BS 7942:2011

Foreword
0 Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 TMV materials
5 Classifications
6 Backflow prevention devices
7 Removable devices (RDs)
8 Specimens and test sequences
9 Leaktightness
10 Durability
11 Performance
12 Designation
13 Marking
14 Installation and operating instructions
Annexes
Annex A (normative) - Apparatus and measurements for
        durability test on thermostat
Annex B (normative) - Test for the durability of on/off
        flow control
Annex C (normative) - Test for the durability of manual
        diverters
Annex D (normative) - Test for the durability of
        diverters having an automatic return
Annex E (normative) - Test for the durability of
        thermostat
Annex F (normative) - Apparatus for performance tests
Annex G (normative) - Determination of thermometer
        response time
Annex H (normative) - Test for flow rate and sensitivity
        of temperature control
Annex I (normative) - Tests for TMVs having electronic
        temperature adjustment
Annex J (normative) - Test for mixed-water temperature
        overshoot on operation of diverter
        (manual or automatic return)
Annex K (normative) - Test for mixed-water temperature
        overshoot on operation of second outlet
Annex L (normative) - Test for mixed-water temperature
        overshoot starting from ambient temperature
Annex M (normative) - Test for mixed-water temperature
        overshoot on adjustment of mixed-water
        temperature
Annex N (informative) - Assessment of transient values
Annex O (normative) - Test for thermal shut-off
Annex P (normative) - Test for temperature stability
        with changing water supply pressure
Annex Q (normative) - Test for temperature stability
        with changing water supply temperature
Annex R (normative) - Test for temperature stability
        at reduced flow rate
Annex S (normative) - Additional testing after failure
        to meet performance and durability
        requirements
Annex T (informative) - Summary of thermal
        performance requirements
Annex U (informative) - Recommendations on
        commissioning and in-service tests
Annex V (informative) - Frequency of in-service tests
Bibliography

Describes performance and material requirements and gives test methods for three types of TMV, of nominal size up to and including DN25, for use in care establishments. The TMVs covered by the standard are those which are suitable for the hot and cold water supply pressures and temperatures.

This British Standard specifies performance and material requirements and gives test methods for three types of TMV, of nominal size up to and including DN25, for use in care establishments. The TMVs covered by this standard are those which are suitable for the hot and cold water supply pressures and temperatures given in Table 1, and those which are suitable for the applications given in Table 2. Annex A to Annex E give the apparatus and test methods for the durability of TMVs, Annex F to Annex M and Annex O to Annex S give the apparatus and test methods for the performance of TMVs. Annex N gives an assessment of transient values, Annex T gives a summary of thermal performance requirements and Annex U and Annex V give recommendations for commissioning and in-service tests. Table1 TMV general use conditions Pressure/temperature range High pressure (HP) Low pressure (LP) Operating pressure  Maximum static water pressure (MPa) 1.0 1.0  Flow pressure, hot and cold (MPa) 0.1 to 0.5 0.02 to 0.1 Operating temperature  Hot supply temperature (°C) 55 to 65 55 to 65  Cold supply temperature (°C) 5 to 20 5 to 20 Table2 Mixed-water temperature Application Designation A) Mixed-water temperature (at point of discharge)°C max. Bidet HP-B, BE; LP-B, BE 38 Shower HP-S, SE; LP-S, SE 41 Washbasin HP-W, WE; LP-W, WE 41 Bath (44°C fill) HP-T44; LP-T44 44 Bath (46°C fill) HP-T46; LP-T46 46 Bath and shower mixer (44°C bath fill) HP-D44; LP-D44 41 (shower); 44 (bath) Bath and shower mixer (46°C bath fill) HP-D46; LP-D46 41 (shower); 46 (bath) NOTE For washbasins, washing is assumed to take place under running water. A) A TMV with a diverter designation (D) has the capability to change and control the mixed-water outlet temperature in line with the temperatures defined above when the supply path is changed from bath to shower or shower to bath.