5-78
5
M
A
INTE
NAN
CE
ARBUS 270
Tabla 11: Suction and boost deficiency (total lack of pressure)
Table 12: Pressure oscillation
Trouble-shooting
Probable causes
Indications and corrections
1. Complete absence of power take-off
revolution.
The machine shall be driven with the power take-off
(PTO) running at 540 rpm.
Visually check whether the pump is being driven.
2. Water missing on reservoir.
A minimum liquid is required for the chemical circuit
operation; otherwise there will be no pressure.
3. Filter valve closed (quick shut-off)
Due to the quick shut-off valve construction charac-
teristic, liquid will flow even in the shut position with
the p ump operating; however, the circulation of liq-
uid will be insufficient.
4. Dirty filter.
The dirty filter will prevent free fluid flow.
Clean the filter at the time of every refill or more frequent
-
ly depending on the water quality and type of chemical.
5. Obstruction in intake hoses.
Check the hose connecting the filter to the pump for
buckling.
Check for obstruction inside the hoses connecting the
reservoir to the filter. Fill the reservoir, open the valve
and check whether there is plenty of water circulating.
6. Air intake.
Check the filter sealing ring.
The filter sealing must be correct, with no leaks.
7. Pump is not suctioning.
Remove the suction valve cover.
Check the repair condition of valves and, if necessary,
replace.
Probable causes
Indications and corrections
1. Slack belts.
Incorrectly taut belts will not drive the pump properly.
2. Entry of air into the intake system.
Caused by a punctured hose, damaged filter sealing
ring, etc.
Check and mend liquid leaks if existing.
3. Pressure regulator.
Check the valve and valve seat to make sure of the
proper adjustment of these components.