BS 4856-3:1975

Co-operating organizations
Foreword
Methods
1 Scope
2 References
3 Definitions
4 Operating conditions of units
5 Nomenclature
6 Object of the test method
7 Testing conditions
8 Instrumentation
9 Test equipment
10 Test facility
11 Air temperature measurement
12 Test method
13 Test method (air side measurements)
14 Calculations
15 Rating tests
16 Example
17 Sensible and latent cooling rating tests
18 Enclosure sweating tests and condensate disposal
       tests
Appendix
A Heating units with fan installed downstream of
       the coil
Tables
1 Steady state conditions
2 Rating test for steam as primary fluid
3 Rating tests for water or heat transfer fluid
4 Latent cooling rating test series
5 Enclosure sweat test conditions
Figures
1(a) Thermometer pocket for steam test
1(b) Thermometer pocket for hot water test
1(c) Thermometer pocket for use in vertical pipes
       over 75 mm diameter
1(d) Thermometer pocket for use in horizontal pipes
       over 75 mm diameter
2 Multi-junction differential thermocouple
3(a) Inverted U-tube manometer
3(b) Piezometer ring
4(a) Thermometer shield
4(b) Thermocouple shield
5 Inlet air sampling tube
6 Outlet air sampling tube
7 Steam test equipment
8 Water test equipment
9 Hot water test equipment (maximum water
       temperature above 95 deg C)
10(a) Arrangement A of test apparatus
10(b) Arrangement B of test apparatus
11 Temperature and total pressure probe
12 Air flow mixers
13 Inlet temperature measurement
14 Traverse stations
15 Definition of x
16 Pressure-flow characteristics
17 Heat transfer
18 Thermal efficiency
19 Water temperature correction factor heating
20 Water temperature correction factor cooling
21 Graph of Qn versus qar at (tfi - tai) = 60 deg C
22 Graph of Qn versus mf at qar = 0.93 cubic m/s
23(a) Graph of Ra and B versus qar
23(b) Graph of Rwm versus mf

Units for use with additional ducting containing fluid to air heat exchangers and incorporating their own electrically powered fan system. For heating or cooling applications, the latter with or without dehumidification under frost-free conditions.

This Part of this British Standard deals with methods of carrying out thermal and volumetric tests on units intended for use with additional ducting containing fluid to air heat exchangers and incorporating their own electrically powered fan system. The units may be either for heating or for cooling applications and the latter may be with or without dehumidification under frost-free conditions. The tests are to be carried out on units in an essentially clean condition.