DanTaet a/s - Case Story: TV2 Headquarters Protected From Water Damage

TV2 Headquarters Protected From Water Damage

A computer-based system monitors the district heating installation,
shuts off the supply and raises an alarm in case of leakage

Story and photo: Jørgen Jensen

The headquarters of TV2 in Odense are crammed with technical equipment - not just for producing and broadcasting contents of the TV2 and TV Zulu channels, but also the equipment for heating, cooling and controlling interior climate around the seasons of the approx. 129,000 sq.ft. of rooms and studios occupied by the network. It is the responsibility of engineer Poul Erik Schulz to keep all non-TV technical equipment - a sizable chunk - in proper running order.

- My field of responsibility includes power and electricity, cooling, heating, emergency generator, sanitary, safety and alarm installations plus maintenance of buildings and outdoor areas.
Many rooms are equipped with conditioning systems to ensure temperature and in some cases also humidity remain constant all year.
A major part of the network's electrical power consumption dissipates as heat, and consequently our district heating demand is modest, says Poul Erik Schultz.

The DanTaet Leakage Protection System at TV2 in Odense monitors the flow in the district heating installation. The control unit is wall-mounted, and connected by cables to its flow meters and valves in the forward and return flow pipes.

It should be noted that part of the TV-technical equipment is critical, and the network will suffer blackout if the cooling system fails for just half an hour - provided no action is taken to rectify the situation.

Substantial amounts of energy are used in the former cattle auction. The TV2 headquarters consume over 4 MWh of electrical energy annually, a major part of which is used for cooling purposes in the summer. Outdoor climate is helping in the winter, where part of the cooling system idles as a consequence.

A pipe fractured - no water damage resulted

The cooling system is used for indoor conditioning as well as for cooling technical equipment. The cooling medium used is plain water, which feeds radiators in the ventilation system that provides an air inlet temperature between 17 and 21 °C. Condensers are mounted on the roof, where outside air cools the freon of the closed cooling circuit.

All in all 18 ventilation systems are humming in the former cattle market, and a while ago frostbite fractured a radiator in a section housing part of the TV technical installations. Nothing happened, however, thanks to the DanTaet leakage protection system, which was originally installed when the network moved in sixteen years ago.

- Of course a little water escaped, as the system is so large. From detection of the leakage until the valves are fully closed some water will inevitably escape in larger systems, but the damage is limited and contained by the protection system, explains Poul Erik Schultz.

- In large systems, subdivision into several smaller protected circuits is a good idea, and we have this under consideration. We also employ other protection strategies; in another section we use a heat exchanger, from which only the water from the secondary side may escape in case of frostbite damage.

Possible distributed leakage protection

TV2 is used to fractures in pipes and radiators. They average five a year, caused by a combination of frostbite and corrosion, and the fractures typically occur in the bend preceding the next loop.

- We watch the installations more closely now, knowing what may happen, Poul Erik Schultz emphasises.

The added watchfulness has made leakage protection more relevant than ever, and as a further consequence, the original DanTaet system was replaced in 2003 with a brand new and more capable system sporting a modem via which the manufacturer DanTaet a/s may check system functionality and integrity at all times. The protection system is mounted in the district heating installation in the compound technical building, and consists of a control unit, two flow meters and two electrically actuated valves in the forward and return flow pipes.

In case of leakage, the valves close, and an alarm is issued to the BMS, causing the duty guard, which is always there, to intervene. The automatic monitoring is based on the assumption that a leakage must be present if forward flow exceeds return flow by more than a certain tolerance.

A number of parameters are adjustable at the control unit, including the tolerable flow difference beyond which an alarm may be issued. A flow difference may even occur by the venting of trapped air from the pipe installation. Another adjustable parameter determines the time which may elapse from detection of a flow irregularity until alarm is issued.

Poul Erik Schultz incidentally feels that distributed leakage protection, where several smaller systems are installed in strategic locations, may in the future be required to supplement or replace the present main protection system. Considerations include initial costs, and the fortunate fact that several rooms have floor outlets, intrinsically limiting the possible damage.

DanTaet a/s specialises in leakage protection systems for large and small installations, including domestic applications. The systems are sold (in Denmark) via the standard distributors, and in many cases are also the reason the user obtains a premium discount from his insurance company.