Add switch temperature

[kstaniek]

I have two HC and Switch (mixer). Instead of retTemp the Boiler reports switch temperature. There is external temp sensor inside the switch connected to the boiler.

Boiler stats:
  Boiler: Buderus GBx72/Nefit Trendline/Junkers Cerapur (ProductID:123 Version:04.09)
  Hot tap water: off
  Central heating: off
  Warm Water activated: on
  Warm Water circulation pump available: on
  Warm Water comfort setting: Eco
  Warm Water selected temperature: 50 C
  Warm Water desired temperature: 70 C
  Warm Water current temperature: 50.5 C
  Warm Water current tap water flow: 0.0 l/min
  Warm Water # starts: 4552 times
  Warm Water active time: 68 days 14 hours 2 minutes
  Warm Water 3-way valve: off
  Selected flow temperature: 5 C
  Current flow temperature: 43.6 C
  Return temperature: ? C  <---- this does not exist
  Switch temperature: 23.0 C  <----- this is added
  Gas: off
  Boiler pump: off
  Fan: off
  Ignition: off
  Circulation pump: off
  Burner selected max power: 0 %
  Burner current power: 0 %
  Flame current: 0.0 uA
  System pressure: ? bar
  System service code: 0H (203)
  Heating temperature setting on the boiler: 55 C
  Boiler circuit pump modulation max power: 100 %
  Boiler circuit pump modulation min power: 10 %
  Outside temperature: 7.9 C
  Boiler temperature: ? C
  Pump modulation: 0 %
  Burner # starts: 24634 times
  Total burner operating time: 330 days 17 hours 38 minutes
  Total heat operating time: 262 days 3 hours 36 minutes
  Total UBA working time: 965 days 1 hours 30 minutes

The frame:

(00:20:14.617) Sending read of type 0x19 to 0x08, telegram: 0B 88 19 00 20 (CRC=D0)
(00:20:14.701) Boiler -> me, type 0x19, telegram: 08 0B 19 00 00 4F 80 00 80 00 00 00 00 00 00 60 3A 07 44 62 00 00 00 05 C2 98 00 4E 72 00 E6 (CRC=D5) #data=27
<--- UBAMonitorSlow(0x19)

The last two bytes (00 E6) in above UBAMonitorSlow represent switch temperature.