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Power Factor

Electrical

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May 19, 2022

How a Power Factor Works.

We’ll learn what a power factor is, and how to correct a bad power factor. How to calculate the power factor. What causes a poor power factor, and what can be used to make the power factor better.

To watch the FREE YouTube version of this presentation, scroll to the bottom.

First, we’ll introduce the characters that are involved in calculating the Power Factor. There are three terms in addition to Power Factor that you need to know.

Active Power – Reactive Power – Apparent Power

#1 We have the “Active Power” in (kw) which is the real electrical power required by motors, heaters, computers, ballast-based lights, transformers, etc. This active power is transformed into heat, light and mechanical energy. This is the work we want done in our buildings. Alias, Real power, True Power.

#2 We have “Reactive Power” in (kvar) which supplies the equipment in the building that uses magnetic circuits, like motors and transformers. This reactive power is what causes all the problems if not controlled, which will explain shortly.

#3 We have “Apparent Power” in (kVA) which is a result of the mix of the first two types of power. The larger the Reactive Power, the greater the Apparent Power. Will explain all these terms in greater detail. Alias, Total Power

#4 Is the “Power Factor” which is derived by dividing the “Active Power” into the “Apparent Power”. Kw/kVA

What is a Power Factor?

A power factor represents how efficiently a building uses the electrical power that the utility company provides. A power factor of 1 is the best factor, which represents 100% effective use of the power delivered. This is unlikely as there are factors that affect the quality of the power within a facility or building, such as induction motors.

Think of a power factor as a Grade given to a building by the utility company, like your teacher would give you a grade for a math or English class. The grade indicates how well the building uses the electrical power that the utility company provides, and the scale is 0 to 1, with 1 being the best factor or grade. You can think of it also as 0% to 100%, with 1 equal to 100%.

The possible punishment for a building that gets a bad grade or poor power factor is an extra fee charged on their utility bill and loss of additional kw capacity. This fee can add up to a large amount of money for a customer with a lot of induction load.

Power factors that are below 1.0 causes the utility company to generate more power to meet the demand. This causes an increase in the generation and transmission cost, which is passed on to the customer in the form of a reactive power (kvarh) fee or a percentage surcharge on their utility bill.

We can represent these three terms using a power triangle and demonstrate how reactive power effects apparent power.

You can see using this power triangle that as the Reactive Power gets larger it requires more Apparent Power (kva) from the utility, but the Active/True Power remains the same. The true power (kw) is what the building needs to run its motors, and the reactive power is just making things more expensive for the utility company and the customer. The reactive power needs to be reduced or controlled as much as possible.

Power Factor (PF) = KW / KVA

The power factor is the True/Active power (kw) that the building requires to power its machinery divided by what the utility company provides in Apparent Power (kva). The power factor tells us how efficient the building is in using the power.

This means that the lower the reactive power the less the customer pays for apparent power (kva) to run their load (kw). Remember the utility must deliver the required apparent power (kva) even though the customer only needs the True/Active power (kw).

As an example, if a building required 1,000 KW of power and had a power factor of 100%, then it would only require 1,000 KVA of generating and distribution network capacity. If the power factor dropped to 80%, however, 1,250 KVA of capacity would be needed. The lower power factor has an adverse effect on generating and distribution capacity.

PF Example. What happens when your PF worsens. — Power Factor Example

The lower the power factor the greater the burden on generation, distribution, and networks, due to excess KVA.

What Causes Reactive Power

Reactive power is caused by something that is found in just about every building, and that’s induction motors. Induction motors are required in every industry to perform work, so we can’t get rid of them, so there will always be some reactive power.

AC Induction Motors

The cause of all the problems begins with the AC (Alternating Current) motors. Induction motors use magnets that cause power quality issues. We need magnets to get motors started. If you have a lot of motors in a facility, like industrial buildings, then you’ll have a poor power factor unless something is done to correct it.

How to Correct Poor Power Factors

How does a building owner go about correcting their power factor to reduce wasted energy and cost, while increasing distribution and transformer efficiencies?

By adding capacitors to the system where induction motors are the main cause of the problem, the building can improve its power factor and network efficiency. The effect of Capacitance is opposite that of inductance.

Capacitors can be in various places within the electrical system to improve the power factor.

As this single line electrical diagram shows, power factor correction equipment can be located centrally (CPC) to handle the complete building, or regionally (RPC) within the building, or at individual Local (LPC) loads, such as motors.

Power Factor Correction using Capacitors. Location varies as shown above.

Locating the capacitor at the motor corrects any interference coming from the motor. If you have a lot of motors, then you might consider locating the capacitor at the service entrance switch gear to avoid having capacitors all over the facility.

Wherever the capacitor is located it will improve the power factor between that point and the power source. Remember that this means the power factor between the capacitor and the load or motor will remain unchanged.

Capacitance causes voltage to lead current, while inductance causes current to lead voltage.

Why Correct the Power Factor?

As we previously showed, the building can free up additional electrical capacity (kw), while reducing system losses in cables and transformers. These system losses heat up the electrical power lines which causes a loss in their capacity, as the reactive power contributes to those loses and thermal overloading. Improving the power factor reduces power loses, saves energy, and lowers the buildings overall CO2 emissions.

A poor factor (PF) will cause the line current to increase, causing losses in the distribution system and transformers. Even though the building uses the same Real Power, the lower factor (PF) cost the utility company more to generate and distribute.

Improved Power Factor and Increased Power (kw) Capacity

Having higher current requirements due to lots of Reactive Power could result in the overload of transformers, less available active power (kw), increased temperatures of electrical supply cables, higher voltage drops, increased energy consumption and cost. The building would require larger wiring, transformers, switches, etc., because of higher current and KVA.

Therefore, it’s important to correct Reactive Power by adding capacitors. The capacitors will produce reactive energy in opposition to the energy absorbed by induction loads such as those produced by magnets in motors. This is how Power Factor Correction is achieved. Basically, the capacitor is providing the reactive power required by the motor, so the utility doesn’t have to.

This will result in lower apparent power, improved power factor, increased capacity available, reduced power losses, and reduced cost to the building.

Increased Available Power (kw)

By increasing the power factor, you increase the available power (kw) for the facility. This is very useful if a building has reached its limit in the available power and needs to add additional power consuming devices.

Increased Power Capacity with Reduction in Reactive Power

Increasing the power factor (PF) by reducing reactive power (kvar) and maintaining the same apparent power (kva), a building can increase its (kw) usage capacity. Improving the factor free’s up additional capacity being wasted by reactive power. If you don’t choose to use the added capacity (kw), then your Apparent Power will be reduced along with the energy cost.

As the chart shows if a building has a power factor of 0.7 and increases it to 0.9 it increases the available power by 28%.

Savings on Electric Utility Bills

Utilities usually start charging a facility when their power factor drops below 0.90 to 0.95. The utility can charge based on the apparent power (kva) instead of the True/Active power (kw).

Buildings are charged for the circulation of Active Power over a period of time as indicated by kwh (kilowatt hours), while some utilities also charge for Reactive Energy over a period of time as indicated by kvarh (kilovolts-ampere-reactive hours). By improving the power factor, this charge will also be reduced or eliminated. The savings from the reduced charges can help pay for the added expense of making the improvements to the power factor.

Reduction in Cable Sizing

By improving the power factor, less current is required, which means smaller conductors. A factor of 0.5 could require cross-sectional cable sizing twice that of a power factor of 1.0. As the table shows the increase in cabling size due to a worsening factor.

Reduction in Voltage Drop

The voltage drop will be improved upstream of where the capacitors are installed and avoids overloading the utility network.

Sizing of Capacitors for Correcting Power Factor

To determine the size of a capacitor or the total kvar needed for a single load or entire power system we’ll need to determine the kw factor by gathering the following data: Actual Power (kw), existing and desired power factor.

Sizing Capacitors for PF Correction — Sizing Capacitors for Power Factor Correction

With this information you can use an online calculator or manufactures chart to discover the required KVAR. The KVAR rating of a capacitor shows how much reactive power the capacitor will supply.

The formula is KVAR = kW x kW Factor

How a Power Factor Works

How a Condensing Boiler Works

MEP Academy Instructor

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May 15, 2022

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How a Condensing Boiler Works. We’ll explain how condensing boilers or condensing heaters work and their residential and commercial applications. Why are condensing boilers more efficient than the standard non-condensing boilers? We’ll explain what you should think about before adding a condensing boiler to your home or commercial property.

To watch the FREE YouTube version of this presentation, scroll to the bottom.

Before we explain how a condensing boiler works, it’s best to understand how a conventional non-condensing boiler operates.

Checkout these Condensing Boilers here

How Standard Boilers Work

The conventional non-condensing boiler uses one heat exchanger to transfer heat between the burning fuel and the water. As the water enters the heat exchanger it absorbs heat from the combustion of fuel that has been ignited with a mixture of air.

The water enters cold, and leaves heated for use in heating spaces or domestic water purposes. The high temperature flue gas is exhausted out to the atmosphere through a vent. This is wasted heat and energy that you have paid for. If this boiler is 75% efficient, then basically you’ve exhaust 25% of your money out the flue. The condensing boiler makes use of this heated flue gas before its exhausted to the atmosphere.

How Condensing Boilers Work

How a Condensing Boiler Works by using two heat exchangers instead of one. This additional heat exchanger is used to capture the heat from the flue gases being exhausted. It’s called a condensing boiler becomes it removes latent heat (moisture) from the hot flue gas causing water to condense out of the flue exhaust air. This moisture collects at the bottom of the heat exchanger and must be drained to an approved drain receptor, much like you would with an air conditioners condensate drain. Since the heat exchanger is exposed to moisture it must be made of non-corrosive material, such as stainless steel.

Checkout these Condensing Boilers here

This condensate from the boiler must be treated before it is allowed into the drain system, because it’s considered acidic. This is accomplished by adding a little inline filter on the drain line. The filter may contain limestone which absorbs some of the acidic nature of the condensate, neutralizing it before it enters the drain.

The incoming cold water is preheated as it passes through the secondary heat exchanger before it enters the primary heat exchanger. This secondary heat exchanger is what increases the efficiency of the condensing boiler. The secondary heat exchanger gives the condensing boiler a second opportunity to absorb heat from the energy expended during combustion, by absorbing heat from the exiting flue gases. By capturing heat that would otherwise be wasted the condensing boiler achieves higher operating efficiencies.

These higher efficiencies are why condensing boiler are mandated in some jurisdictions, and why utilities often offer rebates. Check with your local utility company to see if rebates or incentives are available for changing a conventional boiler to a condensing boiler. Non-condensing or standard boilers have a range of efficiency from 75% to 84%, while condensing boilers can exceed 90% and all the way up to 98%. This will allow you to save on your annual fuel cost while also helping the environment.

Non-condensing Boiler vs Condensing Boiler

If you spend a dollar on fuel for your standard boiler at 75% efficiency, then you are throwing away 25% of your money through the heated exhaust gases. This is $0.25 cents for every dollar you spend. With a condensing boiler or heater that is 95% efficient, you are making your dollar more efficient as now only 5% is wasted in the exhausted flue gas. This means that for every dollar you spend, only $0.05 cents is wasted on flue gas exhaust.

Within the condensing boiler, the flue gas and water travel in opposite directions. The flue gas first enters the primary heat exchanger, while the water first enters the secondary heat exchanger.

Checkout these Condensing Boilers here

Flue Gas Material

Since a condensing boiler has much lower flue gas temperatures, most manufactures recommend the use of PVC or CPVC. Installing plastic piping is easier and less expensive than the standard metal flues used in conventional boilers.

For those of you who love the science behind the operation, just remember that the latent heat from the condensation provides around 970 Btu/Lb. of latent energy. This latent heat is what contributes to the increased efficiency, as this heat would otherwise be exhausted to the atmosphere. Boiler efficiency increases as the return water temperature decreases. Condensation occurs below 130F (54.4C), with the greatest efficiencies occurring the closer the return water gets to 60F (15.5C).

In commercial applications its best to get your supply temperature down to 140F (60C) as this provides an opportunity for better efficiencies. The engineer will have to make sure that the heat exchangers or whatever is receiving the heating hot water can operate at lower supply temperatures, as this will affect the surface areas of coils.

Considerations for Retrofitting a Non-condensing Boiler to a Condensing Boiler

Here are some main points to consider in commercial applications when retrofitting a project that has a conventional non-condensing boiler to a new condensing boiler.

Keep return water temperature as far below 130F (54.4C) as possible to take advantage of the increased efficiency at these lower temperatures.
Condensate drain piping with an inline filter to neutralize the acidic condensation. This includes the requirement for an approved drain receptor.
Boiler flue/stack to be installed using PVC or similar material
Heat Exchanger to be made of non-corrosive material, such as stainless.
Higher delta-T for existing fan coils or heat exchangers. Do they have the ability for lower flow (GPM) with greater temperature difference using a lower return temperature?
The old system might have been designed with a smaller Delta-T, maybe 20F (11C) (The difference between Supply & Return Water Temperatures). The new condensing boiler can run on a wider range of Delta-T, such as 30F to 50F (17C to 28C), allowing for lower GPM’s and pressure drops through heat exchangers. This saves on pump energy due to reduced flow and head.

Applications for using lower return water temperatures and a condensing boiler include, residential water heating and swimming pools, water-source heat pumps, hydronic radiant heating, snow-melt systems and geothermal.

How a Condensing Boiler Works

How Fan Coils Work in HVAC Systems

MEP Academy Instructor

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May 8, 2022

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How Fan Coils Work in HVAC Systems. In this article you’ll learn what a Fan Coil Unit (FCU) is, and where they’re mostly used in the commercial HVAC industry. We’ll cover the different types of fan coils, including 2-pipe, 4-pipe, horizontal and vertical.

If you prefer to watch the YouTube version of this presentation than scroll to the bottom for the video.

Fan Coil Components

Fan coils are very simple compared to other pieces of equipment. The fan coil contains a filter, fan, coil, and a drain pan to catch condensate from the cooling coil. The source of the heating and cooling is usually provided by a Chiller and Boiler located in a mechanical room, or outside on the roof.

Air enters the back of the fan coil and passes over filters before passing over the heating and cooling coils. The fan can be arranged in either a blow-through or draw-through configuration. With a blow through, the fan is before the coils, in a draw-through, the fan is after the coils.

The filters provide a means of keeping the air free of dust and particles, while preventing the coils from becoming clogged. The filter can be in a filter track attached at the back of the fan coil or a separate return air filter grill could be provided in the ceiling such as is common in some hotel room style installations using horizontal fan coils.

Depending on the size of the fan coil, there could be anywhere from one to three fans or more within the housing. These fans can be provided with ECM motors which make them energy efficient.

The fan coil will contain either one or two coils, depending on the design. There could be a heating and cooling coil installed, or just one coil for either heating or cooling. We are only discussing water-based fan coils, so refrigerant based DX coils are discussed in another article.

The cooling coil will require a drain pan to catch the water dripping off the coil. This is moisture that has been removed from the air and has condensed on the cold coil, much like you see condensate form on the outside of a glass of ice water. Its required to have drainpipe from this drain pan to an approved waste receptor, like a floor sink or the tailpipe of a sink.

How Vertical Fan Coils Work

Just like the vertical stacked Heat Pumps used in hotels, there are also Vertical Stacked Fan Coils. These vertically stacked fan coils can be either a two-pipe or four-pipe system. Using a 4-pipe system, there will be a chilled water and heating hot water supply and return piping, and of course a fifth pipe for condensate.

Vertical Stacked Fan Coil Unit FCU - High-Rise Hotel, Dorms, Apartments — Vertical Stacked Fan Coil Unit FCU – High-Rise Hotel, Dorms, Apartments

These vertical fan coils come with riser piping attached for easily stacking them one on top the other from floor to floor. These are best used in high-rise building such as hotels, condominiums, apartments, dormitories or similar high-rises.

Vertical Stacked Fan Coils in High-rise Hotel, Apartment or Dorm. (FCU)

Vertical fan coils are usually available from 3/4 ton to 4 Tons, or from 300 CFM to 1,600 CFM. The Chilled water entering temperature could range from 42F to 48F, with heating hot water entering temperatures of 120F to 180F. The units weight anywhere from 200 to 300 pounds.

How Horizontal Fan Coils Work in HVAC Systems

These Fan Coils use Chilled water or Heating Hot Water to provide the room with cooling or heating. A central ventilation unit will provide tempered air through a main duct to all the fan coils. This is the primary air supplied to the inlet of the fan coil to provide the required ventilation air (outside air) in accordance with ASHRAE 62.1. The fan coils reduce the amount of ductwork needed by the central system, because most of the heat transfer is done using water instead of air, by using Chilled Water or Heating Hot Water.

Horizontal 4-Pipe Fan Coil Units using a Chiller and Boiler

In the above image is a ducted return system where the supply air recirculates back into the fan coil. Some method of providing ventilation air will be required to meet code, which we’ll show shortly.

Fan coils provide both sensible and latent cooling, along with heating at the zone level, while the central ventilation unit conditions the outside air that feeds all zone fan coils.

Since the coils are very small in fan coil units, they’re not suited to handle large quantities of latent heat often brought in by ventilation or outside air. In these cases the use of a dedicated outside air system (DOAS) is recommended.

Fan coils can be either ducted or non-ducted and can be horizontal or vertical in configuration, and can be exposed or concealed.

Fan Coil Units with Dedicated Outside Air Systems (DOAS)

The benefit of using a DOAS is that the latent and sensible heat of the ventilation air can be handled by the Dedicated Outside Air System, while the fan coil will handle the load of the room it serves. This outdoor air can be decoupled from the fan coil units allowing any zones fan coil to be running at slow speed or be switched off when not in use, while still receiving ventilation air. Decoupled ventilation air means that the air from the outdoor air system is fed directly to the room without entering the fan coil unit, its totally independent of the FCU.

Horizontal Fan Coils with Dedicated Outside Air System

Fan coils are limited on their coil, fan and filter capacities. If the project requires additional heating or cooling capacity, then the use of a Blower Coil will provide the same benefits as a fan coil but with increased capacity. Blower coils come in larger CFM sizes, and higher static pressures, with coils that are larger and can provide additional heating or cooling capacity. These larger blower coils provide room for thicker filters, making for better filtration.

Horizontal Fan Coil with Chilled Water and Heating Hot Water Coils

Hope you enjoyed How Fan Coils Work in HVAC Systems, if you prefer to watch the video, see YouTube video below.

Learn How Fan Coils Work in HVAC Systems

How HVAC Heat Pumps Work

MEP Academy Instructor

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May 1, 2022

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We’ll cover How HVAC Heat Pumps Work, and the differences between an Air-Cooled and Water-Cooled Heat Pumps. We’ll explain the different styles of heat pumps used in residential and commercial buildings. You’ll learn the differences between air and water-cooled, packaged versus split systems, vertical versus horizontal, and ground and water source heat pumps.

If you prefer to watch the YouTube version of this presentation scroll to the bottom.

Refrigerant Cycle of a Heat Pump System – Reversing Valve

The Heat Pump has the same basic refrigeration circuit as a standard Air Conditioner except for a few specific components to help it succeed in both heating and cooling with the same refrigerant circuit. See our video on Refrigerant Circuits if you need a basic understanding on how they work. The main component that helps it function in both modes is the “Reversing Valve”.

Checkout these Heat Pumps here

Refrigerant Cycles - Standard Air Conditioner vs Heat Pump — Refrigerant Cycles – Standard Air Conditioner vs Heat Pump

The reversing valve has two modes of operation, its either in heating or cooling mode. The reversing valve provides changes in direction for the refrigerant flowing through the system, it reverses the flow, hence reversing valve. The reversing valve is the refrigerant traffic controller, changing the direction of refrigerant flow based on the demand of the space controller. The reversing valve sends the hot gas discharge from the compressor either to the outdoor unit heat exchanger or the indoor heat exchanger.

Reversing Valve in HVAC Heat Pump System

In relationship to the compressor, cooling is always accomplished on the suction side of the compressor, and heating is furnished on the discharge side. What the reversing valve does is switch the compressor discharge to go to the indoor coil when heating is required. It’s basically that simple, as the reversing valve acts as a traffic controller, sending refrigerant in one of two directions from the compressor.

To understand this better, we’ll walk through what happens in each season when heating or cooling is required.

Checkout these Heat Pumps here

Heating Mode

How HVAC Heat Pumps Work in Heating Mode. Starting at the compressor where the refrigerant is compressed causing the temperature and pressure of the refrigerant to increase. This high-pressure/high temperature gas (vapor) refrigerant will then enter the reversing valve where it will be directed to the indoor coil.

This high pressure, high temperature gas enters the indoor coil where cooler air from the space passes over the indoor coil absorbing some of the heat from the refrigerant, thereby heating the room, while causing the refrigerant gas to give up its heat and condense into a high-pressure liquid.

The refrigerant will than leave the indoor coil as a high-pressure liquid and enter the expansion valve where it’s pressure will be reduced causing it to become low-pressure liquid. See our video on expansion valves for more info.

This low-pressure liquid refrigerant will than enter the outdoor coil where it will absorb heat from the outdoors, causing the low-pressure liquid refrigerant in the outdoor coil to evaporate, absorbing the heat. This low-pressure refrigerant gas than enters the compressor where the cycle repeats itself.

Cooling Mode

How HVAC Heat Pumps Work in cooling mode, the heat pump acts the same as a standard air conditioners refrigerant cycle, whereby the condenser sends high pressure liquid to an expansion valve that lowers the pressure of the refrigerant going into the evaporator or indoor coil.

The heat from the space is passed over the indoor coil causing the refrigerant to boil or evaporate and absorb the heat from the air. This will cause the air to cool as its passes over the cold coil and head back to the space colder.

Checkout these Heat Pumps here

Packaged vs Split System Heat Pumps

You can get a Heat Pump that is all contained in one box, called a Packaged Heat Pump, or you can install it in two pieces which is called a split-system, and is commonly found in residential projects.

The split-system has an outdoor section, which houses the compressor and a heat exchanger with a fan in all air systems. The indoor section of a split system will have a heat exchanger and a fan. This is an all-air system, as each heat exchanger uses a fan. There are also water-sourced version which will cover now.

Water Source Heat Pumps

You’ll find the use of water source heat pumps in various sizes of commercial buildings. This allows for the use of a common water loop that works as a means of moving heat around. This heat can be discharged or absorbed from the water loop by the indoor heat pumps. The water loop is maintained between approximately 60 and 90 degrees. To help maintain the loop temperature within this temperature range a boiler is added to ensure enough heat is available during winter while the closed circuit cooling tower will reject additional heat during the summer or hot days.

The water is sent to a closed circuit cooling tower mounted outside on the ground or roof level. The water is in a closed loop, meaning that it never gets exposed to atmospheric elements. This keeps the heat exchangers of the water-cooled heat pumps clean by preventing impurities entering from exposed water sources.

With water-source heat pumps, heat rejection or absorption into the heat exchanger is through water. In an air-cooled system, a fan is used for heat transfer.

There are two commonly used types in the commercial industry, vertical and horizontal water source heat pumps, in addition to water source heat pumps used in ground source systems discussed later.

Vertically Stacked Water Source Heat Pumps

How HVAC Heat Pumps Work using vertically stacked units. There are lots of high-rise hotels that use vertically stacked water sourced heat pumps to provide heating or cooling to their guest-rooms. They are hidden behind the walls with a supply and return grill mounted to the face of the unit, and a temperature sensor nearby.

A vertically stacked water-source heat pump uses a closed-loop of water as a means of heat transfer. When in cooling mode the unit will reject its heat to the water loop, and while in heating mode it will absorb heat from the loop. The vertical heat pumps range in tonnage from 1/2 to 3 tons.

Vertical water source heat pumps contain the complete refrigerant circuit, with compressor, two heat exchangers, reversing valve and expansion valves.

Horizontal Water Source Heat Pumps

Various commercial buildings will have concealed horizontal water source heat pumps installed for each zone or room. These may also be found in hotel guestrooms, usually mounted above the entrance or bathroom with a stub of duct to feed a supply grille, with a ceiling mounted return grill. The return grill could also contain a filter.

These units are also available for exposed locations, usually near an exterior wall to provide a method for fresh air. Just like the vertical stacked heat pumps, these horizontal heat pumps will have a closed circuit cooling tower mounted outside.

Ground Source Heat Pumps

The sun shining on the ground provides for heat energy to be stored in the soil. This underground stored energy can be used with ground source heat pumps. With ground source heat pumps the ground is used as a means of absorbing heat or providing heat.

A pump circulates water through piping buried in the ground. This piping is connected to a heat exchanger in the heat pump where the heat from the ground will be absorbed or rejected into the refrigerant circuit.

Ground Water Source Heat Pumps

Bodies of water, like lakes or ground water can also be used as a source of energy. They use heat exchangers as a means of separating the refrigerant from the water. Water is mixed with antifreeze like glycol in some climates to avoid freezing and is pumped through a maze of hoses buried in the ground. The water circulates around the buried piping and then back to the heat exchanger where it transfers or absorbs heat from the refrigerant.

Ground - Water Source Heat Pump - Open Loop — Ground – Water Source Heat Pump (Open Loop)

When using groundwater, there are two types, the open loop which is shown here, and a closed loop version. The open loop system uses a pump to withdraw water from a lake or underground aquifer and send it through the heat exchanger where it will absorb or reject heat into the refrigerant before being sent back into the body of water.

In a closed loop system everything happens the same except the piping is closed and circulates the same water and antifreeze mix.

Water sources can provide a method of passive cooling, whereby the compressor can be shutoff.

Checkout these Heat Pumps here

How HVAC Heat Pumps Work in Residential and Commercial Buildings

How a Power Factor Works.

What is a Power Factor?

What Causes Reactive Power

AC Induction Motors

How to Correct Poor Power Factors

Why Correct the Power Factor?

Increased Available Power (kw)

Savings on Electric Utility Bills

Reduction in Cable Sizing

Reduction in Voltage Drop

Sizing of Capacitors for Correcting Power Factor

How Standard Boilers Work

How Condensing Boilers Work

Flue Gas Material

Considerations for Retrofitting a Non-condensing Boiler to a Condensing Boiler

Fan Coil Components

How Vertical Fan Coils Work

How Horizontal Fan Coils Work in HVAC Systems

Fan Coil Units with Dedicated Outside Air Systems (DOAS)

Refrigerant Cycle of a Heat Pump System – Reversing Valve

Heating Mode

Cooling Mode

Packaged vs Split System Heat Pumps

Water Source Heat Pumps

Vertically Stacked Water Source Heat Pumps

Horizontal Water Source Heat Pumps

Ground Source Heat Pumps

Ground Water Source Heat Pumps

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