Then different arguments why it is important the use of independent pressure valves are exposed.
by Víctor Orozco *
IP technology like that is incorporated in the valve Pressure Independent (or EPIV PICCV), combines the function of automatic balancing valve and a control valve in a single unit. The PICCV is designed to maintain a stable flow (and hence differential temperature) through a coil despite any pressure fluctuation that may occur in a typical system with multiple interactive control valves and circuits.
These types of features support the concept of Dynamic Balancing, especially applied in primary and secondary variables hydronic systems. Dynamic balancing avoids the need to continuously rebalance the hydronic system, either changes and alterations in design or installation.
Virtually any system with multiple and interactive circuits requires balancing start and routine, even those "strictly" designed. There are two fundamental reasons for this:
- First, it is very unusual for mechanical systems are designed to perfection. Most are designed (or updated) with one or more of the following flaws: serpentines not properly dimensioned, oversized pumps, pipes incorrect and need perfect authority control valves. All these elements produce pressure fluctuations that have an impact on performance and overall efficiency. Therefore, rolling (and rebalancing) is required unless IP technology is used.
- Secondly, in a system Normal pressure fluctuations as a result of the constant load changes due to air temperatures outside occur, moisture, building occupancy, etc. While there have been some inquiries regarding the feasibility of pressure-dependent systems that do not use rolling, we do not consider this to be a realistic alternative for buildings with multiple and interactive circuits.
On the issue of efficiency and savings in distribution systems of water, we can point out that for optimal efficiency, control valves must maintain a delta T consistent throughout the coil that is in the design value or near regardless of pressure fluctuations in the system. If the delta T design is 12 ° but is only reaching a differential 6 °, then you are wasting energy (and money).
This is where PI design achieves savings by only pumping the required amount and the hydronic system design. As demonstrated by independent testing, IP technology keeps delta T design constant despite the varying conditions due to partial loads and system diversity.
Víctor Orozco's Regional Advisor for Latin America Applications Belimo Americas. He can be contacted via email Victor.Orozco@us.belimo.com