11
THERMOSTATIC MIXING VALVES: D1088 & D1089
INSTALLATION, OPERATING AND MAINTENANCE INSTRUCTIONS
MAINTENANCE - TMV2 & TMV3
Most domestic water supplies contain calcium which will separate out when the water is
heated in a system. The degree and speed of scaling may vary depending on factors such
as water flow rates, system design, the hardness of the water and the temperature to which
the water is heated.
Deposits of scale may over time form in the valve, particularly at the hot inlet. The formation of
the scale may adversely affect the performance of the valve which will be detected during the
in-service testing. If this occurs it will be necessary to remove the valve for de-scaling
and service.
If required, the internal working parts can be removed and cleaned as follows:
1.
Isolate hot and cold water supply.
2.
Remove the valve to a clean working area.
3.
Remove the protective cap.
4.
Unscrew the headwork of the valve.
5.
Carefully remove the temperature-sensitive and piston assembly, put to one side.
6.
Remove the main spring and flow guide, carefully put to one side.
7.
Inspect the components for contamination or damage.
8.
Clean or replace as necessary.
9.
Remove the O-ring.
10.
Clean the valve body and Headwork using a propriety de-scaler (approved for use on
potable water applications).
11.
Thoroughly rinse the body and headwork in clean potable water.
12.
Carefully fit new O-ring to body.
13.
Carefully re-fit all components and perform the commissioning sequence.
If after cleaning the valve and replacing the O-ring seals the valve does not function correctly,
it may be necessary to replace the thermal element.
Figure 5 - D1088 pictured, exploded views
Fixing Screw
Protective Cap
Headwork
Thermal element
and piston assembly
Flow guide
Main spring
O-ring
Sealing Gaskets
Union Nut
Tailpiece Assembly
Check Valve
Tailpiece
Wafer Strainer
Olives
Compression Nut
