Evaluation of systems and products

Vertical or horizontal systems

Vertical radiator systems imply that the riser is laid at an outer wall, and that one, maximum two radiators per floor are connected to the riser. There are two important disadvantages with this system. For one thing, there are many risers conducting noise between the apartments.

Secondly, when using one-pipe systems there are problems in how to limit the number of radiators per one-pipe circuit. One as well as twopipe systems can be used. There are also difficulties insulating the risers placed visually in the rooms. Horizontal radiator systems imply that several apartments on the same floor share a riser, how many depending on the planning. The riser can, in this case, be laid centrally in the house and be insulated so that all
floors obtain the same flow temperature.

The piping to the radiators is installed horizontally on a wall or embedded in the floor and can be installed separately for each apartment as well as for multiples. When using two-pipe systems, there is the possibility of metering the flow to the radiators in each apartment and also keeping the available differential pressure constant on each floor. The disadvantage is the laying of the pipes to the radiators. Horizontally laid pipes on a wall by the floor or by the ceiling are neither pretty to look at nor hygienic, and near the floor cause problems if doors are to be passed. The casting of pipes into floors requires that the floor construction is made in two steps, one bearing construction, upon which the pipes are laid and one screed laid after having pressure tested the pipes.

Embedded pipes ought to be insulated and require such conditions that they do not need to be exchanged until the building has served its time. One- as well as two-pipe systems can be used.

Centrally placed risers and horizontal laying to the radiators are advantageous, above all when constructing a new building, but this can also be made in existing buildings. Some advantages are:

• a smaller number of risers
• no noise transfer between the apartments
• the possibility of flow metering per apartment
• differential pressure control for each floor
• small radiator circuits reducing the requirement of adjusting