Function Description Of Solar Dhw Heating - Viessmann Solar EM-S1 Extension Installation And Service Instructions Manual

Solar EM-S1 Extension Installation / Service

Function Description of Solar DHW Heating

Parameter
Number Designation
The solar circuit pump is switched on according to the following criteria, resulting in the DHW being heated:
1126.0 "Collector minimum temperature"
1492.0 "Start temperature differential,
solar circuit pump"
The solar circuit pump is switched off if one of the following criteria is met:
1125.0 "Maximum DHW tank temperature
for solar DHW heating"
1126.1 "Maximum collector temperature"
1492.1 "Stop temperature differential,
solar circuit pump"
--
Further parameters:
1118.0
1118.1
Suppression of DHW tank reheating by the boiler
Reheating of the DHW tank by the boiler is suppressed
when the set DHW temperature for reheating is reduced
by the boiler.
Start of reheating
suppression
Stage 1
Solar circuit pump on
Stage 2
Solar circuit pump on
> 120 min
--
Duration of reheating suppression
Solar circuit pump runtime x 6
Example:
Solar circuit pump runtime: 0.5 h
0.5 h x 6 = 3 h reheating suppression
Pump runtimes that occur during the runtime of
reheating suppression are calculated according
to the formula and the result is added to the
remaining runtime of the previous reheating
suppression.
Runtime of the solar circuit pump + 24 h
Note: Set or alter the functions described below in the
parameters in the "Solar" group.
Description
The solar circuit pump is started when the minimum collector
temperature set in parameter 1126.0 is exceeded.
The temperature differential between the DHW tank temperature
and the collector temperature is greater than the start temperature
differential set in parameter 1492.0.
The maximum DHW tank temperature (set DHW temperature)
set in parameter 1125.0 is exceeded.
If the maximum collector temperature set in parameter 1126.1
is exceeded, the solar circuit pump is switched off to protect the
system components (emergency collector shutdown).
The solar circuit pump will restart when the collector temperature
falls to 20 K (36°F) below the set value.
The temperature differential between the DHW tank temperature
and the collector temperature is smaller than the stop
temperature differential set in parameter 1492.1.
The temperature set at the temperature limiter (if installed) is
exceeded.
Minimum speed of the solar circuit pump adjustable in %.
Delivered condition: 23%
Maximum speed of the solar circuit pump adjustable in %.
Delivered condition: 84%
During reheating suppression, the DHW tank is only
heated by the boiler if the DHW tank temperature falls
below the set DHW temperature for reheating.
The duration of reheating suppression is based on the
runtime of the solar circuit pump and takes place in 2 stages.
Set DHW temperature for reheating by the
boiler
Average of the set DHW temperature and the
value set in parameter 1394.0
Example:
Set DHW temperature: 122°F (50°C)
Value set in parameter 1394.0: 104°F (40°C)
Calculated set DHW temperature for reheating
by the boiler: 113°F (45°C)
Value set in parameter 1394.0
As for stage 1
Solar circuit pump running:
Solar circuit pump off:
Function
13