hose with 1/4″ (7/16-20) Female flare on manifold connection and 5/16″ (1/2-20) Female flare angled on service end

The Air-Conditioning, Heating and Refrigeration Institute (AHRI) has developed a standard (AHRI 550/590 Standard) that defines the Integrated Part Load Value (IPLV) as a better performance characteristic for chillers. Over the lifetime of a chiller, it is running at 100% capacity only 1% of the time, or in other words, 99% of the time it is at part load conditions.

The IPLV is calculated using the efficiency of the equipment while operating at capacities of:

• A = EER @ 100% Load
• B = EER @ 75% Load
• C = EER @ 50% Load
• D = EER @ 25% Load

The allocation of time running at these four loads defined by AHRI is as follows:

A=1%, B=42%, C=45% and D=12%

IPLV = 1%A + 42%B + 45%C + 12%D

Heat pump heating technology is starting to pop up more and more lately, as the technology becomes cheaper and public awareness and acceptance improves. Touted as a greener residential heating system, they are rapidly gaining popularity, at least in part due to various government green policies and tax breaks.

[Gonzho] has been busy the last few years working on his own Arduino Powered Open Source heat pump controller, and the project logs show some nice details of what it takes to start experimenting with heat pumps in general, if that’s your game. Or you could use this to give an old system a new lease of life with an Arduino brain transplant.

You can build your own "tube-in-tube" heat exchangers. It's not hard. Cheaper. The heat exchange efficiency is worse. No oil return problems. Very easy soldering. Heat exchanger math: 0.7..1.5 m2 of a copper tube per every 3kW of heat transfer.

24,000 BTU (2.0 Ton) 21 SEER Three Zone Ductless Mini-Split Heat Pump System

Outdoor models AOU18RLXFZH, AOU24RLXFZH and AOU36RLXFH allow you to connect 2 to 5 indoor units, depending on the outdoor unit selected. These systems provide both heating and cooling for year-round comfort. //

The Inverter component allows the outdoor unit to vary its speed and output to match the required capacity of the indoor unit. Thus, the Inverter model can achieve 30% more operating efficiency than conventional models and therefore, is much less expensive to run. //

The XLTH outdoor units are engineered to operate in temperatures down to -15°F, lower than any other mini-split available today. These outdoor units also include base drainage holes, a large heat exchanger, and a high capacity compressor.

A Boston professor created an invention that reflects the heat off of rooftops and even sucks the heat out of homes and buildings - and the real kicker is that it is 100 percent recyclable.

Yi Zheng, associate professor of mechanical and industrial engineering at Northeastern University, created "cooling paper" so that a building or home could essentially keep cool on its own, with no electricity required, according to Northeastern University's blog.

The paper can cool down a room's temperature by as much as 10 degrees Fahrenheit - a game-changing alternative to air conditioners that require a lot of electricity and money from home owners. //

Zheng's invention works through the "porous microstructure of the natural fibers" inside the cooling paper, which absorbs warmth and reemits it away from the building. The cooling paper itself is made out of common paper.

The light-colored material is part of Zheng's studies into nanomaterials. His idea was first sparked after seeing a bucket full of printing paper. //

Zheng and his team used a high-speed blender from his home kitchen to turn the paper into a pulp and mixed it with the material that makes up Teflon.

The product can coat buildings and homes, reflecting solar rays away from the interior and even absorbing heat from cooking, electronics and human bodies out of the indoor space.

Even when the paper is recycled, it still performs as well as the original. ///

Nice, but saying that it cools buildings is somewhat misleading: it can cool buildings below the temperature they might otherwise be without it, but it can't cool it below ambient temperature, which is half the point of air conditioning. The other half is reducing humidity, and it does nothing for that.

What this could well do is make existing air conditioning more efficient, and that is a worth doing.

Pfizer's new vaccine has to be stored at extremely low temperatures. Here's how things work when it gets that cold.

Learn how to design chilled water systems that meet the thermal comfort demands and achieve operational and energy efficiencies
Learn about the impact of pumping schemes and plant optimization of chilled water systems.
Understand how and when to consider a waterside economizer.
Review how and when to deploy a heat recovery chiller.

Fact sheet with information homeowners need to know about having a home air conditioning serviced or replaced, in light of the HCFC phaseout.

Provides information for homeowners about purchasing, maintaining, and disposing stationary refrigeration and air-conditioning equipment.

Adding better filters to my AC/heat mini split system is one of those win-win projects. Two boxes checked. First, the air in the shop will be cleaner which means I will be breathing less harmful small particles. And second, the amount of dust that makes its way onto the internals of the mini splits will be reduced and therefore reduce environmental maintenance. Prior to this article and video I completed two of the three filter boxes.

Insitu® Spray Applied Coating is a water-based and water-reducible synthetic flexible polymer anti-corrosion coating specifically designed for the protection of HVAC&R coils and components. Insitu® Spray Applied Coating contains ES2 (embedded stainless steel pigment) technology, an anticorrosion coating specifically designed for the protection of coils mounted in corrosive areas. HVAC&R coils, components, and cabinet will have a permanent, water-based synthetic coating with ES2 pigment applied to all coating surface areas without material bridging between fins. ES2 pigments are therefore suitable for even the most corrosive environments and will maintain their appearance after many years of exposure.

The coating process will ensure a uniform dry film thickness of 0.6- 1.2 mils and meet 5B rating crosshatch adhesion per ASTM D3359- 93.

Corrosion durability will meet a minimum 5,000 hours salt spray resistance per ASTM B117.

• Environmental friendly – water based, non-flammable, non-toxic
• Extremely effective adhesion on metal surface and easily air-dried
• Reapplicable
• Improves airflow and heat exchanger performance
• Very thin deposited film (< 10 micron)
• UV resistance, antimicrobial, and coil block prevention
• ASTMB117NeutralSaltSprayTest(≤ 10,000hrs)
• ASTM G85 Modified Salt Spray Test (≤ 3,000 hrs)
• ASTM G21-Antimicrobial & G22-Fungi resistance tests (PASS)
• ASTM 5894 UV Resistance (PASS)

$123, incl plastic case

The compound gauge – located in the left hand of HVAC gauges

The compound gauge is mounted on the left side of the air conditioning gauges. The compound gauges allow the HVAC technician to measure both pressure. The pressure above atmospheric pressure and vacuum pressure (blow atmospheric pressure).

Gauges are used to read the pressure of various liquids and gases in a cooling system, as well as vacuum pressure when you are pressure testing or charging the device. There are a number of different ports on the HVAC gauge set, also known as a manifold, and the main difference in the types of manifolds is the number of ports that you have available to attach accessories to, as well as the pressure that the gauge set can withstand, which is important when working with different refrigerants.