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Applications manual

 

 

5 Open Loop Space Heating

Introduction

This section is designed to provide a road map of techniques for using a tankless water heater to heat domestic water and at the same time provide space heating in residential applications. As with all installations, check with the local authority having jurisdiction. Some jurisdictions may not allow these types of applications.

5.1 External storage tank

The appliances shown in this section are approved under ANSI Z21.10.3 and CSA 4.3 as circulating gas water heaters. Only open loop applications are approved under this standard.

5.1.1 Radiant space heating and DHW plumbing diagram

P2

P1

Cold water

DHW

feed

 

Bosch GWH 345 ESR,

Bosch GWH 450 ESR

PS

Symbols

Potable water

Pressure

Flow

Radiant

Storage

piping

tank

expansion tank

relief

direction

 

 

 

valve

 

 

 

Bronze circulator

Thermostatic

Service

12K ohm

 

sized according to

thermistor

 

mixing

valves

 

UPC standards

with immersion

 

valve

 

 

 

 

well

 

 

 

 

 

Note: Piping to fixtures not shown for clarity purposes.

Note: This drawing is conceptual in nature and does not address all design, installation or safety considerations.

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 # ROL

CN revA 10/07

Application manual 11.2007

Bosch Water Heating

Page 32
Image 32
Bosch Appliances GWH 260 PN/HN2 Cold water, Feed, External storage tank, Radiant space heating and DHW plumbing diagram