The company reserve the right to alter size, shape and specification without prior notice
Page 17
Termo E boilers are supplied with a full range of curves to choose from.
The choice of a heating curve is dependent on the insulation levels in the building. Heating curves can be altered
at any time by the householder, but once correctly set, should never require adjustment. The best guide to
insulation levels is the age of the building, as insulation levels have steadily improved over time. The factory set
heating curve is for buildings built to 2000 building regulations and UK heating installation common practice.
The table below shows the suggested heating curves for properties of differing ages. If extra insulation has been
retro-fitted to a building, a lower heating curve will be appropriate.
4.3.2. To set correct curve
Turn central heating
on
(key 7).
Press key 6 UP and hold for five seconds
to enter curve selection menu. The set
curve blinks in the display. Press key 6 up
or down to alter curve selection in steps of
0,1, see the diagram on the front plate. If
there is no pressure on the key for more
than 5 seconds the curve displayed is
saved.
Construction date
Radiator curve
under floor curve
Pre 1970
2.0
0.9
1971 – 1990
1.8
0.8
1991 – 1999
1.6
0.7
2000 – 2005
1.5
0.6
2006
1.2
0.5
Factory default
1.5(mod)
0.6(mod)
Factory default curves have been modified specifically for UK heating design standard practice. If curve is altered
and default curve is then subsequently required, a factory reset is required. See instructions page 25.
4.3.3. Setting internal temperature
Heating curves are factory set to achieve a 22°C room temperature.
Should the temperature required differ from this, the primary temperature should be raised or lowered (offset) 3°C
for every 1°C higher or lower required as room temperature. e.g. if 20°C room temperature is required, the
primary temperature should be lowered by 6°C.
Offsetting the heating curve will change the temperature of the water in the boiler without changing the shape of
the curve. See diagram above.
To offset the curve
. Press key (6)
down
and hold for 5 seconds to enter offset curve selection menu
The set offset in ˚C blinks in the display. Press key 6 up or down to change offset in steps of 1˚C. If there is no
pressure on the key for more than 5s shown value of offset in ˚C is saved.
Factory setting is 0˚C. Offset range is from –9 to +20˚C.
Please note that Thermal (heating) processes are slow, and the impact of alterations will not be felt immediately.
Oso recommend that adjustments are given at least 24 hours to take effect.
It is also recommended to make a log of all adjustments made and their result. This will assist in making accurate
alterations in the future.
If settings as described above are not adequate for achieving the wanted room temperature, supplemental
adjustments of the heating curves and offset can be made by the user. See table below
Conditions experienced
Curve selection
Offset
(radiator heating)
Offset
(UFH heating)
Room temperature is too low
if the external
temperature is
above + 5
o
C
Lower curve by 0.1
Add with offset
+ 6
o
C
Add with offset
+ 4
o
C
Room temperature is too low
if the external
temperature is
b 5
o
C and - 5
o
C
Leave the curve
Add with offset
+ 3
o
C
Add with offset
+ 2
o
C
Room temperature is too low
if the external
temperature is
under - 5
o
C
Higher curve by 0.1
Leave offset
0
o
C
Leave offset
0
o
C
Room temperature is too high
if the external
temperature is
above + 5
o
C
Higher curve by 0.1
Lower with offset
- 6
o
C
Lower with offset
- 4
o
C
Room temperature is too high
if the external
temperature is
b 5
o
C - 5
o
C
Leave the curve
Lower with offset
- 3
o
C
Lower with offset
- 2
o
C
Room temperature is too high
if the external
temperature is
under- 5
o
C
Lower curve by 0.1
Leave offset
0
o
C
Leave offset
0
o
C
4.3.4. Programmable room thermostats & setting variable internal temperatures
Central heating is controlled by the heating curve programmed into the Termo E boiler and fine tuned by a room
thermostat.
With modern central heating controls such as a programmable room thermostat it is possible to set different room
temperatures at different times of the day. e.g. to have a lower temperature set during the night. If this system is
used the heating curve selection is unchanged and the offset of the heating curve should be set to the highest
room temperature required during the day. (See paragraph above). The programmable room thermostat is then
set according to the manufacturers instructions to set lower temperatures when required.
