Operation; General - Heatrae Sadia Megaflo Eco SystemFit 145sf Instructions Manual

8. Operation

8.1 General

WARNING
` If water
temperature/pressure relief valve on the
cylinder shut down the heat source. Do
not turn off any water supply. Contact a
competent installer for unvented water
heaters to check the system.
` Do not tamper with any of the safety
valves fitted to the system. If a fault is
suspected contact a competent installer.
` DO NOT bypass the thermal cut-out(s) in
any circumstances.
Benchmark
The cylinder is covered by the Benchmark Scheme
which aims to improve the standards of installation and
commissioning of domestic heating and hot water systems
in the UK and to encourage regular servicing to optimise
safety, efficiency and performance.
Benchmark is managed and promoted by the Heating
and Hotwater Industry Council. For more information visit
www.centralheating.co.uk.
Please ensure that the installer has fully completed the
Benchmark Checklist (page 32) of this manual and that
you have signed it to say that you have received a full and
clear explanation of its operation. The installer is legally
required to complete a commissioning checklist as a means
of complying with the appropriate Building Regulations
(England & Wales).
All installations must be notified to Local Area Building
Control either directly or through a Competent Persons
Scheme. A Building Regulations Compliance Certificate
will then be issued to the customer who should, on receipt,
write the Notification Number on the Benchmark Checklist.
This product should be serviced regularly to optimise its
safety, efficiency and performance. The service engineer
should complete the relevant Service Record on the
Benchmark Checklist after each service.
The Benchmark Checklist may be required in the event of
any warranty work.
Flow performance
When initially opening hot outlets a small surge in flow
may be noticed as pressures stabilise. This is quite normal
with unvented systems. In some areas cloudiness may be
noticed in the hot water. This is due to aeration of the
water, is quite normal and will quickly clear.
Operational faults and their possible causes are detailed
in the Fault Finding section (p.26) of this book. It is
recommended that faults should be checked by a
competent installer.
24
discharges from the
Temperature controls – direct units immersion
heater(s)
`
All immersion heaters are fitted with a thermostat
which is fitted in the centre of the heater plate and a
cut-out which is fitted to the side of the thermostat.
` Access to the thermostat can be made by opening
the immersion heater cover - DISCONNECT THE
ELECTRICAL SUPPLY
COVER(S).
` Temperature adjustment is made by rotating the
adjustment knob on the top of the thermostat. The
adjustment represents a temperature range of 12°C
to 68°C.
` Maximum working temperature is 68°C/154°F. In
very hard water areas limit to 60/65°C (140/150°F).
DO NOT bypass the thermal cut-out(s) in any
circumstances.
Temperature controls - indirect units
The cylinder units are fitted with an indirect thermostat
and thermal cut-out. These controls must be wired in
series with the 2 port motorised zone valves supplied
to interrupt the flow of primary water around the heat
exchanger coil when the control temperature has been
reached.
DO NOT bypass the thermal cut-out(s) in any
circumstances.
The air volume within the product will periodically require
recharging to ensure expanded water is accommodated
within the system. A discharge of water INTERMITTENTLY
from the expansion valve will indicate the air volume has
reduced to a point where it can no longer accommodate
the expansion.
INFO
http://www.baxi.co.uk/information-and-advice/how-to-
videos.htm
To recharge the air volume:-
` Turn off the heat source to the cylinder via
programmers / immersion isolation switch(es).
` Turn off the water supply to the cylinder by turning
off the isolating valve on the 3 bar pressure reducing
valve if fitted at this point or at the 8 bar pressure
relief valve if fitted there. Turn the handle so that
it lies at 90° to the direction of flow. See figure 17
page 28.
` Open the lowest hot tap.
` Hold open the temperature / pressure relief valve
until water ceases to run from the tap and gurgling
noise at the valve stops.
` Close the temperature / pressure relief valve.
`
Turn on the isolating valve at the cold water
combination valve by turning the handle so it lies
parallel to the direction of flow, when water flows
from the hot tap, close tap.
` The air volume will be automatically recharged as
the unit refills. If after following the above actions
water still discharges from the expansion relief valve,
further advice should be sought from a competent
installer or the Megaflo service department.
BEFORE OPENING THE