(LESS THAN

 

 

4:1 TURNDOWN)

 

 

5’ MAX

 

5’ MAX

12” MAX

SYSTEM SENSOR

 

OR MIN FEASIBLE

(4:1 TURNDOWN

 

 

OR GREATER)

 

 

Fig. 10: Air-Separation/Expansion Tank

Three-Way Valves

Valves designed to blend water temperatures or reduce water circulation through the heater should not be used. Raypak heaters are high-recovery, low-mass

Fig. 12: Dual Heaters (Reverse/Return)

with Primary/Secondary Piping

Domestic Hot Water

When designing the water piping system for domestic hot water applications, water hardness should be con- sidered. Table I indicates the suggested flow rates for soft, medium and hard water. Water hardness is ex- pressed in grains per gallon.

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Raypak 302B Pressure Drop in Feet of Head Feedwater Regulator, Piping, Air-Separation/Expansion Tank, Three-Way Valves
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302B, 902B specifications

Raypak is a prominent name in the heating industry, particularly known for its advanced technology and robust design in residential and commercial heating solutions. Two of their notable models, the Raypak 302B and 402B, exemplify innovation and efficiency in hydronic heating systems, designed to meet diverse needs while ensuring optimal performance.

The Raypak 302B and 402B are high-efficiency boilers that utilize gas-fueled systems. The 302B model has a heating capacity of 302,000 BTU/h, while the 402B boasts a maximum capacity of 402,000 BTU/h. This range of heating output makes these models suitable for a variety of applications, from residential heating needs to larger commercial spaces that require a reliable heat source.

One of the standout features of the Raypak 302B and 402B is their use of fire-tube heat exchanger technology. This design promotes efficient heat transfer and allows for lower emissions, thus minimizing the environmental impact. The fire-tube design also contributes to a longer lifespan and reduced maintenance costs, making these boilers a cost-effective solution over time.

Equipped with advanced control systems, the Raypak 302B and 402B ensure precise temperature regulation and improved energy usage. The digital display provides real-time feedback and diagnostics, enhancing user experience and simplifying troubleshooting. These models are also compatible with various building management systems, providing users with versatility in integration to optimize building performance.

In addition to their technological advancements, these boilers are designed with user safety and convenience in mind. They include features such as built-in safety controls, easy access for service and maintenance, and a compact footprint to fit into tight spaces. Their robust construction ensures durability, which is crucial for systems that operate under high demand.

Moreover, both models have been engineered to succeed in various climates, making them reliable choices for users in diverse geographical locations. With their energy-efficient operation, reliable performance, and advanced features, the Raypak 302B and 402B embody quality and innovation in the heating market, ensuring comfortable environments while lowering energy costs and environmental footprints.
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