Single Pipe Suction Lift With De-Aerator; Pipework; Appliance Oil Isolation Valve; Water Systems And Pipework - Bosch Worcester Greenstar Utility 32/50 Installation, Commissioning And Servicing Instruction Manual

4.3.3

Single pipe suction lift with de-aerator:

Maximum suction height 3.5 metres. The oil tank [1] must be positioned
below the oil pump [9]. Create an inlet and return loop between the de-
aerator [12] and oil pump [9].
A non-return valve must be incorporated within the de-aerator or fitted
to the oil line between the oil storage tank [1] and the de-aerator [12].
A top feed oil tank fitted with a de-aerator using an internal non-return
valve should have any non-return valves fitted in the base of the tank to
the suction line removed to assist purging air from the oil line.
1
2 3 4
Fig. 5 De-aerator feed
Maximum pipe run for single pipe suction lift with de-aerator
FUEL FLOW RATE 2.5kg/h
Head (m) 8mmØ
0 100
0.5 95
1.0 80
1.5 70
2.0 60
2.5 45
3.0 35
3.5 25
Table 4
Table 4 & figure 5 are guides only and do not in any way
override the de-aerator manufacturer's instructions.
4.3.4

Pipework

▶ Refer to the oil supply sections Single pipe gravity feed
system: 4.3.1, Double pipe sub-gravity feed system: 4.3.2 & Single
pipe suction lift with de-aerator: 4.3.3 for oil supply pipework
configurations.
Oil supply pipework considerations:
• Lay the oil supply pipe as straight and level as possible to avoid air
pockets and unnecessary friction losses.
– Route away from the appliance access door or other hot surfaces.
• Install a manual isolating valve to the oil supply pipe, as close to the
oil storage tank as possible.
• Fit an oil strainer and water separator to the oil supply pipe, near the
oil storage tank.
– Fit an additional oil filter (70 μm max filtration size) close to the
appliance, but not inside the appliance casing.
• Fit a fire valve in accordance with BS 5410.
– The fire valve should be fitted externally to the building with the
fire valve sensor located within the appliance case.
– A fire valve with a shut off temperature of 85°C or higher must be
fitted to avoid the possibility of nuisance shut offs.
– A capillary type valve provides a neat and simple installation.
Alternatively, a fusible link or electrical system may be used.
• Under no circumstances should a combination isolating/fire valve be
used as the sole fire protection device.
Greenstar Utility ErP - 6 720 821 751 (2018/04)
12 6 8
9 10
5
3 7 13
5kg/h 10kg/h 10kg/h
8mmØ 8mmØ 10mmØ
55 26 100
45 23 100
40 20 90
35 17 75
30 14 65
25 11 50
15 8 35
10 5 20
4.3.5

Appliance oil isolation valve

▶ Use copper pipe of the correct diameter according to the information
shown in oil supply sections 4.3.1, 4.3.2 & 4.3.3.
– If using soft copper pipe (R220) with a compression fitting, an
insert must be used to prevent the pipe from collapsing or
distorting when the fitting is tightened.
▶ Slide nut [1] and olive [5] onto the oil supply pipe [4].
▶ Slide insert [3] into the pipe.
▶ Offer the pipe to the fitting [2] and tighten the nut [1].
1
5
4
3
Fig. 6 Isolation valve bracket removed for clarity
▶ Use flexible hoses to connect from the appliance oil isolation valve to
the oil pump.
4.4

Water systems and pipework

NOTICE:
▶ The appliance should not be allowed to operate with
a return temperature of less than 30°C when the
system is up to operating temperature.
Primary system plastic pipework:
• Any plastic pipework used for the CH system must have a polymeric
barrier, complying with BS 7921 and installed to BS 5955 with
1000mm (minimum) length of copper or steel pipe connected to the
appliance.
• Plastic pipework used for underfloor heating must be correctly
controlled with a thermostatic blending valve limiting the
temperature of the circuits to approximately 50°C with 1000mm
(minimum) length of copper or steel pipe connected to the
appliance, and a 20K differential must be maintained at the
appliance.
Primary system/connections/valves:
• Do not use galvanised pipes or radiators.
• All system connections, taps and mixing valves must be capable of
sustaining a pressure of 3 bar.
• Radiator valves should conform to BS 2767:10.
• All other valves should conform to BS 1010.
• An automatic bypass valve must be connected between the heating
flow and return where TRVs are used on all radiators, fitted to give at
least a 3 metre circuit when activated.
• Drain cocks are required at all the lowest points on the system.
• Air vents are required at all high points on the system.
Pre-Installation
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