Compressor Rebuild | HVAC Heating and Cooling Refrigeration

Compressor Rebuild

The compressor in an HVAC refrigeration system

Compressor Rebuild - This freshly rebuilt reciprocating compressor is destined for a large commercial chiller. Chillers chill water for air conditioning. Compressors compress refrigerant vapor and pump the compressed refrigerant to the condenser to be condensed into a liquid. It is an essential component of the refrigeration system.

The compressor provides compression which is an integral part of the refrigeration process. The old compressor was condemned for electrical burnout. The windings in the old one burned up and caused the circuit breaker to trip. (more…)

HVAC Centrifugal Compressors | HVAC Refrigeration

HVAC Centrifugal Compressors

Carrier Chiller w/Air Source Condenser

HVAC Centrifugal Compressors - Centrifugal compressors are used in many applications including pipeline transport of natural gas along with many other related applications including vapor compression refrigeration. These compressors have different operating limitations than the reciprocating compressor, the scroll compressor, and the rotary compressor.

They work in an operating range where it works efficiently however outside of this range, either the over or under that operating range is basically useless. Other issues make them not ideal for use in certain applications because of the operating range issues. (more…)

Rotary Compressors | Air Conditioning & Heating Systems

Rotary Compressors

Rotary Compressors - The rotary compressor used in HVAC applications for air conditioning and heating systems offer some of the most efficient air conditioner and heat pump systems one can find on the market.

Despite the rotary compressor being a key component of an air-source air conditioner or heat pump the efficiency offered by this compressor when used as a modulating compressor can exceed efficiency ratings of some geothermal systems.

When the compressor is coupled to an inverter and the proper inverter control system the efficiency of the air-source air conditioner or heat pump system spike to match those of some geothermal air conditioner or heat pump systems.
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Refrigerant Alarm Control for Chiller Room

Refrigerant Alarm Control for Chiller Room

Refrigerant Alarm Control for Chiller Room

This refrigerant alarm serves two chiller rooms and alerts operators and other staff that refrigerant has been released into the mechanical room. Chillers have a built-in pressure relief valve that will release the refrigerant in the event too much pressure builds up in the system. This prevents a possible explosion from too much pressure and also protects the equipment from a catastrophic failure that would make the chiller unusable. (more…)

Refrigeration for HVAC | Air Conditioning and Heat Pumps

HVAC Refrigerant Pressure Temperature ChartRefrigeration for HVAC - Air conditioners and heat pumps use the process of refrigeration to provide heating and cooling. What is the definition of the process of refrigeration? Refrigeration is the process of moving heat and depending on whether it is a heat pump or air conditioner and what mode it is in will depend on where you are moving the heat. An air conditioner and a heat pump (in the cooling mode) will move heat outside. The evaporator coil absorbs the heat and the condenser rejects the heat. (more…)

HVAC Temperature Measurement Conversion

HVAC Temperature Measurement ConversionHVAC Temperature Measurement Conversion - In air conditioning and heating applications it is necessary to accurately measure temperature to offer control of the temperatures relative to the application for which the HVACR equipment is serving. There are four separate temperature scales used to measure temperature and it becomes necessary at times to have the ability to convert between the different scales.

Aside from the temperature measurement scales and their use in HVAC, there are also methods for using specific tools to make those measurements. For example, in many cases, a technician needs to know the dry-bulb temperature and the wet-bulb temperature. In the old days, a technician would use a sling psychrometer to get the wet-bulb temperature.

Today, there are digital instruments that will measure the wet-bulb temperature for the technician. Here we begin with temperature conversion:  (more…)

Old Leaking Condenser Coils

Old Leaking Condenser Coils

Old coil with HVAC Refrigerant Leaks

Old Leaking Condenser Coils (also referred to as freon leaks) can cause serious issues with HVAC heat pump equipment. HVAC refrigeration circuits are designed and built to hold the refrigerant. It is a sealed hermetic system. The HVAC refrigeration circuit should never need refrigerant. An HVAC refrigeration system does not burn refrigerant. The refrigerant is used over and over again to move heat from one place to another. Aside from a leak, once the refrigeration system is properly charged, the system should never need refrigerant for the life of the equipment. (more…)

Condensing Unit Frozen Wont Turn Off

Condensing Unit Frozen Wont Turn Off - What you can expect to learn from Condensing Unit Frozen won’t Turn Off article: this article is an answer to a question taken from our email by a visitor to High Performance HVAC. We often use the questions we get in the email as a guide to writing articles. The topic is a condensing unit that will not turn off, and it is freezing up. From my experience in the field and using my HVAC knowledge, I offer the readers a list of what could cause this problem. We hope it helps you.
What’s the possible problem with a frozen air conditioner condenser that won’t turn off except with the breaker? (more…)

Crankcase Heaters and Compressors | HVAC Refrigeration

Crankcase Heaters and Compressors | HVAC Refrigeration. Hello, I have a question about crankcase heaters and compressors. I am aware that they keep the refrigerant from saturating in the compressor when not running. However, if the refrigerant is R-22, it becomes saturated at approximately 40 degrees. We know the a/c is only operating at warm ambient temperatures. When it is off for the evening hours & the ambient temps stay above 40 degrees, why would one need to have a crankcase heater? Why do we need it on during this temperature range, or are crankcase heaters designed to be activated only during the colder months? Also, if one installs unregulated crankcase heaters (always operating), can this be a negative factor for the compressor life? (more…)