Arotherm plus

arotherm plus, brand new install, getting following challenges (arotherm plus, 97/6 , HEX 150, underloor heating plus DHW cylinder)

  1. which circuit diagram is best to suit HEX and hydraulic station with underfloor heating 1 zone, 1 DHW ?
  2. how to change target floor temperature? whatever i do is always 0
  3. how to force DHW and heating to run in parallel? whatever i do with 720 , runs only one at a time. (great engineering, never again german made)
  4. how to fix F.1100 ? if system is designed to run 75degree max, how 95degree possible to blew up fuse for cut off? who did come up from engineering department with that wonderful idea? none could install 50cent fuse instead of expensive cut off thermostat replacement.

appreciate help

For most systems a HEX plate heat exchanger, buffer tank or low loss header are not needed. If possible ask your installers to design out the need for hydronic separation by removing the pump on the UFH manifold. This will improve the efficiency by removing the possibility for distortion, reduce heat loss and the need to have two pumps running.

DHW and central heating cannot run at the same time, the system will swap between the two via a diverter valve. Usually DHW recharge only takes about 30min.

The immersion heater should not be needed with a Vaillant heat pump, you should be able to safely switch it off.