What is BS EN 12309-7 - Provisions for hybrid gas-fired sorption appliances about?
BS EN 12309 is a European Standard that discusses the gas-fired sorption appliances for heating and/or cooling. The BS EN 12309 series aims to provide with best industry practices that ensure gas-fired sorption appliances for heating and/or cooling are safe and reliable for use.
Appliances covered by BS EN 12309 include one or a combination of the following:
- Gas-fired sorption chiller
- Gas-fired sorption chiller/heater
- Gas-fired sorption heat pump
BS EN 12309 applies to appliances designed to be used for space heating or cooling or refrigeration with or without heat recovery.
BS EN 12309 applies to appliances having flue gas systems of type B and C (according to CEN/TR 1749) and to appliances designed for outdoor installations.
BS EN 12309 only applies to appliances having:
- Integral burners under the control of fully automatic burner control systems
- Closed system refrigerant circuits in which the refrigerant does not come into direct contact with the water or air to be cooled or heated
- Mechanical means to assist transportation of the combustion air and/or the flue gas
The above appliances can have one or more primary or secondary functions (i.e., heat recovery - see definitions in EN 12309-1:2014). In the case of packaged units (consisting of several parts), BS EN 12309 applies only to those designed and supplied as a complete package.
BS EN 12309-7 is the seventh part of the series that deals particularly with the specific provisions of hybrid heating appliances based on gas-driven sorption heat pumps as defined in Part 1.
The heating appliances covered by BS EN 12309-7 are of a hybrid type, an encased assembly or assemblies combining a direct or indirect-fired sorption heat pump for base load and a peak load condensing boiler with only one flue system, electrical supply cable and human machine interface to the end user. The direct- or indirect-fired sorption heat pump integrated in the hybrid appliances in BS EN 12309-7 could be intermittent or continuously operating ab or adsorption heat pump.
Note 1: The appliances having their condenser cooled by air and by the evaporation of external additional water are not covered by BS EN 12309.
Note 2: Installations used for heating and/or cooling of industrial processes are not within the scope of BS EN 12309.
Who is BS EN 12309-7 - Provisions for hybrid gas-fired sorption appliances for?
BS EN 12309-7 on specific provision for hybrid appliances for gas-fired sorption is relevant to:
- Gas-powered device manufacturers
- Heat pump manufacturers
- Ventilation and air-conditioning system manufacturers
- Quality control and testing personnel
Why should you use BS EN 12309-7- Provisions for hybrid gas-fired sorption appliances?
The types of hybrid heating appliances considered in BS EN 12309-7 are variable capacity delivering a variable heating fluid outlet temperature dependent on the outdoor (ambient air) and the design indoor (room) temperatures as well as the selected heat sink conditions.
BS EN 12309-7 presents the design temperatures for heating (the dry bulb outdoor coldest temperature) for each reference heating season, the design indoor (room) temperature (TR) as well as the balance point or heating limit temperature (TBP) for three heating seasons (climatic conditions); namely colder (C), average (A) and warmer (W). As a result, you can estimate the seasonal performance of such hybrid appliances with the reference and pivot part load ratios provided.
Adopting BS EN 12309-7-compliant best industry guidance, can thus help manufacturers demonstrate the quality, reliability and performance of hybrid gas-fired sorption appliances to determine whether they are fit for purpose.