Advertenties
Beschikbare talen
Beschikbare talen
GB
ENGLISH
8 - PARTICULAR INSTALLATIONS
8.1 - Inhibiting self-priming
The product is made and supplied with the capacity of being self-priming. With reference to
par. 4, the system is able to prime and therefore operate in whatever installation configura-
tion chosen: below head or above head. However there are cases in which the self-priming
capacity is not necessary, or areas where it is forbidden to use self-priming pumps. During
priming the pump obliges part of the water already under pressure to return to the suction
part until a pressure value is reached at delivery whereby the system can be considered
primed. At this point the recirculating channel closes automatically. This phase is repeated
each time the pump is switched on, even already primed, until the same pressure value that
closes the recirculating channel is reached (about 1 bar).
When the water arrives at the system intake already under pressure (maximum allowed
2 bar) or when the installation is always below head, it is possible (and mandatory where
local regulations require it) to force the closure of the recirculating pipe, losing the self-
priming capacity. This obtains the advantage of eliminating the clicking noise of the pipe
shutter each time the system is switched on.
To force closure of the self-priming pipe, proceed as follows:
1. Disconnect the power supply;
2. empty the system (unless you decide to inhibit self-priming at the first installation);
3. remove the drainage cap on Face E, taking care not to drop the
(Fig.18);
4. with the aid of pliers take the shutter out of its seat. The shutter will be extracted
together with the O-Ring and the metal spring with which it is assembled;
5. remove the spring from the shutter; insert the shutter in its seat again with the re-
spective O-Ring (side with gasket towards the inside of the pump, stem with cross-
shaped fins towards the outside);
6. screw on the cap after having positioned the metal spring in side so that it is com-
pressed between the cap itself and the with cross-shaped fins of the shutter stem.
When repositioning the cap ensure that the respective O-Ring is always correctly
in its seat;
7. fill the pump, connect the power supply, start the system.
63
O-Ring
Figure 18
Advertenties
