5 November 2010
Lengthy commissioning of cooling or heating systems is more or less a thing of the past. At least it is if you use dynamic valves instead of static valves to regulate water flow. Dynamic valves ensure your system is always balanced.
Instead of spending days and weeks commissioning a system, focus should be on trimming energy consumption.
When you fit dynamic components, your system automatically balances. The flow of water through the valves never exceeds the setting. No matter the load.
Many consultants and engineers will tell you that commissioning a large system can take several weeks to balance. To put it bluntly, it's a waste of time. If a cooling system for a large office block is fitted with dynamic valves to regulate the balance, commissioning and adjusting can be done in a single day.
In addition to saving the costs of lengthy commissioning, the dynamic regulation means your system saves more energy. There's no need for high pump pressure when the flow is controlled. A doubling of pump pressure causes an eightfold increase in the energy used to drive the pump. So, dynamic regulation saves you a great deal of money.
The dynamic components also ensure the system has a better Delta T. Because the system gets the flow it was designed for, energy is transferred as efficiently as possible. The more stable the temperature, the quieter the system, improving comfort and indoor environment - and using less energy.
Despite the fact that dynamic regulation is a proven and efficient technology, and despite the fact that dynamic valves cost the same as static valves, the majority of existing systems use static valve technology and they only send half the volume of water their valves were originally commissioned to send.
Flow but with half the volume of water! That is a serious factor that alters a system. But few janitors dare to turn down the pump pressure. Most maintain high pump pressure for fear of inferior performance in distant parts of the system.
This is a very wasteful way of consuming energy and utilising the system. It's expensive for you and me, and it's expensive for society and the climate in general.
I meet a lot of people who think you need different valves in a system to meet different requirements. This is simply not true. Dynamic valves function effectively in all circumstances. It makes no difference if we're talking about heating or cooling. It makes no difference if it's a district heating, natural gas or geothermal system. And it makes no difference if it's an oil-fired furnace that's distributing the water.
Think about the building janitor who is constantly badgered by residents to turn up the heating in the radiators because they are freezing. All that trouble and complaining would disappear if the building's system was dynamically regulated and balanced. And the janitor would then be free to fine-tune the system and reduce energy consumption.
Dynamic regulation is about taking the path of least resistance. It's about using as little energy as possible and saving money.
Jens Johansen, Product and Marketing Manager, Frese A/S
