English (GB)
9
8. Operate maximum hot and cold flows for at least five minutes
each to ensure air is thoroughly purged from the system.
9. Replace handset on shower hose.
10. Switch on the power supply.
11. Operate the pump in both full hot and cold modes for at least
two minutes each while inspecting for leaks.
Fig. 30 Inspect for leaks after operation
12. Check that all hot-water connections are tight and not leaking,
when the hot water has been run for several minutes.
See fig. 30.
Fig. 31 Re-tighten connections after operation
The first few times the pump is used, the insulating varnish used
on the pump motor may give off an odour. This is perfectly normal
and will diminish with use.
5.1 Shaft seal run-in
The seal faces are lubricated by the pumped liquid, meaning that
there may be a certain amount of leakage from the shaft seal.
When the pump is started up for the first time, or when a new
shaft seal is installed, a certain run-in period is required before
the leakage is reduced to an acceptable level. The time required
for this depends on the operating conditions, i.e. every time the
operating conditions change, a new run-in period will be started.
Under normal conditions, the leaking liquid will evaporate. As a
result, no leakage will be detected.
6. Universal-head pumps
STN, SSN, STC-1.5 CN, STC-2.0 CN, STL 2.0 CN
6.1 General description
Automatic universal-head shower pumps are designed to operate
automatically in installations where the shower outlets are above
the level of the cold-water storage tank.
Shower pumps, types STN and SSN, feature independent
pressure and flow controls, with built-in non-return valves and
stainless-steel expansion tanks in each pump end. This system
ensures complete hot- and cold-water system isolation with
stable control over a very wide flow range.
Fig. 32 Definition of universal-head pumps
6.2 Dry-running protection
STN, SSN, STC CN and STL 2.0 CN universal-head pumps
feature dry-running protection to avoid damage to seals caused
by water starvation. This condition is possible if the water supply
fails, for instance if the water storage is insufficient or the pump
strainers are blocked.
If the pump runs for 60 seconds with an insufficient water supply,
the pump will stop and "lock out".
Fig. 33 Dry-running protection
Resetting the "lock out"
To reset the pump, switch off the power supply for ten seconds.
Fig. 34 Resetting dry-running protection
When the power supply is switched on again, the pump will run
for a few seconds to recharge the tanks. If it continues to run and
there is no demand, this would indicate that one of the following
situations is still present:
• No water in the system.
• Blocked strainer.
• Air which has not yet cleared.
TM05 7309 0913TM05 7311 0913
