Chapter hvac engineering Fundamentals: Part 1 Introduction

Equipment: Part 2
339
Figure 10.12
Water-to-water heat exchanger.
Figure 10.13
Control for water-to-water heat exchanger.
form distribution of steam throughout the coil, providing uniform tem-
peratures across the face of the coil and assisting in prevention of
freeze-up of condensate in air preheating coils.
10.13.1
Freeze protection for air
preheating coils
One of the most difficult HVAC processes is the preheating of sub-
freezing air. Many air-handling systems require large quantities of
outside air, up to 100 percent. When outside air temperatures are be-
Equipment: Part 2
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