在寒冷干燥的气候条件下，非住宅建筑的暖通空调系统主要使用送风加热和驱动风机和泵的能量。因此，热回收和对风机能量的影响是值得关注的，而冷却和水分的回收则不是一个问题。这项研究着眼于专门的室外空气系统，该系统采用绕线循环热回收或焓轮热回收。在非住宅建筑中，全容量热回收仅在一年中的一部分时间使用，但它仍然会导致全年空气处理机组的压力下降。在这种情况下，如果考虑到风扇能量的损失，最节能的系统并不总是温度效率最高的系统。如果将电的价值与热量的价值相比较，温度效率可能就不那么重要了。在本案例研究中，温度效率最低的焓轮是系统层面上最节能的选择。 这同样适用于绕线回路系统，其中温度效率较低的绕线回路产生的效果更好。对于绕流回路系统，有不同的液体流量容量控制策略，以获得最佳运行。常见的替代方案是通过分流组实现恒定流量和可变温度，以及通过双向阀实现可变流量。一种更节能的方法是变速泵的直接流量控制。在直接流量控制中，使用的泵功率比阀门控制小得多。尤其是分流组，其泵功率恒定且不受实际需求的影响。根据三个月内直接流量控制的绕流回路系统的测量结果进行的计算表明，优化流量后的泵功率可降低80%。引文:ASHRAE会议论文，2010年，第116卷，pt。新墨西哥州阿尔伯克基2号

Heating of supply air and drive energy to fans and pumps predominate the energy use of HVAC systems in non-residential buildings in cold, dry climates. Hence heat recovery and the effect on fan energy is of interest whereas recovery of cooling and moisture is less of an issue. This study looks at dedicated outdoor air systems with a run-around loop heat recovery or an enthalpy wheel heat recovery. In nonresidential buildings heat recovery with full capacity is used only during a part of the year but it still causes a pressure drop in the air handling unit all year round. In this situation the most energy efficient system is not always the one with the highest temperature efficiency if one considers the penalty in fan energy. If the value of electricity, compared to the value of heat, is taken into account, the temperature efficiency might be even less important. In this case-study the enthalpy wheel with the lowest temperature efficiency was the most energy efficient choice on a system level. The same applies for the run-around loop systems, where the run-around loop with the lower temperature efficiency gave the better result.In the case of run-around loop systems there are different strategies for capacity control of the liquid flow to obtain optimal operation. Common alternatives are constant flow with variable temperature by means of a shunt group and variable flow by means of two-way valve. A more energy efficient way is direct flow control of a variable speed pump. In direct flow control a much smaller pump power is used compared to valve control. Shunt groups, in particular, result in pump power that is constant and unaffected by the real demand. Calculations based on measurements on a run-around loop system with direct flow control during three months show that the pump power after optimizing the flow can be reduced by 80 %.