Table of Contents

Codes . . . . . . . . . . . . . . . . . . . . . . . . .2

Combustion & Ventilation Air . . . . . . . . .5

Contaminants . . . . . . . . . . . . . . . . . . . .6

Determining Total “Free Area” . . . . . . . .5

Electrical Requirements . . . . . . . . . . . .14

Gas Supply . . . . . . . . . . . . . . . . . . . .10

General Venting . . . . . . . . . . . . . . . . . .6

Location of Unit . . . . . . . . . . . . . . . . . .2

Low Water Temperature Delivery . . . . .12

Outdoor Use . . . . . . . . . . . . . . . . . . . .3

Outdoor Installation . . . . . . . . . . . . . . .9

Pump Operation . . . . . . . . . . . . . . . . .12

Relief Valve . . . . . . . . . . . . . . . . . . . .14

Venting Options . . . . . . . . . . . . . . . . . .8

Water Connections . . . . . . . . . . . . . . .11

Water Treatment . . . . . . . . . . . . . . . . .13

Water Velocity Control . . . . . . . . . . . .12

Figures & Tables Index

FIG. 1 Models CW 495-2066

Requirements For Installation

Over Combustible Floor . . . . .3

FIG. 2 Water Heater Equipment

& Control Orientation . . . . . . .4

FIG. 3-6 Combustion &

Ventilation Air . . . . . . . . . . .5,6

FIG. 7 Barometric Damper

Installation . . . . . . . . . . . . . . .8

FIG. 8 Multiple Unit Barometric

Damper Installation . . . . . . . .9

FIG. 9 Outdoor Venting . . . . . . . . . . .9

TABLE A. Clearances From

Combustible . . . . . . . . . . . . .3

TABLE B. Flue Sizes . . . . . . . . . . . . . . . .8

TABLE C. Outdoor Kits . . . . . . . . . . . .10

TABLE D. Gas Supply Pipe Sizing . . . .11

TABLE E. Inlet Gas Pressure . . . . . . . . .11

TABLE F. Required Temperature Rise . . .12

TABLE G. Required Pump Performance .13

TABLE H. Common Water

Manifold Sizes . . . . . . . . . . .14

TABLE I. Amp Draw . . . . . . . . . . . . . .14

Appendix A -

Water Heater Piping Diagrams

Single Heater – Single Tank . . . . . . . . .A1

Single Heater – Two Tanks . . . . . . . . .A2

Two Temperature Installation

Single Heater – Single Tank . . . . . . . . .A3

Two Heaters – Single Tank . . . . . . . . .A4

Two Heaters – Two Tanks . . . . . . . . . .A5

Multi-Stack Frame

Two Heaters – Single Tank . . . . . . . . .A6

L o c h i n v a r D E S I G N E R ’ S G U I D E C O P P E R - F I N W A T E R H E A T E R 6 1 5 - 8 8 9 - 8 9 0 0	1

CW 645, CW 745 specifications

The Lochinvar CW 645 and CW 745 are advanced water heater models from Lochinvar, a leading manufacturer of water heating solutions. These high-efficiency units are designed to meet the demands of both commercial and residential applications, combining cutting-edge technology with robust performance.

One of the defining features of the CW series is its commitment to energy efficiency. With their stainless steel construction, these water heaters boast a high thermal efficiency rating. The CW 645 and CW 745 utilize modulating technology, allowing them to adjust the heating output based on real-time demand. This results in reduced energy consumption and lower operational costs, making them an ideal choice for environmentally conscious consumers.

These models are equipped with a powerful burner system designed to provide optimal heating performance. The burners are engineered for reliability and longevity, ensuring consistent hot water supply even under heavy usage. Additionally, the CW 645 and CW 745 feature a compact footprint, making them suitable for installation in tight spaces or areas with limited access.

The advanced control system in these units takes user experience to the next level. With intuitive controls and a digital display, users can easily set temperatures and monitor system performance. The integrated diagnostics feature ensures quick troubleshooting, enhancing reliability and reducing maintenance time.

Safety is another paramount consideration in the design of the CW series. Both models come equipped with multiple safety features, including a flame safeguard system and a high-temperature limit switch. These safety mechanisms provide peace of mind while ensuring compliance with local building codes.

Furthermore, the CW 645 and CW 745 models are versatile in their applicability. They can be used for a variety of applications including restaurants, schools, and hospitals. Their ability to provide consistent hot water makes them particularly valuable in high-demand situations.

In summary, the Lochinvar CW 645 and CW 745 are exceptional water heating solutions that epitomize efficiency, safety, and performance. With advanced features, user-friendly controls, and solid construction, these units are well-suited to meet the hot water needs of both commercial and residential users. Investing in a CW series water heater not only secures a reliable source of hot water but also contributes to long-term energy savings and environmental sustainability.

Lochinvar CW 645, CW 745 manual Table of Contents

Models: CW 645 CW 745