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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the EXP settings
18.10.2002
5.42 Reset integral heat pump stage 2
•
Prevents frequent switching on / off of heat pump stage 2
If heat pump stages 1 and 2 together produce too much heat, the controller starts cal-
culating the surplus heat.
For that, the controller calculates the amount of surplus heat over time until the ad-
justed value is reached.
Setting range
Unit
Factory setting
0...500 K*min
10
As soon as the adjusted amount of surplus heat is reached, heat pump stage 2 will be
switched off.
5.43 Changeover of stage sequence
•
Same number of operating hours of the 2 heat pump stages
To ensure that the 2 heat pump stages will eventually operate the same number of
hours, the order of the 2 heat pump stages will be reversed when the time set here has
elapsed.
Setting range
Unit
Factory setting
--- / 10...990
h
- - -
--- Function
deactivated
As soon as heat pump stage 1 has reached the total number of operating hours set
here, the stage sequence will be reversed. This means that heat pump stage 1 be-
comes heat pump stage 2, and vice versa. The hours run counter of stage sequence
changeover will be reset and starts counting again.
5.44 Minimum water / brine temperature
•
Prevents uneconomical heat pump operation
If the water / brine temperature drops below a certain level, heat pump operation be-
comes uneconomical and risk of icing occurs on the evaporator. To ensure that the
heat pump’s coefficient of performance does not fall below a certain level and that icing
will be prevented, minimum limitation of the water / brine temperature must be pro-
vided. This is accomplished via this operating line.
Setting range
Unit
Factory setting
--- / -20...20
°C
3
--- Function
deactivated
If the water / brine temperature drops below the adjusted value, the controller will
switch the heat pump off. If the water / brine temperature exceeds the adjusted value
by one switching differential (operating line 426
EXP
), the heat pump will again be re-
leased for operation.
Benefit
Description
Setting
Effect
Benefit
Description
Setting
Effect
Benefit
Description
Setting
Effect
