UPS 15-50 Selectric and UPS 15-60 Super Selectric circulators are
designed to cater for the majority of domestic wet central heating
systems up to 35kW.
The UPS 15-50 Selectric covers virtually all standard systems whilst
the higher head UPS 15-60 can accommodate larger domestic systems
and higher resistance circuits (eg microbore).
The pumps incorporate a new energy saving three speed motor for
pump to system matching and consequent reduction of hydraulic noise.
The very highest quality pump components provide long life and
maximum resistance to corrosion. Standard port to port dimensions
make these pumps interchangeable when replacing the vast majority
of old pumps.

INSTALLATION

It is preferable to install Grundfos circulators in a vertical pipe
pumping upwards. This position ensures that the pump shaft
is horizontal, which reduces the thrust bearing load and ensures
positive air purging from both the rotor chamber and impeller
housing.
Pumping downwards in a vertical pipe is not recommended as
this may lead to air locking of the pump, with resultant loss of
performance. However, pumping downwards is acceptable
provided an effective air vent is incorporated in the system,
before the pump.

Where pumps can only be installed in horizontal pipework, it is
imperative that the pump shaft is horizontal, or slightly higher
at the vent plug end.
The shaft must not fall below the horizontal plane, even by a
few degrees, as this causes premature wear of the top bearing
and shaft.
Pumps should not be installed with the shaft in a vertical plane,
as this may lead to dry running of the top bearing, noise and
possible pump failure.
To avoid cavitation noise and risk of damage to the bearings the
minimum pump inlet pressure should be 1.4m at 82°C (water
temperature).

APPLICATIONS

The pumps may be used in heating systems containing glycol
based anti-freeze with corrosion inhibitors up to a maximum
of 50% solution but with a 15% performance reduction.
However, if the liquid temperature remains lower than the
ambient temperature during operation, condensation may form in
the stator housing and, may short circuit the motor windings.

FLOW ADJUSTMENT

UPS15-50 -Selectric and UPS15-60 Super Selectric have a three
speed selector switch on the terminal box.