Air Handler Water Coil Freeze Stat | Freezing Protection Control No ratings yet.

Air Handler Water Coil Freeze Stat - Freezing Protection ControlAir Handler Water Coil Freeze Stat

Air Handler Water Coil Freeze Stat – The HVAC Air Handler Freeze Stat is a low temperature limit control and it is used mainly in commercial systems in the duct work on economizers or in air handlers just before any coil especially water coils. It is a safety and protection control to prevent extremely cold air from reaching the hot water or chilled water coils inside the air handler where the air enters from the economizer. Under ideal control set up if the freeze stat trips the economizer dampers close and the blower fan stops. This prevents coils from freezing. A frozen coil can bust open and will need to be replaced if it freezes thus the purpose of the freeze stat in HVAC air handler applications which utilize economizers for free cooling.

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Air Management in Hydronic Piping Loops No ratings yet.

Air Management in Hot and Chilled Water Piping LoopsAir Management in Hydronic Piping Loops

This is a secondary chilled water pump in a large pump room designated for pumps and piping in a data center. After a few minor tweaks and corrections these pumps all operated flawlessly. There was very little issues with the secondary pump start-ups unlike the primary pumps where cavitation was encountered on the primary chilled water pumps and the condenser water pumps for the chiller. The diagnosis for the cavitation of the primary pumps and the condenser water pumps was that the loops were not properly purged and this caused those pumps to cavitate. The secondary pumps, pictured here, did not have that problem giving kudos to the team that purged the loops on this side of the chilled water system.

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All About Hot Water Heaters | HVAC and Plumbing No ratings yet.

All About Hot Water Heaters | Water Heaters with Tanks and Tankless Water Heaters

Tankless Water Heaters
Tankless Water Heater

I have been transformed into a believer of tankless water heater systems. Anyone who has read the About Us page at High Performance HVAC along with my friends and family and some fans of the site know that I moved to Ukraine about a year ago for professional reasons. When I first arrived in Ukraine it took a while for me to adapt to the culture, language, services, and way they do things here. Power failures, water outages, and occasionally the natural gas outages are quite frequent here although it is tolerable and a minor inconvenience. Many of the outages occur at night when many people are sleeping but occasionally during the day when you need it. I must include that this has been a big adventure and I have learned much and to tell you if you are living in the States or Western Europe you have it good but that doesn’t mean Ukraine is bad it just means they are little behind and hopefully will quickly catch up. I have not seen a standard water heater here like the common water heaters with tanks in the States. All the systems I have seen here are tankless including the water heaters in the apartment I rented and now in the house where I live. I am sure there are tank-type water heaters here like in the States but I have not seen them yet.

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Water Tower Pumps and Controls | Pumping Systems No ratings yet.

Water Tower Pumps and ControlsWater Tower Pumps and Controls | Pumping Systems

Water Tower Pumps and Controls | Pumping Systems – Water towers maintain a ready limited supply of water for communities in the event the water main goes down. Many towers are used for emergency situations for the fire department to have water for fighting fires and for water fire suppression systems to have a supply of water for the emergency if it should arise.

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Domestic Hot Water Mixing Valve and Domestic Storage Tank No ratings yet.

Domestic Hot Water Mixing Valve and Domestic Storage TankDomestic Hot Water Mixing Valve and Domestic Storage Tank

Domestic Hot Water Mixing Valve and Domestic Storage Tank – This domestic hot water mixing valve offers a way to temper the hot water coming from a hot water loop and boiler. It is very important to maintain the appropriate and desirable temperatures of water used for domestic water use. First you want to maintain a safe temperature so people are scolded by extremely hot water temperatures. Boiler loops generally work on a temperature of 180 degrees Fahrenheit and this temperature is too hot for human contact without scolding or seriously burning the skin. A mixing valve is used in the loop to maintain a safe temperature for human comfort. The hot water is mixed with cold water at the mixing valve and the result is the temperature dialed into the mixing control valve which has a range of 120 degrees to 140 degrees if used for domestic hot water applications. Other mixing valves can be purchased that will give a whole range of temperatures including mixing valves that can be controlled by PLCs or DDC to maintain specific temperature ranges for whatever the desired temperature is for the application.

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Hot Water Boiler Economizer PreHeater | Energy Efficiency No ratings yet.

Hot Water Boiler Economizer PreHeaterHot Water Boiler Economizer PreHeater | Energy Efficiency

This is a hot water economizer and is a big preheater for domestic hot water use. This boiler plant serves a large community for heating and domestic hot water use. Domestic hot water is used for showers, washing dishes, laundry, ect, ect, ect…. The cold water supply from the city is routed through the economizer to be pre-heated before it goes through a heat exchanger and then the hot water storage tank. This system saves money because it uses the exhaust gases from the boiler to pre-heat the city water supply which is normally 50 degrees Fahrenheit. The exhaust gases from the boiler would otherwise be vented to the atmosphere and would be considered wasted heat.

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Furnace Water Leak Possible Condensate Problem No ratings yet.

Furnace Water Leak Possible Condensate Problem

Richard,

My furnace is leaking water and it is summer time so I am not using it for heat except for the blower fan which is hooked up for the air conditioner and the heat. I know the pipes from the outside units run into a box on top of the furnace so I think that is a part of the air conditioner. What can I do to fix the problem if you know what the problem is by my explanation here? Dan

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HVAC Definitions Terms & Acronyms | Heating Cooling No ratings yet.

HVAC Definitions Terms & Acronyms

This is a comprehensive list of HVAC Acronyms and HVAC Terms. High Performance HVAC is certain there are more terms and acronyms. If you know of something we missed please email us. Thanks!

HVAC Definitions Terms & Acronyms - VSD or Variable Speed Drives
VSD or Variable Speed Drives

AC – Air Conditioning or Alternating Current

ACCA – Air Conditioning Contractors Associations

AFUE – Annual Fuel Utilization Efficiency

AHU – Air Handling Unit

AI – Analog Input

AMCA – Air Movement and Control Association

AO – Analog Output

AQS – Air Quality Systems

ASHRAE – American Society of Heating, Refrigerating, and Air Conditioning Engineers

AV – Automatic Air Vent

AWG – American Wire Gage

B – Boiler

BACnet – Computer communication protocol for building automation systems and control networks

BAS – Building Automation System

BI – Binary Input

BMS – Building Management System

BO – Binary Output

BP – Backflow Preventer

BTU – British Thermal Unit

BTUh – Brtish Thermal Units per Hour

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Grounding and Bonding Electrical Systems | NEC Code No ratings yet.

Grounding and Bonding Electrical Systems and the NEC

Grounding and Bonding Electrical Systems

National Electrical Code Article 250 is all about grounding and bonding as represented in this photo where electrical systems are grounded and bonded to the buildings steel structure. There are many different rules in the NEC (National Electrical Code) pertaining to grounding and bonding because grounding and bonding are important for safety reasons. Electricity will take the path of least resistance so if there is a short in the system the grounding system will be the path for the electricity instead of the motor or load that experiences the short. The NEC defines specific sizes for grounding wires based on the size of the wire serving the building plus each different load has specific grounding and bonding requirements. For example, a rooftop air handler may have several loads including a supply fan and a return fan. Each fan motor will specific needs for grounding wire size in relation to the size of the wire supplying electricity to the motor. In a residential setting it is important to follow the code and ensure your receptacles have a good ground for the protection

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HVAC Piping Valves | Heating and Cooling Hydronics No ratings yet.

HVAC Piping Valves | Heating and Cooling Hydronics - Automatic Flow Valve
Automatic Flow Valve

HVAC Piping Valves | Heating and Cooling Hydronics

Triple Duty Valves are three valves in one as the name implies. Triple Duty Valves act as a check valve, balancing valve, and a shut-off valve all in one valve. From the smallest hydronic loops to the largest hydronic loops triple duty valves are very a popular selection for engineers when designing hydronic loops for chilled water and hot water applications. The triple duty valve consists of a threaded stem attached to a disc. The disc has a spring that will allow the disc to open when flow is induced throughout the loop. The disc will only allow flow in one direction and shuts whenever the flow is reverse of the normal flow. The threaded stem can be adjusted to allow a specified amount of flow through the valve and is usually set by a testing and balancing technician. The stem can also be turned all the way down to shut off flow in the system. Those three options in one valve give the triple duty valve its name. Triple duty valves are usually constructed of heavy duty cast iron and installed in the hydronic near the pumps.

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Hot Water Boiler Piping Zone Valves No ratings yet.

Hot Water Boiler Piping Zone Valves

Hot Water Boiler Piping Zone Valves

Boiler piping zone valves are used for zoning hot water systems where multiple zones are needed. Hot water system zoning can also reduce energy cost because hot water heat zones which are not needed can be shut down thereby reducing boiler run time to provide hot water heat for those specific zones. Zoning a hot water boiler system can be done by using these zone valves and separate thermostats for each zone. The boiler piping loop is separated using zone valves on a manifold type system with each zone originating at the manifold. The manifold is piped directly to the boiler.

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Chilled Water Storage Tank | Critical Facilities No ratings yet.

Chilled Water Storage TankChilled Water Storage Tank | Critical Facilities

Data centers use redundant systems for back-ups in case of an emergency. An HVAC chilled water storage tank adds an extra layer of redundancy to the process so if the chiller plants crash the chilled water storage tank or tanks will provide a small cushion of time to allow the operating engineers time to straighten things out or in a worse case scenario allow time for the servers in the data center to be transferred to another data center and shut down. Typically storage tanks will only allow for about 30 minutes to an hour before the data center floor reaches critical level and the servers need to be shut down. There are other applications for using chilled water storage tanks currently in use that save energy by storing chilled water in large thermal tanks for use during peak load times. During the day the stored chilled water is used instead of chillers. This reduces peak load saving money by utilizing the cheaper KW’s the utility company provides at night.

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How Cooling Towers Work | Commercial HVAC No ratings yet.

How Cooling Towers Work - Large Cooling Towers Serving a Data Center
Large Cooling Towers Serving a Data Center and Commercial Building

How Cooling Towers Work

How Cooling Towers Work – Cooling towers use evaporation cooling to cool condenser water from a chiller. Water is pumped to the top of the cooling tower where the water flows down some flow plates to the cooling tower basin. As the water is flowing down the flow plates air is pulled through the plates and over the water where it releases heat through evaporation. After the water has released the heat it is then pumped back through piping to a chiller barrel where it absorbs more heat and then returns to the cooling tower. Because of evaporation the cooling tower system is equipped with a float that controls the level of water in the basin to prevent the water from evaporating away and giving the system a shot of fresh water called make-up water. When the float drops below a predetermined level a valve is opened introducing make-up water into the cooling tower system. The make-up water is generally supplied from the city water supply or even a well. High efficiency cooling towers have variable frequency drives that can be controlled by a reset schedule based on outside ambient air temperature. This feature saves energy by allowing the fan to run at lower speeds based on lower temperatures outside. HVAC Cooling towers also require water treatment chemicals and regular maintenance for cleaning, belt and motor maintenance. Some cooling towers use filters to filter unwanted particles from the water.

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Chilled Water System Basics | HVAC Cooling No ratings yet.

Chilled Water System Basics

Chilled Water System Basics – Chilled water systems work much the same way as direct expansion systems work except they used chilled water in the coil rather than refrigerant (Technically speaking, water can be classified as a refrigerant). Chilled Water systems can be rather complex and many chilled water systems are found in commercial and industrial applications. Chilled Water System BasicsThere are some chilled water systems used in residential applications. However, chilled water systems in residential HVAC systems are extremely rare. A typical chiller uses the process of refrigeration to chill water in a chiller barrel. This water is pumped through chilled water piping throughout the building where it will pass through a coil. Air is passed over this coil and the heat exchange process takes place. The heat in the air is absorbed into the coils and then into the water. The water is pumped back to the chiller to have the heat removed and make the trip back through the building and the coils all over again.

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Aquastat Temperature Control | Boiler Components No ratings yet.

Aquastat Temperature Control | Boiler Components

Boiler Components: Aquastat Temperature ControlThe boiler aquastat controls the temperature of the water inside the boiler jacket. The boiler aquastat is a device to a boiler like a thermostat is to an air conditioner, heat pump, or gas/oil furnace. The boiler aquastat controls the temperature inside the boiler just as the thermostat controls the temperature for an air conditioner or heat pump. The boiler aquastat will turn the burners on and off and also controls the circulator pump on a hot water boiler system.

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HVAC Near Boiler Piping Components No ratings yet.

HVAC Near Boiler Piping Components

HVAC Near Boiler Piping ComponentsHVAC Near Boiler Piping Components – HVAC near boiler piping is very important to a good hot boiler loop circulation of the water. Hot water loop piping is key to maintaining good water flow throughout the system. The placement of valves, the circulator pump, and other loop controls are generally installed near the boiler. In the photo one can see the circulator pump, the expansion tank, the flue that exhausts the gases from the combustion process, an automatic air vent just to the right of the hot water loop circulator pump, a PRV or pressure reducing valve where the boiler make-up water comes into the boiler, and some unidentifiable controls. These loop components make up the near boiler piping which is very important to a good installation. If the near boiler piping is not installed properly several problems can occur that will cause issues with the heat and efficiency of the heating system as a whole.

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Hot Water Heaters No ratings yet.

Hot Water HeatersDomestic hot water heaters make our lives much more comfortable than ever before. Hot water heaters give us hot water for washing our hands, showering, washing dishes and other uses that would otherwise be uncomfortable without a hot water heater. When considering hot water heaters beyond the cost of the water things to consider are the size of the hot water heater and the type of fuel it will use to heat the water. Efficiency plays a key role in the decision also and while the more efficient models are more costly to purchase paying the higher cost now will save a lot of money down the road in energy savings. Additionally, with all the tax incentives and utility incentives buying the more efficiency model may cost less than the less efficient water heaters. Before looking for a water heater it might be a good idea to check with your local utilities to find out what kind of incentives are available for buying higher efficient water heaters. After checking with the local utilities then you can go out looking for the best water heater to suit you and the purpose you need the water heater for. Tankless water heaters can also be a consideration although these should be sized by a professional so you don’t get too small of a tankless water heater (not enough hot water) or too large of a tankless water heater (inefficient).

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Water Dripping from Air Conditioner | Condensation Drain Pipe No ratings yet.

Water Dripping from Air Conditioner

Condensation Drain Question:

Condensation Drain Pipe - Water Dripping from Air ConditionerWe have 2 air conditioning units in our house and 2 pipes protrude from the roof. One of the pipes is dripping water. We were told to look for a blockage and to empty the pans. I don’t see where to check for a blockage. Any suggestions?

The air conditioning units we have are: Bryant models 373LAV, 376CAV Downflow/Horizontal and 383KAV, 395CAV Upflow Gas Furnace.

Water Dripping from Air Conditioner  | Condensation Pipe Drain Answer

Thanks for visiting High Performance HVAC and asking a good question. I see you have two zones so actually you should have more than two drains. Possibly 3 or 4 drains depending on where the units are located. Typically air handling units installed in the attic or closet spaces upstairs will have two condensation drain pipes for condensation. One is the primary condensation drain pipe where the water should continuously drain the condensation during the cooling season and in the winter heating season if you have a high efficiency condensing furnace. In the summer it is possible these drains could get clogged up. Normally what clogs these condensation drain pipes is algae and crud growing in the pipe. It will usually block or clog the primary condensation drain causing the water to back up in the unit. The water eventually finds its way to the secondary or emergency drain pan which should also have a condensation drain pipe attached to it that drains out the water when the primary condensation drain pipe gets clogged.

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Automatic Air Vents | HVAC Hydronics No ratings yet.

Automatic Air Vents

Automatic Air VentsThe automatic air vent is found in the piping system of water loops. If air is introduced into the water loop system it eventually finds its way to the automatic air vent where it is vented. The automatic air vents are located throughout the system. Air bleeders may also be found throughout any hydronic loop system. A hydronic loop is a water loop. These water loops can be for hot water or chilled water. Any hydronic loop needs an air management system or automatic air bleeder system to keep the air out of the system otherwise the air will be up in the system and air will block or prevent the flow of water throughout the loop. Water naturally has air in it. Automatic air vents help the water loop by:

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Watts Backflow Preventers | Water Safety No ratings yet.

Watts Backflow Preventers Back Flow Preventors

Watts Backflow Preventers | Water Safety

Backflow preventers are necessary on water loops where the water is used in a hydronic loop that heats or cools the water through a boiler or chiller system. This Watts backflow preventer is installed on a large boiler system that heat thousands of gallons of water. The hydronic loops are designed to be hermetic. However there are always some loss of water somewhere in the system. For safety purposes to prevent the boiler from losing all of its water, a make-up water loop is connected to the loop. The make-up water feed needs backflow preventers installed in the pipe to prevent any of the boiler or chilled water from getting back to domestic water feed for the make-up water.

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