2.1 Sizing tankless water heaters 2.2 Bosch GWH 715 ES 2.3 Bosch GWH C 800 ES 2.4 Outdoor Installation for GWH 715 ES and GWH C 800 ES 2.5 Bosch GWH 345 ESR 2.6 Bosch GWH 450 ESR 2.7 Bosch GWH 425 EF 2.8 Bosch GWH 425 HN...
1 Introduction The Bosch Applications Manual is intended to present some of the most common applications of the Bosch line of tankless and point of use water heaters. Application drawings are shown with both piping and corresponding electrical schematics where applicable. Auxiliary equipment depicted does not necessarily represent any one manu- facturer or specifi...
Rule of Thumb Sizing Model Number Number of Major Number of Minor Applications Applications GWH 715 ES GWH C 800 ES GWH 425 HN/PN/EF GWH 425 HN/PN/EF GWH 260 PN RP17PT RP27PT Using a known volume container, record several fi ll times. Per- form the calculation below to determine the fl...
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Applications manual GWH C 800 ES GWH C 8 GWH 715 ES GWH 425 PN/HN GWH 425 GWH 260 PN/HN Degree rise (°F) Gas Appliance Sizing Chart RP27PT RP17PT RP17PT RP12PT RP12PT RP7P RP3P RP1P RP9P Degree rise Electric Appliance Sizing Chart...
1" Computerized temperature control — ensures temperature stability Floor (C) 12" Model GWH 715 ES N for natural gas (NG) supply Model GWH 715 ES L for liquid propane (LP) supply 15-year warranty Qualifi es for $300 tax credit GWH 715 ES Technical Specifi cations...
Applications manual 2.3 Bosch GWH C 800 ES Features: Electronic ignition and built in power vent GWH C 800 ES Installation Clearances Condensing technology with 92% thermal effi ciency Top (A) 12" Vents vertically or horizontally with 3" or 4" PVC, CPVC or ABS Front (B) 1"...
Applications manual 2.4 Outdoor Installation for GWH 715 ES, Installation on wood siding and GWH C 800 ES Outdoor Kit (PTOK) installation: The installation of this outdoor kit (PTOK) is required when installing either of the above appliances outdoors Outdoor cap easily retrofi ts to these indoor models...
Applications manual 2.6 Bosch GWH 345 ESR Features: Specifi cally designed for recirculating applications Electronic ignition and built in power vent GWH 345 ESR thermal effi ciency of 82% Vents vertically or horizontally with 3" stainless steel (AL29-4C) Direct vent room-sealed combustion Computerized temperature control —...
1 0 | Applications manual 2.6 Bosch GWH 450 ESR Features: Specifi cally designed for recirculating applications Electronic ignition and built in power vent GWH 450 ESR thermal effi ciency of 81% Vents vertically or horizontally with 3" stainless steel (AL29-4C) Direct vent room-sealed combustion Computerized temperature control —...
Applications manual | 11 2.7 Bosch GWH 425 EF Features: Electronic ignition and built in power vent Thermal effi ciency of 82% Vents with 4" stainless steel or galvanized vent pipe Specifically designed for horizontal vent terminations Modulating gas valve — ensures temperature...
1 2 | Applications manual 2.8 Bosch GWH 425 HN GWH 425 HN Installation Clearances Features: Top (A) 12" Hydro-generated ignition Front (B) 4" 80% thermal effi ciency Endless hot water for one major application at a time Back 0"...
Applications manual | 13 2.9 Bosch GWH 425 PN GWH 425 PN Installation Clearances Features: Top (A) 12" Standing pilot ignition Front (B) 4" 78% thermal effi ciency Endless hot water for one major application at a time Back 0"...
Applications manual 3 Domestic Water Heating Applications Potable water Potable water is water that is suitable for drinking. Bosch Water Heating appliances are approved to heat potable water only. Heating any other liquid other than potable water will void the manufactures warranty covering the appliance.
Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # POU1 rev 06/06 Bosch Water Heating Applications manual | 11.2007...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # POU2 rev 06/07 Application manual | 11.2007 Bosch Water Heating...
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Applications manual | 21 3.1.3 Bosch GWH-260PN gas tankless water heater The Bosch GWH-260PN gas tankless water heater offers a compact and lightweight design for easy installation. This unit is equipped with standing pilot ignition and is intended for low volume applications.
Whole house applications cover the typical home applications up to a 2 or 3 bedroom house. See the sizing guide (Section 2.1) to determine the best Bosch water heater model for your application. An enhanced design including an Ariston mini tank in line to the hot water source will reduce the wait time for hot water and improve temperature stability.
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # WH1R rev 06/07 Bosch Water Heating Applications manual | 11.2007...
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Applications manual 3.2.3 Bosch ProTankless gas water heater Below are two examples of Bosch ProTankless gas water heater installations for the whole house. One example shows an Ariston mini tank in line for reduced hot water wait time and increased temperature stability.
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Applications manual | 25 3.2.4 Bosch ProTankless gas water heater with domestic recirculation loop The circulator should be controlled by an external aquastat, or with a timer to run only during times of expected hot water usage. Cold Bosch GWH 715 ES,...
4 High Volume Potable Water Heating Potable water Potable water is water that is suitable for drinking. Bosch Water Heating appliances are approved to heat potable water only. Heating any other liquid other than potable water will void the manfuctures warranty covering the appliance.
4.1.1 Bosch ProTankless gas water heater in parallel for commercial applications Two Bosch ProTankless units will have double the activation rate of a single unit. When sizing gas line, ensure the gas line is sized to carry the BTU load of two units plus any additional gas appliances. See the installation manuals for a gas line sizing chart.
4.2 Cascading unit applications A cascading application should be considered if the potential hot water demand exceeds the capacity of one GWH 715 ES or GWH C 800 ES. The cascading set up supports variable fl ow inputs and is designed for large homes and commercial applications.
0 feet of head 0 GPM 1 GPM 2 GPM 3 GPM 4 GPM 5 GPM 6 GPM water flow rate Pressure drop curves Note : Flow above 6 GPM is not permitted. Bosch Water Heating Applications manual | 11.2007...
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3 0 | Applications manual 4.3.2 Single unit tank loading application plumbing diagram The GWH 345/450 ESR is specifi cally designed for this application. Cold water feed Bosch GWH 345 ESR, Bosch GWH 450 ESR Symbols Potable water External Pressure...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # ESTL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
Some jurisdictions may not allow these types of applications. 5.1.1 Radiant space heating and DHW plumbing diagram Bosch GWH 345 ESR, Bosch GWH 450 ESR Cold water feed...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # EROL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
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3 4 | Applications manual 5.1.2 Fan coil space heating and DHW plumbing diagram Bosch GWH 345 ESR, Bosch GWH 450 ESR Cold water Fan Coil feed Symbols Potable water Flow Storage expansion tank check tank Fan Coil valve Pressure...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # EFCOL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
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3 6 | Applications manual 5.1.3 Baseboard/ Radiant Panel space heating and DHW plumbing diagram Bosch GWH 345 ESR, Bosch GWH 450 ESR Cold water feed Symbols Potable water Flow Flow Storage Baseboard/ expansion tank check direction tank Radiant valve...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # EBBOL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
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3 8 | Applications manual 5.1.4 Baseboard/ Radiant Panel space heating and DHW (with Ariston mini tank) plumbing diagram Bosch GWH 345 ESR, Bosch GWH 450 ESR Cold water feed Aquastat well with 12k ohm thermistor (insulate piping around thermistor)
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # EBBAOL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # BBNTOL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
Applications manual 5.2 Indirect Tank Applications 5.2.1 Indirect Baseboard/ Radiant Panel space heating and DHW plumbing diagram Note: Not suitable for space heating applications requiring high water temperature. Bosch GWH 345 ESR, Bosch GWH 450 ESR Cold water feed Cold...
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Additional safety and/or auxiliary equipment may be needed. This diagram is for reference use by officials, designers and licensed installers. It is expected that installers have adequate knowledge of accepted industry practices for the equipment, procedures, and applications involved. Drawing is not to scale. Drawing # EID BBOL revA 10/07 Bosch Water Heating Applications manual | 11.2007...
6 Maintenance Drawings Bosch appliances are designed to last for many years. In order to keep the heater operating properly, periodic maintenance is required. Please consult the installation manual for maintenance intervals. A descaling procedure drawing is included to assist in clearing the water heater of mineral deposits that may build up over time.
Applications manual | 45 6.1 Descaling procedure diagram Bosch GWH 715 ES, Bosch GWH C 800 ES, Bosch GWH 425 HN or Bosch GWH 425 PN Symbols Circulating pump Flow direction Filter Service valves Note: This drawing is conceptual in nature and does not purport to address all design, installation or safety considerations.