Air Conditioner Components | HVAC Cooling 5/5 (1)

Air Conditioner Components

Air Conditioner Components | HVAC CoolingThere are big differences between heat pumps and air conditioners. While the air conditioner provides cooling the heat pump will provide heating and cooling so the components inside the air conditioner differ from the components inside the heat pump system. I constantly get emails from people asking if they can convert their air conditioner to a heat pump and of course they can but it is not recommended. I have even devoted an article to it for those who are considering converting their air conditioner to a heat pump.  After all, if you sit a heat pump next to a condenser it would be impossible to tell the difference from the air conditioner condenser to the heat pump condenser unless you looked inside the unit and was able to identify the different components from a heat pump to an air conditioner.  Here are the basic components of an air conditioner that make the air conditioner cool your home or business.

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Evaporator Coil for Heat Pumps & Air Conditioners | HVAC Refrigeration 5/5 (1)

Evaporator Coil for Heat Pumps & Air Conditioners

Old Evaporator Coil in a Rooftop Air ConditionerEvaporator Coil for Heat Pumps & Air Conditioners – the evaporator is responsible for absorbing heat into the coils and the refrigerant. The evaporator is an essential component of vapor compression refrigeration. This is usually done as result of passing air or water over the evaporator coil where a heat exchange process takes place. Heat leaves the air or water (whatever medium is used) and is absorbed into the coil and the liquid refrigerant. As more and more heat is absorbed by the evaporator coil and the refrigerant again changes state from a liquid to a refrigerant vapor. By the time the refrigerant leaves the evaporator coil the refrigerant should be all vapor and ready to be received again by the refrigeration compressor.

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Fixing a Refrigerant Leak | Air Conditioner & Heat Pump Diagnosis & Repair 5/5 (1)

Fixing a Refrigerant Leak

Fixing a Refrigerant Leak – You had the new air conditioner or heat pump system installed some years ago and suddenly it stopped heating or cooling properly so you call the HVAC contractor to check it out. The HVAC technician arrives and spends about thirty minutes HVAC troubleshooting and then he comes to you with the news. The unit needs a charge of refrigerant. It is low on refrigerant (R-22) or R-410A. You ask the HVAC technician if it is normal for this to occur and he informs that, no, it is not normal for the HVAC system to lose refrigerant that you have a refrigerant leak.

So you advance to the next question and ask, “can you find and fix the refrigerant leak”. The HVAC technician says yes he can. Here are the options for you and depending on which option you choose will depend on the cost.

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Variable Speed ECM Blower Motors | HVAC Heating & Cooling Systems 5/5 (1)

ECM Variable Speed Blowers

Variable Speed ECM Blower Motors
An ECM Variable Speed Blower Motor in a squirrel cage blower

Variable Speed ECM Blower Motors – Variable speed blower motors have become increasingly popular in residential air conditioning and heating systems and for good reason; these motors increase efficiency of the systems and offer a whole range of other benefits that help the system and the consumer.

We have many other related articles. Please use the search feature to the right to help you find other related articles.

Variable Speed ECM Blower Motors

Variable Speed Blower Motors first offer a higher efficiency for air conditioning systems based on the manufacturers set up of the control with the ECM Variable Speed Motor. Each manufacturer calls it a different thing such as Trane calling it the Comfort R  and Carrier calling it Infinity Control. Despite what the manufacturer calls it helps efficiency with air conditioning by starting the blower slowly and letting it run at a 50% speed for the first few minutes (up to 7 minutes) to remove more humidity. This increases comfort and efficiency by removing more moisture from the air. The lower the humidity in the cooler you will feel so the variable speed blower with this type of control will enhance comfort.

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Running New Thermostat Wire – New Installation No ratings yet.

Running New Thermostat Wire Running New Thermostat Wire – It is possible that you may have to run a new thermostat wire from the air handler or furnace to the location where the existing thermostat is located. Running new thermostat wire can challenging even for professionals. If you must the follow will hopefully help you in … Read more…

2011 Proposed Increase in SEER – EER – AFUE – HSPF 5/5 (1)

This article is archived for future records. Please refer to DOE website for reference on current energy efficiency guidelines.

 

10 SEER units cannot be purchased in the US any longer. The new standard as mandated by the Department of Energy as of January 2006 is 13 SEER. This 30 percent increase in efficiency from 10 SEER requires a change out of the inside coil. In 2011 the Senate is proposing a new SEER and AFUE standard that will be based on where you reside in the USA. The country will be split up into three regions. Northern, Southern, and the Southwestern regions with each region having different efficiency standards. The proposed efficiency standards for each region are as follows:

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Duct Work and High Ceilings | HVAC Duct Work Systems No ratings yet.

Duct Work and High Ceilings

Duct Work and High Ceilings | HVAC Duct Work Systems

Duct Work and High Ceilings – I did not see any reference to my question and would appreciate a response as soon as possible, as due to medical situation, have to make a decision soon. We own an OLD house with 13′ ceilings in a large part of the home and 11″ ceilings in the LV/DR and BR. We are oscillating on where to place the ducts….Floor or ceiling. It appears to be counterproductive to me to put the duct work in the ceiling since it will have so far to go. We are looking for the most cost effective, not upfront cost but operating cost, solution. In addition, we are considering DF heat pumps. The house will need 2 or 3 to be zoned correctly. Please let me know about the duct placement and thank you for your help?

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Variable Air Volume Box with Hot Water Reheat | Commercial HVAC No ratings yet.

Variable Air Volume Box with Hot Water Reheat Variable Air Volume Box with Hot Water Reheat – The variable air volume box or VAV box is a commercial solution to adding multiple zones to large buildings. VAV boxes offer zoning solutions so that separate zoning demands or temperature selections can be maintained in different areas of … Read more…

Air Handler Equipment DDC Controllers | HVAC Control 5/5 (1)

Air Handler Equipment DDC Controllers

Air Handler Equipment DDC Controllers | HVAC Control

Air Handler Equipment DDC Controllers – These controllers will control an air handler once the wiring is completed. The panel is freshly mounted and waiting for the technician to run the piping and pull the wire from the control points. Other points, such as outside air, temperature sensors in piping or duct work, flow meters, actuators, or other control points can be terminated to these controllers and the data collected from those input points can be networked over the entire building automation system through the communication trunks. Included in this panel are: a terminal strip connection point for line voltage and control voltage, a transformer to step-down line voltage to the required control voltage of 24 volts which powers the controllers and a surge arrestor which is a requirement on many government jobs.

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How DDC Status Works – Methods and Types | HVAC Control 5/5 (1)

How DDC Status Works – DDC and Status – Is the Device On or Off

How DDC Status Works? DDC Status Methods and Types
This is a current switch sometimes referred to as a CT switch. This switch has an adjustable range from 1 to 200 Amperes. This switch also has a trip setting so it will trip if an adjusted set amount of amperes is exceeded.

The basics of DDC include learning about the status of a fan or a compressor or pump. How does a DDC controller read the status of the device it is monitoring? There are several ways to prove a device is running and some pros and cons of each type of device used to monitor on or off status. This is a basic DDC guide or reference to help a person understand the basics of DDC status and how it works. When one learns how DDC status works they can improve their troubleshooting skills. Too many maintenance technicians and others including HVAC technicians don’t understand DDC systems or building automation systems and are therefore crippled when it comes to troubleshooting DDC systems. High Performance HVAC hopes to change that and help HVAC techs and HVAC maintenance staff learn the basics of DDC systems including how DDC status works. Once someone understands the basics about DDC a light will turn on and they will see that DDC is not really rocket science.

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HVAC Control and Direct Digital Controls 2 | DDC & BAS 5/5 (1)

HVAC Control and Direct Digital Controls – The (Field) Technical Aspects of Direct Digital Control

A HVAC technician who knows nothing about HVAC control systems would wonder how these hvac control systems work. To understand hvac controls, one must understand basic electricity and circuits. Starting with a large commercial VAV air handling unit with three stages of DX cooling and add all the necessary hvac ddc control points. We have variable frequency drives (VFD’s) on the return and supply blower fans. There is a mixed air damper which closes off the return and opens up to outside air for economizing and CO2 control. Static pressure control will be achieved with a duct pressure transducer and the HVAC control program through the frequency drives and blower motors. Direct Digital Control needs to monitor supply air temperature, mixed air temperature, and return air temperature along with outside air and outside humidity. We will also monitor the duct smoke detectors and a freezestat for safety reasons. This is the set-up and we need to make it work. We need to get a point count and set-up our inputs and outputs.

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The NEC and HVAC Chapter Two 5/5 (1)

The National Electrical Code (NEC) and HVAC: The Basics

The NEC and HVAC Chapter Two

The NEC and HVAC Chapter Two – Chapter Two of the National Electrical Code (NEC) covers Wiring and Protection and starts at Branch Circuits, Feeder circuits, GFCI requirements and protection,. An HVAC installer may want to pay attention to branch circuit requirements. Article 220 in Chapter two of the NEC includes calculations for branch and feeder circuits including service calculations. (Table 220.3)

  • Specific branch circuit requirements for HVAC can also be found in Chapter 4 Article 440 – Air Conditioning and Refrigerating Equipment Branch Circuit Conductor Sizing
  • Article 424 – Fixed Electric Space Heating Equipment Branch Sizing
  • An entire chapter on motors including feeder circuits for motors

Chapter Two of the NEC also covers basic lighting which by code is done by Volt-Amperes per square foot. (Table 220.12)

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Find Tonnage on AHU | HVAC Equipment Nomenclature 5/5 (1)

Find Tonnage on AHU | Equipment Nomenclature

How do I find out the tonnage on a AHU? The label/tag has faded all I have on file is the model number and the serial number, make.

Question Posted By Francisco the Building Engineer on May 3, 2011

Refer to the manufacturers website for their HVAC nomenclature of model number and serial numbers and how those numbers correspond to the tonnage and other technical data. Or you can call your local dealer for the manufacturer and they will tell you.

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Building Automation Systems | HVAC Control 5/5 (1)

Building Automation Systems | HVAC Control

What you will learn from this article:
1) the efficiency and conveniences Building Automation Systems add to a building
2) how Building Automation enhances energy savings and troubleshooting problems
3) how allowing controllers to communicate with each other enhances HVAC and electrical systems
4) many of the benefits of building automation systems
5) Resource and Related Links to help you learn more

Building Automation Systems – HVAC ControlMany people wonder what Building Automation Systems (BAS) do. BAS is mainly used in commercial HVAC control systems and energy management system applications. Building Automation itself is an energy management system which saves management companies and building owners by efficiently controlling air conditioning and heating comfort and process systems. BAS is where mechanical and electrical systems and equipment are joined with microprocessors that communicate with each other and possibly to a computer. This computer and controllers in the building automation system can be networked to the internet or serve as a stand alone system for the local peer to peer controller network only. Additionally, the BAS controllers themselves do not need a computer to process the control functions as the controllers have their own internal processors.

Related Link: Learn more about DDC control loops (opens in a new window)

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Preventive Maintenance Air Handlers | York AHU’s 5/5 (1)

 Preventive Maintenance Air Handlers | York AHU’s

York Air Handlers – Preventive Maintenance Air HandlersThese air handlers provide air conditioning for a zoned VAV system. The air handler is an integral part of an air conditioner system. The air handler contains a blower, air filters, some coils (DX or chilled water), hot water coils (not all air handlers have heating coils in them), and some controls.

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Thermostat Wire Colors Code | HVAC Control 4.67/5 (3)

What you will learn in this article:
1) What thermostat wire color is likely to go to which terminal on the thermostat
2) The function of each wire terminal on the average thermostat highlighting some of the differences in those functions from manufacturer to manufacturer

Sometimes the thermostat is not the problem. Please check this article for a checklist of things to check before calling a heating and cooling repair service.

Thermostat Wire Colors Code | HVAC Control

Thermostat Wire Colors CodeThermostat Wire Colors Code – Always follow the thermostat manufacturers instructions whenever changing the thermostat. Always turn the power off at the air handler and the condenser and make sure there is no voltage at the transformer before proceeding. The thermostat wire colors below are the most likely colors used for most installations however your thermostat wire colors may be different than what is indicated here. There is no official standard for thermostat wire colors. Thermostat wiring colors are not standardized but these are the most wiring methods used based on my years of experience in the HVAC field where I successfully wired a lot of thermostats.
Honeywell Thermostats Available Here

For instructions on how to wire a thermostat please see our how to wire a thermostat page.

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Chilled Water Pipe Vibration Isolators | HVAC Piping No ratings yet.

Chilled Water Pipe Vibration IsolatorsChilled Water Pipe Vibration Isolators

Chilled Water Pipe Vibration Isolators – Vibration isolators protect the chilled water piping from receiving vibrations transmitted through the piping when the chillers are running. The vibrations can create problems not only for the chilled water piping but also for the buildings structure. The vibration isolators reduce or eliminate the vibrations that can be transmitted by the chillers. Other equipment normally specified with vibration isolators includes air handlers, pumps, condensing units, generators and most types of equipment with motors. Not only are vibration isolators required in the piping but vibration elimination springs or spring isolators are required are required on chillers, pumps, air handlers, and the other types of equipment named above which can produce vibrations when running. Vibration isolators are usually rated according to the static deflection the vibration isolator provides for the equipment. HVAC piping whether it is for hot water or chilled water usually is also specified with springs in the pipe hangers to avoid further issues that can be caused by vibration. Depending on the location vibration isolators will also be rated for seismic activity with further specifications calling for seismic restraints on the equipment and associated piping.

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Hot Water Unit Heater Protecting a Mechanical Room No ratings yet.

Hot Water Unit Heater Protecting a Mechanical RoomHot Water Unit Heater Protecting a Mechanical Room

Unit heaters are used in various places to protect equipment and provide comfort to occupants. This hot water unit heater provides protection for a mechanical room where there is a large air handler and other associated equipment in the mechanical room. This system is controlled by DDC. A thermostat on the wall detects the temperature of the mechanical room. The DDC system will maintain a temperature set point by energizing the hot water unit heater fan and modulating the hot water valve open on the hot water piping. The actuator and hot water valve can be seen in this photo on the right lower half of the system. The valve is a two position valve so it is either open or closed with no modulating the valve on the unit heater. Other unit heaters for heating mechanical rooms or providing comfort include electric units heater when hot water is unavailable, gas fired unit heaters when gas (either propane or natural gas) is available, and infrared heaters typically found in large garages or warehouses for basic comfort of workers in those spaces. There are also steam unit heaters that utilize steam and a steam coil for heating spaces where steam is available. Most unit heaters are forced air unit

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Building Automation Systems or Direct Digital Controls Learning | HVAC 5/5 (1)

Building Automation Systems or Direct Digital Controls Learning
Siemens Apogee DDC Controller

Building Automation Systems or Direct Digital Controls Learning – HVAC Building Automation Systems (BAS) or Direct Digital Controls (DDC) is pretty much one in the same. Basically described BAS and DDC is combining air conditioning, heating, ventilation, lighting, electrical loads, security systems, and life and safety systems to a computer and complex algorithms for better control over the systems and to offer higher efficiency levels that could not otherwise be achieved without computer control. The are many different opportunities inside the BAS or DDC field but you have to start somewhere. Commercial HVAC Technicians and Electricians are commonly hired into positions as DDC or BAS technicians and BAS and DDC installers. Where do you begin if you want to get into the field of HVAC BAS and DDC

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York Affinity Versus Carrier Infinity Air Conditioners No ratings yet.

York Affinity Versus Carrier Infinity Air Conditioners

Every manufacturer has there own parts system and sometimes these parts are readily available aftermarket and sometimes the parts are proprietary and can only be purchased through manufacturer of that equipment. Carrier is one of the HVAC manufacturers that has proprietary parts and sometimes you will pay a premium for those parts.

The manufacturer can hold the customer hostage especially when it comes to repairing the unit. Of course York is one of the big HVAC manufacturers and they too have proprietary parts however the parts are usually more reasonable for purchase as far as cost is concerned so people would lean towards purchasing a York simply because the replacement parts are are not sold at a premium where with SOME Carrier parts are sold at a premium and are not easily replaceable except through a Carrier dealer.

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