A.O. Smith 30 User Manual
Page 15
Instruction manual SGS
15
gis
•
T
set
T
set
is the the required water temperature that has been set on the
appliance
(11.4.1 "Setting the water temperature via the SET POINT
. As soon as T
net
falls below T
set
, the water heating via the solar
heating system is started, however, only if the temperature of the heating
fluid (S
1
) is a certain (adjustable) value higher than the temperature
measured at the appliance (sensor S
2
). As soon as (T
net
= T
set
= T
solar limit
),
heating via the solar heating system is stopped. There is one exception to
this rule, and that is when T
solar limit
is set to a higher value than T
set
.
•
Hysteresis
The moment T
net
falls below (T
set
- T
solar diff
- Hysteresis), the controller
registers such a heat demand that the gas burner and the solar heating
system jointly heat the water. The solar heating system is only employed
when the temperature measured by S
1
is a certain (adjustable) value grater
than that of S
2
.
•
T
solar diff
When T
net
exceeds (T
set
- T
solar diff
), the gas burner is shut off and the water
is heated exclusively by the solar heating system. When T
net
rises above
T
set
(provided
Tset
= T
solar limit
), the solar heating system switches off. The
value of T
solar diff
is adjustable
(12.8.5 "Setting the solar difference")
•
T
solar limit
Preset
(12.8.4 "Setting the solar limit temperature")
water temperature at
which heating via the solar heating system is stopped.
Graphical representation of heating cycle
Note
T
net
can rise above T
set
,. However, this is only possible if T
solar limit
is
increased via the service menu.
Note
T
solar limit
can be lower than T
set
; this will mean that T
net
can never be equal
to T
set
.
Legend
A = Gas burner on
B = Gas burner off
T
net
:
•
= no heat demand, so water
not heated
•
= water heated via solar
heating system
•
= water heated via solar
heating system and gas burner
t = time
T = Temperature
45
o
C = Minimum tap water
temperature
T
solar limit
T
set
Solar diff.
Hys.
T
min = 45 C