Frost Protection For The Plant - Siemens SIGMAGYR RVP540 Basic Documentation

Exception
278/348
Siemens Building Technologies
HVAC Products
5.1.1

Frost protection for the plant

Depending on the current outside temperature, the released pumps will be activated
although there is no demand for heat.
Outside temperature
...-4 °C
-5...10.5 °C
1.5 °C...
Between -4...-5 °C, different statuses can occur. In that range, it is important which
situation had existed before:
If the temperature was previously higher (in the range of "takt"), the pump will also cycle
in the temprature range from –4 to +5 °C, and is continuously ON only when the tempe-
rature drops further.
If the temperature was previously lower (in the range of ON), the pump is continuously
running also in the range up to –4 °C and switches on / off only when the outside tem-
perature is higher.
ON
-6 -5 -4 -3
Basic Documentation RVP540 / RVP550
Description of the EXP settings
Pump
Continuously ON
ON for 10 minutes at 6-hour intervals
Continuously OFF
takt
-2 -1 0 1
Diagram
ON
takt
OFF
OFF
2 3 4
TA °C
CE1P2488en
18.10.2002