Xylem Bell & Gossett Autocirc e3-4 Series Installation, Operation And Maintenance Manual page 19

• We recommend, that for pump models with pump housing code BT or BS, you install a ball
• A properly installed system should include a method of automatically venting the air that
• Pumps with pump housing code BU (item 20 in Figure 3) incorporate a check valve (item 18 in
• With the shut-off valve closed at the suction side of the pump and with the check valve
• To be able to exclude the complete unit from the system, e.g. for replacement of the pump
The next examples in Figure 5 and Figure 6 show typical installation arrangements for different
return line connection layout, but for single line returns only. For multiple branched supply line
installations, a recirculation line should be installed for each branch.
Figure 5
No.
Installation, Operation and Maintenance Manual
shut-off valve before the pump at least, for future maintenance or repair works.
enters the water supply line during use. Air enters the system each time fresh, cold water is
introduced into the hot water heater. Air may also enter the system any time a plumbing line
is opened, for instance during a faucet/taps change or adding a sprinkler system. We
recommend, that for pump models with pump housing code BT or BS, you install an air vent
mounted in a vertical position.
Figure 3), a ball shut-off valve (item 21 in Figure 3) and a manual air vent valve (item 19 in Figure
3) into the brass pump housing eliminating the need to install these components.
installed at the discharge side, the screw ring (item 5 in Figure 3) can be loosen, thus the
pump motor can be turned in proper position (see section 4.3.3 Rotation of the pump motor
on page 25), or even removed for maintenance (see section 6.4 Disassembly on page 37)
without completely draining the system.
housing without draining the whole system, install additional shut-off valves both at the
suction and at the discharge side of the pump.
Description
1 Tee fitting
2 Hot water return (recirculation) line
3 Hot water supply line
4 Cold water supply line
5 Air vent
6 Check valve
No. Description
7 Circulating pump model BT / BS
8 Ball shut-off valve
9 Hose bib
10 Water heater
11 "Y" fitting
en – Original Instructions
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