4.0 ‘Intelligent Pre-heat’ Feature
7
© Baxi Heating UK Ltd 2009
Operation of Pre-heat
1. The boiler incorporates an intelligent pre-heat feature
that will ensure optimum domestic hot water
performance.
2. This features ‘learns’ the domestic hot water demand,
and pre-heats the boiler primary circuit (main heat
exchanger, pipework within the boiler case and
domestic hot water heat exchanger) in anticipation of
further demand at the same time on the next day.
3. The feature works on a 24 hour basis. If for example
there is a demand for hot water at 7:00 AM on Monday,
the pre-heat will operate at 6:50 AM on Tuesday for 1
hour. Similarly if there is a demand at 9:25 PM, the pre-
heat will operate at 9:15 PM the next day, again for 1
hour.
4. If on Tuesday at 7:00 AM there is no hot water
demand there will be no pre-heat on Wednesday at this
time.
5. The feature also operates for one hour after each
demand to maintain the temperature of the boiler.
6. There can be up to 24 pre-heat operations in a 24
hour period. While operating in the pre-heat mode the
boiler will fire up briefly 3 or 4 times in the hour to
maintain the boiler at temperature.
7. During the pre-heat period the domestic hot water
indicator will flash (Fig. 6).
8. The pre-heat feature will not operate if the DHW
Temperature Control is turned fully anticlockwise
(Fig. 4). In this position the boiler will operate as a
conventional combination boiler, providing hot water at
50° C.
9. Once the Temperature Control is turned
approximately 30° clockwise (Fig. 5) the pre-heat
feature is activated.
10. Bewteen 30° and fully clockwise the hot water
temperature can be altered from 40° and 60° C.
30°
Fig. 4
Fig. 5
Pre-heat Off
Pre-heat Activated
Fig. 6
4.1
