Routine Inspection & Maintenance Operations - Apartment Heating System - Heatrae Sadia HI-MAX INSTANT ID 5-60 Installation, Operation And Maintenance Manual

9.4 Routine inspection & maintenance
operations - apartment heating system
9.4.1 Check Safety Valve
The safety valve should be checked periodically to
ensure that the valve is operational. This is done by
simply twisting the red plastic cap at the top of the
valve. In so doing, a small burst of water will discharge
from the valve, which can be witnessed through the
tundish. After doing so check the system pressure and
top back up to 1.30 bar g as necessary.
WARNING
Although the amount of water discharged
from the safety valve is not likely to be great.
It is important to note that it is likely to be hot
and carries a risk of scalding.
Figure 58: Operating the safety valve
9.4.2 Check expansion vessel gas charge
1) Isolate the central heating fl ow and return
connections.
2) Drain down the Heatrae Sadia HI-MAX INSTANT unit
on the apartments' heating circuit using the drain valve
on the bottom right hand side of the unit.
See Figure 59 below.
3) Using a pressure gauge, check the gas charge in the
expansion vessel. This should be 1.0 bar g.
4) If the gas charge is too low, recharge the gas pressure
using a bicycle pump or compressor.
Figure 59: Apartment heating drain valve
9.4.3 Check inhibitor
1) Open the central heating drain cock to take a
small sample of the water from the apartment central
heating system. Then using a protector test kit, check
the concentration of inhibitor in the system.
2) Top up the system using the fi lling loop and add
inhibitor as necessary.
Follow the procedure in section 8.1.6.
9.4.4 Check pressure gauge
1) With the apartment central heating system cold,
check the system pressure. This should be 1.3 bar g.
Top up using the fi lling loop as necessary.
9.4.5 Check sensors are in their pockets
1) Check the heating fl ow and return sensors are in
their appropriate pockets. The heating fl ow sensor can
be identifi ed by a red tag and the return by a blue tag.
Now fi ll in the Benchmark service record on page 55
of this manual.
CAUTION
It is important that any work carried out on this
unit is done by a competent engineer who is
familiar with and understands the design of
the system. This HIU is linked to a network
and as such any unauthorised modifi cations
or adjustments to the way the unit is set up to
run could inadvertently affect the operation of
other parts of the system. Authorisation from
the community heating supplier should be
sought before any system changes are carried
out.
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