Hot water discharge from tundish
This indicates a malfunction of a thermal cut-out, operating thermostat or the combined temperature
and pressure relief valve. Turn off the electrical supply to the immersion heater and also isolate an
indirect unit from the boiler. Contact the installer or competent engineer.
Cold water inlet control (Multibloc) See Page 2 Items 3 - 4
This combination consists of a pressure reducing valve with integral strainer, check valve and
expansion valve with stainless steel seat. The pressure settings are set and locked in the factory and
are shown on the top of each valve. For optimum performance the following installation instructions
should be complied with.
Installation
1.
Cold water supply to be 22mm nominal size.
2.
Flush supply pipework before connection to remove all flux and debris prior to fitting the inlet
controls. Failure to do this may result in irreparable damage to the controls and will invalidate
the warranty.
3.
The “MULTIBLOC” can be fitted in any orientation to suit the installations as long as it is fitted
in the correct flow direction. Check the flow arrows on the side of the body.
4.
The expansion valve should be either horizontal or upright - if fitted inverted, debris may be
deposited on the seat and cause fouling of the seat when the valve operates. Check direction
of flow arrows.
5.
The black plastic plugs in the body are pressure gauge connections to enable pressure
monitoring to be carried out, should the system develop a fault. It is recommended that these
be accessible (the pressure reducing valve has two - only one need be accessible).
6.
Expansion relief drain pipework must be connected to a safe visible discharge point via a
tundish and the pipework must have a continuous fall.
7.
The pressure reducing valve has two outlets, the second one is for a balanced cold water
supply, to a shower or a bidet
(over rim type only, ascending spray type requires type AA,
AB or AD air gap)
(Major shower manufacturers advise fitting a mini expansion vessel in
the balanced cold supply pipework to accommodate thermal expansion and prevent
tightening of shower controls). Using the balanced cold connection to feed outlets that
do not require a balanced cold supply can reduce the flow available to the unvented
cylinder.
The balanced cold supply is blanked off.
8.
If an expansion vessel is to be fitted it must be connected to the cold feed pipe between the
pressure reduction valve, (Multibloc) (3) and the cylinder.
NOTE: If the unit has been commissioned and is to be unused for more than 8 weeks it is
advisable to turn off the cold supply and draw off approximately 5 litres of water through a hot
tap. NB The cold supply must be opened prior to use.
The Benchmark Log Book enclosed with the cylinder must be completed after
commissioning the system and handed to the customer for future reference.
INSTALLATION AND SERVICING INSTRUCTIONS
-5-
