MAINTENANCE MANUAL
GP/146/99. Issue 9. October 2005
Section 7
LOW PRESSURE MANIFOLD AND FILTER HOUSING
To Remove
Assuming that the HP pump discharge connections have been disconnected
together with gauge, thermal relief and foam connections, it is necessary to remove
the primer discharge pipe from the filter housing to the HP pump body. Remove 10
off M8 bolts to remove the filter body and bypass housing assembly. The low
pressure manifold is connected to the volute body by means of 4 off M10 bolts
surrounding the thermal relief valve and 2 M10 stainless steel socket head cap
screws inside the manifold casing (these 2 screws are fitted with bonded seals to
prevent leakage). The manifold may now be removed. The gasket between the
manifold and the filter housing will require renewal at this stage. The seal between
the volute body and manifold is an O ring.
Towards the rear of the manifold are 2 transfer tubes each sealed by O rings located
within the castings.
The main outlets to the manifold (6 off) are sealed by means of O rings, seated in
grooves in the manifold faces.
Reassembly
When reassembling the manifold, all O rings should be replaced and Loctite 242
should be applied to all threads before refitting.
Filter Housing
The housing contains the main low pressure filter and the primer disengagement
filters, both accessible from the front panel area. These filters, however, must not be
removed whilst the pump is in operation.
The flow across both filters is from outside to inside the cylindrical profiles. The
smaller filter is intended to restrict particle size in water entering the primer
disengaging circuit, whilst the larger filter prevents large particles from entering the
high pressure stage. During pump operation in low pressure mode, and at any time
that the pressure relief valve is open, a flow of water is directed across the large
filter, thus helping to flush the exterior of the filter.
©Hale Products Europe LTD, Warwick
GP/146/99
WTmaint - Issue9. 10-2005October 2005
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