Instructions for designing heating systems

Pressure control of pumps

All the circulation pumps in systems with varying flow should be equipped with pressure control. A constant differential pressure at the last branch/valve provides the largest saving.

Using pressure control doesn’t mean that differential pressure control valve should be excluded.

Control of the available differential pressure

In buildings of maximum 6 floors, each riser is equipped with a differential pressure control providing 10 kPa. When the building has more than 6 floors, a differential pressure control, providing 10 kPa, should be installed on each floor.

Flow metering per apartment / Heat

Each apartment is equipped with a flow meter for the distribution of the heating costs. The flow meter should be accessible for reading from the stair-well, and possibly connected with the control and supervision system of the building. With regard to gable apartments and apartments with a roof, a compensating factor is calculated on the basis of heat requirement calculations made for a similar apartment in the centre of the building.

Domestic water system.

Domestic hot water is produced in a heat exchanger of the percolation type in the sub-station. A distribution pipe is laid in the ground floor of the building, from which risers are drawn up centrally through the building. Each riser is equipped with shut-off and draining valves.

The branches on each floor are equipped with shut-off valves. Distribution pipes and risers should be made of a non-corrosive material and well insulated. A gravity pipe for the of hot water should be laid parallel to the tap water
pipe.

The circulation pipe should be laid uninsulated in the riser, and at the connection with the horizontal circulation pipe be equipped with an adjustment valve. Flow meters for domestic hot water should be installed in the stair-well,
one for each apartment.