BS EN 12977-2:2018 pdf download

BS EN 12977-2:2018 pdf download.Thermal solar systems and components Custom built systems
1 Scope
This European Standard applies to small and large custom built solar heating systems with liquid heat transfer medium for residential buildings and similar applications, and gives test methods for verification of the requirements specified in EN 12977-1:2018.
This document also includes a method for thermal performance characterization and system performance prediction of small custom built systems by means of component testing and system simulation.
Furthermore, this document contains methods for thermal performance characterization and system performance prediction of large custom built systems.
This document applies to the following types of small custom built solar heating systems:
一systems for domestic hot water preparation only;
一systems for space heating only;
一systems for domestic hot water preparation and space heating;
一others (e.g. including cooling).
This document applies to large custom built solar heating systems, primarily to solar preheat systems,with one or more storage vessels, heat exchangers, piping and automatic controls and with collector array(s) with forced circulation of fluid in the collector loop.
This document does not apply to
一systems with a store medium other than water (e.g. phase- change materials),
一thermosiphon systems,
一integral collector-storage (ICS) systems.
6.2.4 High-temperature protection
6.2.4.1 Scald protection
If the temperature of the domestic hot water in the system can exceed 60 °C, check the design plan or the system documentation to see whether the system is provided with an automatic cold water mixing device or any other device to limit the maximum tapping temperature to 60°C.
6.2.4.2 High-temperature protection ofmaterials
Ensure by checking the hydraulic scheme and/or by calculation and taking into account the most adverse conditions for the materials of all parts of the system, that the maximum temperatures which may occur do not exceed the maximum permissible temperatures for the respective materials, taking into account also pressure conditions and/or mechanical stress if relevant. NOTE Both transients (high temperature peaks of short duration) and stagnation of longer duration may create adverse conditions for the respective material.
6.5 Safety equipment and indicators
6.5.1 Safety valves
Check the design plan and the system documentation to verify that each collector or each section of collector array which can be shut off is fitted with at least one suitable safety valve. Check the specification of the safety valves, whether the materials fulfil the requirements given in EN 12977-1:2018, 6.5.1. Check whether the size of the safety valve is correct, in compliance with the requirements given in EN 12977-1:2018, 6.5.1. Additionally, for large custom built systems: For testing the system behaviour after release of one or more safety valves according to the requirements given in EN 12977-1:2018, 6.5.1, check the electric and hydraulic schemes or any other part of the documentation according to EN 12977-1:2018, 6.8.3.