IN-SERVICE TESTING
The purpose of in-service testing is to regularly monitor the thermal performance of the
thermostatic mixing valve. Deterioration in performance can indicate the need for
service work to be carried out on the system.
If the authority concerned does not have a planned test and maintenance schedule then
the suggestions below should form the basis of a new system.
At intervals of 6 - 8 weeks and 12 - 15 weeks after commissioning:-
1. Check supply parameters are still within the expected values if not check system for
faults.
2. Carry out commissioning procedures a to c using the same test equipment, if the
mixed water temperature has changed a significant amount (by more than 1K)
check to ensure in line filters are clean, that the check valves are working and all
isolating valves are fully open. If no fault can be found check and record the mixed
water temperatures and readjust mixed water temperature to the values in table 2.
Complete the commissioning procedure a to f if the mixed water temperature
exceeds the values of the maximum recorded temperature by more than
2K the need for service work is indicated.
Depending on the results of these two tests the following should be adopted
a) If a small change (e.g. 1K to 2K) occurs in one of these tests or there is no
significant change (e.g. 1K maximum) then the next in service test should be 24 to
28 weeks after commissioning.
b) If small changes occur in both tests or a larger change occurs in one test
(exceeding 2K) then the next in service test should be carried out 18 to 21 weeks
after commissioning.
These results can then be used to set a service interval which tests have shown can be
used with no more than a small change in mixed water temperature. This method of
determining service intervals is used to take into account various in-service conditions
(i.e. water condition) that the valve may experience.
Installation, operating and maintenance
instructions for Gummers
H64WMT & H64DMT
Sequential Integral Thermostatic Bib Tap
Before installing or operating this tap please read this manual carefully and retain it for future
reference.
Bristan operate rigorous quality control procedures but in the unlikely event of finding this pack
incomplete, or needing further technical information please contact the manufacturer.
TMV3 Approval Certificate number BC351/0508
LP - WE LOW PRESSURE ECONOMY WASH BASIN
HP W HIGH PRESSURE WASH BASIN
WRAS Approval Certificate number 0804010
Birch Coppice Buisness Park
Dordon
Tamworth
Staffordshire
B78 1SG
Tel: 0844 7016274
Free fax Order Line: 0808 1611002
Email: customercare@bristan.com
Website: www.bristan.com/trade
BristanGroup Limited
800386H
Customer Care
0844 7016273
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