Tuesday, September 30, 2008

Factory Set Superheat



Our thermostatic expansion valves are factory set to a specific superheat. If adjustment is needed, refer to superheat adjustment instructions for proper procedure. Kindly check with your local Emerson Flow Controls wholesale specialists for step-by-step guide.

Improper adjustment may result in valve malfunction and /or system damage.

Saturday, September 27, 2008

Measuring Superheat


Where possible, always select a thermal expansion valve for the actual operating conditions rather than nominal valve capacities.

To determine the valve is working properly is by measuring its superheat.

The degree to which the refrigerant gas is superheated depends on
1) the amount of refrigerant being fed to the evaporator by the valve
2) the heat load to which the evaporator is exposed.

Thursday, September 25, 2008

Service Instructions for Take-A-Part Thermo Expansion Valves

Before opening any system, make sure the pressure in the system is brought to and remains at atmospheric pressure. Failure to comply may result in system damage and /or personal injury.
To inspect, clean, or replace parts of the Thermo valve:-
1) Disconnect equalizer line
2) Remove cap screws
3) Carefully lift off the power assembly
4) Remove cage assembly and gaskets
5) Lightly oil gasket with refrigeration oil

Best practice: Replace all gaskets whenever a valve is opened.

6) Assemble in the same order as disassembled
7) When putting the power assembly on, make sure the cage assembly lugs line up with the slots inside the power assembly
8) Tighten cap screws evenly and torque to 300 inch pounds
9) Check for leaks

Wednesday, September 24, 2008

Superior filtration for greater refrigeration protection

The Extra Klean EK Filter Drier
Get a bead on superior contaminant protection

When it comes to the refrigeration systems you install and maintain, what matters most? It is keeping them running at peak efficiency. Keeping your reputation intact and your customers satisfied. It is choosing superior filtration technology that delivers more reliable, longer-lasting protection from moisture and contaminants.

The EK Filter Drier offers unprecedented operational flexibility. It’s an ideal solution whether you’re using HCFCs, CFCs or newer HFC refrigerants. In fact, the EK Filter Drier is Copeland recommended for HFCs such as R-410A. Its beaded desiccants protect new POE oils from contaminants and quickly absorb and remove any moisture before acids can form. And there are a variety of available models to meet any system demand.

More information here.

Thursday, September 18, 2008

Oil level monitoring controls


Maintaining proper oil level is of primary importance for a long compressor lifetime. Especially when paralleling compressors in compressor pack applications, maintaining sufficient oil in the compressor’s crankcase becomes difficult. A simple way of balancing the oil level in parallel compressor arrangements is the use of oil equilibrium lines. These systems are also referred to as passive systems. However, passive systems require individual tailoring for each application and they only perform satisfactorily under more or less constant operating conditions. Particularly in refrigeration applications with varying operating conditions and defrost cycles an active means of oil level management is a must in order to ensure reliable compressor operation. An additional benefit of active systems is that, apart from oil balancing, they normally also monitor the oil level and provide alarming capabilities. This is a particular benefit for scroll compressors which, due to the lack of an integral oil pump, do not have a differential oil pressure switch as conventional compressors have. The OMB is a self-contained system which provides both functions, oil level monitoring and oil level balancing, for active oil level management systems. The OMB system is applicable to low and high pressure oil management systems. Traditional oil level management systems work with a low pressure oil reservoir. The oil is kept at a pressure slightly above suction pressure by a differential pressure valve.

Look here for high efficiency oil separators for your systems.

Tuesday, September 16, 2008

Specify the Emerson oil controls solution.


When it comes to managing refrigeration systems, one of the main concerns is to keep the compressor lubricated while maintaining a high level of heat transfer and energy efficiency by removing as much oil as possible from the refrigerant. This requires sophisticated oil management devices. Emerson Climate Technologies offers a complete range of premium quality mechanical and electronic oil control devices aimed at keeping your refrigeration systems at peak performance at all times. A-WC/A-FC series centrifugal oil separators feature higher oil removal efficiency and lower pressure drop than the leading competition, according to independent test lab results. The OMB electronic oil level control employs Reverse Hall Effect sensing technology to precisely determine the compressor crankcase oil level and feed oil exactly when needed. Its five times lockout feature provides extra protection to the compressor. Specify Emerson again & again! Install confidence everytime and for every jobs!

Friday, September 12, 2008

Specify the Emerson system protectors solution.


When it comes to the refrigeration systems you install and maintain, what matters the most? It’s keeping them running at peak effi ciency. Keeping your reputation intact and your customers satisfi ed. It’s the kind of protection you can only get from the established industry leader, Emerson Climate Technologies. Our EK filter driers, HMI hermetic moisture indicators, along with many other high performance products, provide you with a total package that delivers more reliable and longer lasting protection from moisture and contaminants. Come see for yourself what the total package is all about. Specify Emerson for every jobs! Install Confidence!

Thursday, September 11, 2008

What makes Emerson’s moisture indicator better? Early detection

The 3% difference.
What makes Emerson’s moisture indicator better? Early detection. The HMI’s patented wafer dial uses a three-step gauge to detect moisture at 3% relative humidity (RH) – giving you plenty of time to make necessary adjustments before any damage is done. Ordinary indicators use a two-step paper gauge that only detects moisture at 10% RH – a level that is more than enough for corrosive acids to build up and totally destroy a system.

Designed for today. Made for tomorrow.
The added moisture sensitivity of the HMI makes it ideal for nearly every refrigerant available – from HCFCs to new higher-pressure HFCs (including R-410A). In fact, the HMI is available with both ODF and SAE connections and is the only moisture indicator UL-approved to 680 psig. So even as your customers’ systems undergo mandated changes in the next few years, the HMI you install today will work with the refrigerants of tomorrow.

Built to last with a universal fit.
The HMI has an airtight, corrosion-resistant brass body with no o-rings or knife-edge seals for guaranteed leak-free operation. Plus it is heat resistant, so you can braze without having to worry about damaging the internal wafer dial. For installation, the HMI features solid copper fittings for easy, universal replacement of any brand indicator. Saving you time, along with your reputation.

Now you see it. Now you know.
Let’s face it, moisture indicators are almost always in dark areas with poor light. Which is why we gave the HMI a wide-angle, .71 square-inch viewing lens – by far the biggest in the industry. And with an easy-to-read tri-color-coded system, you’ll be able to read the dial even in low light.

Paper or plastic?
The HMI wafer dial is a molded disk that is significantly more durable than ordinary paper indicators. And it is more sensitive to lower levels of moisture (3% versus 10% relative humidity). In fact, the color in a paper indicator can actually wash out under wet conditions. Plus paper indicators are highly susceptible to damage from brazing during installation.

Protect your reputation with the HVAC/R technology leader.
When it comes to your HVAC/R systems, you have enough things to worry about. Your reputation shouldn’t be one of them. With Emerson’s HMI, you know your customers are getting a better indicator and you are getting a better warning system. After all, your reputation is worth it.

Lets look at the review from http://www.achrnews.com.

Earlier indication.
Better design. More reliability. The Emerson Climate Technologies Hermetic Moisture Indicator. Buy yours from our selected wholesalers.

Tuesday, September 09, 2008

HFC Refigerants and POE Lubricants - Part 3: How to combat water in the system [2]?

Another aspect of POE oil is the ability to keep more solid particles in suspension than Mineral oil. This is particularly important in retrofitted systems where pockets of solid contamination are now flushed from low flow areas and need to be removed before moving parts in the system are damaged. The filter-drier for POE oils needs to have increased solid particle holding capacity with minimal impact to refrigerant flow capacity or pressure drop.

The filter-drier should also have improved contaminate removal efficiency as well to ensure that all particles are captured the first time they enter the filter-drier. The ability to remove smaller particles is also advantageous. The EK series filter-driers provide a unique combination of these characteristics to provide outstanding filtration.

The filter-driers for use in HFC and POE oil systems must maintain the system dry and free of any acids that may have been generated. However, since water capacity is of primary importance the filter-drier should contain a higher percentage of molecular sieve than was required for CFC and HCFC systems. But molecular sieve alone is not sufficient since it has virtually no organic acid capacity. An organic acid removal desiccant must be used such as activated alumina to ensure low acid levels are maintained. In addition, the filter-drier should also have increased filtration capacity and efficiency.

The EK filter-driers provides the optimal combination of these properties to ensure the long, trouble free life of any air-conditioning or refrigeration system.

The moisture indicating sightglass must also indicate moisture level in the range of less than 50 ppm moisture. Also, it must be able to perform this function at the temperature of the liquid line on which it is placed. Many sightglasses cannot perform this function at all liquid line temperatures. This low level indication ability is necessary to ensure that the system moisture never exceeds the level at which organic acid formation starts. The HMI & AMI moisture indicating sightglasses provide this low level detection early.





Monday, September 08, 2008

HFC Refigerants and POE Lubricants - Part 2: How to combat water in the system [1]?

Refrigerant systems must be dry internally because high moisture content can cause ice to form in the expansion valve or capillary tube, corrosion of bearings, reactions that affect lubricant / refrigerant stability, or other operational problems. As with other components, the refrigeration lubricant must be as dry as practical. Polyolesters [POE] usually contains 50 to 100 ppm moisture in normal manufacturing. This amount may increase between time of shipment from the refinery and the time of actual use.

POE oils are quite hygroscopic in its properties.

Monitoring

To combat the detrimental effects of water in HFC and POE systems it is imperative to hold moisture levels as low as possible. It is generally accepted that water level must be maintained less than 50 ppm in the refrigerant and the same for the oil. Monitoring is therefore necessary. In order to monitor system water level a moisture indicator must be used that can sense changes in moisture in this ppm range.

Many commercial sightglasses cannot indicate a change at this level in liquid lines that exceed 100degF or 38degC. This means that harmful organic acids may be attacking system components while the indicator is showing 'dry'. The HMI and AMI moisture indicators have unique element that has the ability to change colour at low ppm levels so that proper action can be taken before any system components are damaged.

Filtering

Because POE lubricants are quite hygroscopic, when they are in a refrigeration system they should circulate through a filter-drier designed for liquids. A filter-drier must be installed in the line carrying liquid refrigerant or in a line returning lubricant to the compressor. The desiccants will remove some additives in the lubricants. It was necessary to redesign standard 'catch-all' filter-driers for increased water removal capacity to achieve these low moisture levels. Since no system is entirely devoid of water upon startup some organic acids will be generated and must be removed.

The desciccant formulation for the EK and UDK series of filter-driers was designed to provide the optimal mix of water capacity and acid capacity to ensure that both harmful contaminates are effectively removed. This desiccant mixture contains both molecular sieve and activated alumina. The molecular sieve is specially designed to provide maximum drying in today's systems. The activated alumina is ideal for capturing the large organic acids that the molecular sieve cannot.

Friday, September 05, 2008

HFC Refigerants and POE Lubricants - Part 1 : Why is it important?

The use of HFC refrigerants and Polyester [POE] lubricants for air-conditioning and refrigeration have generated new system chemistry related problems. New and redesigned system protectors have been developed to counteract these problems and provide a long, reliable life for the operating refrigeration system.

Moisture is the major problem causing contaminate for HFC/POE oil systems just as was for CFC and HCFC systems using Mineral oil. Many HFC's can hold much more water than their CFC counterparts but the oil differences are much worse than those of the refrigerant. POE oil can hold as much as 10 times more water than Mineral oils. In addition, evacuation has proven ineffective at removing this moisture so as a filter-drier is required to perform this function.

Water poses a new problem for POE oils above and beyond those experienced with Mineral oil. POE oil will react with water to form organic acids at normal operating conditions in refrigerating and air-conditioning systems. This reaction starts at water levels as low as 75ppm. These acids attack system components including motor insulation and metallic components --- reducing system life.

Thursday, September 04, 2008

Advantages of EX Series Electrical Control Valves

The electrical control valves EX4, EX5, EX6, EX7 and EX8 from Emerson are optimized for control of liquid or gaseous mass flow in refrigeration systems. The stepper motor drive, which produces exact valve opening, is energized directly from the electrical power and therefore operates independently from differential pressure.



EX series electric control valves can operate from 2kW to 880kW (For R22).

Wednesday, September 03, 2008

Viewing lens / HMI moisture indicator


Moisture indicators on refrigeration equipment are critical early-warning components in the effort to lessen the long-term effects of water damage and reduce repair and maintenance costs. The proper moisture indicator must sense and report just how much water is in the system’s circulating refrigerant. An indicator in a viewing lens changes color as the moisture content reaches potentially damaging levels. Be sure to choose an indicator that is sensitive enough to alert operators early on that moisture levels are rising, allowing corrective action to be taken before serious system damage occurs. The Hermetic Moisture Indicators (HMIs) from Emerson are able to read moisture levels far below industry standards. The HMI actually begins to change color at two percent relative humidity (RH), which is a “very dry” indication. At 3% RH, the purple caution color begins to appear. Many other indicators do not begin changing colors until about seven to eight percent RH; however, early detection is critical with HFC refrigerants and POE lubricants. POE oil can hold up to 20 times more moisture than the mineral oil used by older refrigerants, which can allow corrosive acids to build up and totally destroy a system. The HMI is UL listed with a 680 psig maximum working pressure, making it acceptable for use with higher-pressure HFC refrigerants. It has a larger viewing window for easier visibility and charging. It is resistant to “washout” from water and can withstand brazing temperatures up to 450 degrees Fahrenheit [ 232 degree C]. The fully hermetic design includes a corrosion-resistant, all-brass body with no o-rings or knife seals that are likely to leak. The indicator features solid copper fittings for easy, universal replacement.



Lets look at the review from http://www.achrnews.com.