How does a rawal valve or hot gas bypass work?
In some cases, it benefits the system to incorporate some means of false-loading on the compressors. Both Rawal valves and Hot Gas Bypass provide a solution for this. In both cases, we’re able to trick the compressor into staying on-line even if we do not have the load in the space. This keeps your coil […]
Helpful Equations Part 1
Here are a few helpful equations that we’ve found helpful through the years. Future posts will build on this list, and the back of our line card will have a summary of them all. Cooling tonnage: TONS = ((evap gpm) x (evap ΔT)) / (24) *assumes evap ΔT in degrees F, and 100%water Efficiency conversion: […]
Using Modular Chillers in Variable Flow Applications
Modular chillers offer a unique set of advantages to conventional machines – which we’ll cover in a future post. The focus here will be on incorporating a modular chiller in a variable flow system. We will touch on the basics here. More information can be found in the links below, or by contacting NEAP directly. […]
Understanding AHRI 920-2015 and MRE (Moisture Removal Efficiency)
Understanding the basics of ANSI/AHRI 920-2015: Performance Rating of DX-Dedicated Outdoor Air System Units DX-Dedicated Outdoor Air Systems (DX-DOAS) condition outdoor ventilation air independently from the building HVAC System. This approach to handling ventilation air results is superior humidity control by limiting the primary source of humidity in most buildings – ambient humidity carried in […]
Sound POWER vs Sound PRESSURE – what’s the difference?
Most the folks we work with are not acoustical consultants. But most of the projects are influenced by the sound that equipment creates. Understanding how HVAC equipment sound is measured and conveyed is important – and at the very core is the understanding of sound power vs sound pressure. One of the easiest ways to […]
Dedicated Heat Recovery Chillers (DHRC)
Dedicated Heat Recovery is not a new topic. In 2003 ASHRAE published an article detailing the technology and advantages of dedicated heat recovery chillers (DHRC) – see link below. However, these systems become increasingly beneficial with the advent of modular chiller design, and a packaged controller capable of staging the compressors based on the lower […]
United CoolAir – Minimizing Install Time & Costs @ Custom House Boston
United CoolAir provides a complete line of indoor self-contained units. Ranging from 1 to 70+ tons – they provide total indoor solutions for water-cooled, air-cooled, heat pump and ducted split systems. The modular solution shown in The Custom House video allows for installation in extremely tight spaces. The quick-connect refrigerant fittings and pre-charged modules allow […]