Unigas G335A Installation Manual page 25

About the use of fuel pumps
Do not use fuel with additives to avoid the possible formation over time of compounds which may deposit between the gear teeth,

thus obstructing them.
After filling the tank, wait before starting the burner. This will give any suspended impurities time to deposit on the bottom of the
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tank, thus avoiding the possibility that they might be sucked into the pump.
On initial commissioning a "dry" operation is foreseen for a considerable length of time (for example, when there is a long suction
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line to bleed). To avoid damages inject some lubrication oil into the vacuum inlet.
Care must be taken when installing the pump not to force the pump shaft along its axis or laterally to avoid excessive wear on the

joint, noise and overloading the gears.
Pipes should not contain air pockets. Rapid attachment joint should therefore be avoided and threaded or mechanical seal jun-

ctions preferred. Junction threads, elbow joints and couplings should be sealed with removable sg component. The number of jun-
ctions should be kept to a minimum as they are a possible source of leakage.
Do not use PTFE tape on the suction and return line pipes to avoid the possibility that particles enter circulation. These could depo-
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sit on the pump filter or the nozzle, reducing efficiency. Always use O-Rings or mechanical seal (copper or aluminium gaskets) jun-
ctions if possible.
An external filter should always be installed in the suction line upstream the fuel unit.
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ATTENTION: before the burner first start, it is mandatory to fill the adduction pipes with diesel fuel and bleed out residual
air bubbles. Prior to switching on the burner, check direction of rotation of the pump motor by briefly pressing the starter
switch; ensure there are no anomalous sounds during equipment operation, and only then turn on the burner. Neglect to
comply with this requirement will invalidate the burner warranty.
HP-Technick UHE-A..
Oil viscosity
Oil temperature
Min. suction pressure
Max. suction pressure
Max. return pressure
Rotation speed
1. Connection for manometer 1 – delivery (M1) – G1/4
2. Connection for manometer 2 – suction (M2) – G1/4
3. Connection for manometer 3 (M3)
A. Suction connection– G1/2
D. Direct - clockwise
I. Indirect – counter clockwise
R. By-pass connection– G1/2
S. Delivery connection – G1/2
VR. After removal of cover screw: pressure regulation
Suntec T..
Viscosity
Oil temperature
Minimum suction pressure
Maximum suction pressure
Rated speed
Key
1 Inlet G3/4
2 Pressure gauge port G1/4
3 Vacuum gauge port to measure the inlet vacuum G1/4
4 To pressure adjusting valve G3/4
"Note: pump with "C" rotation.
3 ÷ 75 cSt
0 ÷ 150°C
- 0.45 bar to avoid gasing
5 bar
5 bar
3600 rpm max.
A
3 - 75 cSt
0 - 150 °C
- 0.45bar to prevent gasing
5 bar
3600 rpm max.
25
2
VR
I
PART II: INSTALLATION
2
R
3
S
VR
1
D
A