Posts Tagged ‘geothermal’

Hydronic Control Panels – What You Should Expect to Find.

Monday, January 9th, 2012

Hydronic Control Panels
What should you expect to find in a control panel?

WHAT IS THE VALUE OF A HYDRONIC CONTROL PANEL?

The control panel is the heart of the hydronic system. It should include all components that are not only compatible with the rest of the equipment connected to the HVAC system but allow the system to provide optimal performance. It should be easy to install. It should include all mechanical and electrical connection points. It must provide equipment that protects both the system and the home in case of equipment malfunctions. It should provide for ease of serviceability during routine and emergency maintenance. As it is perhaps the most visible system component in a customer installation, it should also provide a clean and professional appearance.

When considering a hydronic control panel design, the following should be taken into consideration:

  • Functionality
  • Installation
  • Durability and Appearance
  • Serviceability

FUNCTIONALITY

By definition the control panel is the main system component where the hydronic system should be controlled or operated from. This means that it should include as many of the system control elements as possible as well as be the electrical center for all equipment attached to the hydronic system.
Standard elements that should be included in a control panel design include: feed water regulator and backflow preventer, expansion tank, air eliminator, zone valves, circulating pumps, pressure gauge, temperature measurement for supply and return with delta, system controls, master power switch, electrical wiring connection points, and fill and flush connections.

Visio-showroom panel labeled.vsd

Basic Elements of a Hydronic Control Panel

Other items that can be included:

  • Fittings for a variety of piping types
  • Strainer or Dirt Separator
  • 3-way or variable speed mixing
  • DHW Piping and controls
  • Heat Exchangers
  • Glycol Feeders

Integrated Control Options

  • Variable Speed Mixing
  • Setpoint Controls
  • Ice and Snow Melting
  • Ecô Energy Management System

Wiring Connection Terminations for:

  • All thermostats and sensors
  • Circulation pumps
  • Actuators
  • All heat pumps, boilers, air handlers, and any other active equipment being controlled in the HVAC system.

INSTALLATION

As all control panels are essentially customized to a specific installation, the contractor essentially has two choices:

Option 1 – Build it on-site:

  • Pre-design or design-on-the-fly
  • Specify and obtain components
  • Work in potentially unconditioned and uncontrolled environment
  • Incur travel & labor costs
  • Test system on site
  • Make any revisions to panel at on-site labor costs plus travel

There are a lot of variables in this equation. Even with experienced personnel, costs can be unpredictable and difficult to control.

Option 2 – Have it designed and fabricated off-site for easy and quick installation:

Using Eagle Mountain/Hydronic Systems this provides the following advantages:

  • Full Control panel is designed and reviewed ahead of time for physical layout, components, connectivity, wiring layout, and panel size – before any fabrication begins.
  • Panel is fabricated in a controlled environment at factory labor rates.
  • All electrical control connection points are brought to a single electrical box mounted on the panel.
  • Panel is tested before leaving the factory.
  • The only labor required on the job site is for mounting the panel and making the physical connections to the rest of the system.
  • Cost of the panel is known up-front. Installation costs are not only predictable and more easily controlled, they are also greatly reduced.

DURABILITY AND APPEARANCE

Panel Material
It is common to find control panels mounted on materials ranging from plywood to steel sheets. While these materials are readily available and may be relatively inexpensive, they are not ideal for hydronic systems. By their nature, hydronic systems involve water. Components can collect moisture on external surfaces that eventually can migrate to other components in the system. This moisture will eventually weaken and warp wood materials potentially compromising the structural integrity of the control panel. Similarly, steel sheets may be subject to corrosion that may also bring similar risks to the structural integrity of the overall control panel.

An ideal material for control panels is a high-density polyethylene (HDPE) board. This material provides adequate strength and stiffness to accommodate all the control panel components, is completely impervious to the effects of moisture, and also provides a professional appearance in the home or facility where the control panel is mounted.

Panel Mounting
Any prefabricated panel should come with a mounting system that allows for simple and quick wall-mounting by one or two people (depending on the size of the panel). Connection to the rest of the system should be simple and easily accomplished once the board is mounted. Remember, one of the primary purposes of the prefabricated hydronic control panel is to reduce on-site labor.

Copper and Brass Handling
During fabrication, the copper and brass components should not be touched by hand due to the salts on the skin, or exposed to environments that can produce oxidation. Fabrication should be done using gloves designed for handling copper and brass that eliminate the salts transfer.

Cleaning
The piping and fittings need to be cleaned of the flux material used during the assembly to prohibit accelerated corrosion of the copper. The copper may also have surface oxidation from the assembly process as well as salts from shipping and/or handling of the copper by hand. These salts will accelerate the oxidation producing discoloration and eventually corrosion of the copper and brass components in the system. The panel should be thoroughly cleaned and polished to prevent any corrosion of the components.

Following installation, the control panel is perhaps the most visible component to any hydronic-based HVAC system. In addition to the serviceability issues discussed above, the value of a clean and well organized control panel that will stand the test of time should serve any contractor well as a showpiece for the type of installation and work that potential customers can expect from them.

SERVICEABILITY

Next to the ease of installation, the most significant criteria in control panel design have to do with serviceability. As the system is mechanical in nature, over time there is a significant likelihood that maintenance of some sort will be required. Chances are, if a service call is required, the first place a technician will need to go is the control panel. A well-designed control panel allows for easy access to all of the system controls in a consistent manner and provides appropriate access to all components. This design should include removable actuators and sufficient valves and drains to isolate any component for service or easy replacement.

Another benefit inherent with pre-fabricated control panels is that the contractor will have access to a drawing of the control panel available to them to review in the event of a service call. Having this information available will help technicians with remote trouble-shooting and save money in service calls benefitting both the business and their customers.

SUMMARY

Together, all of the elements discussed above add up to the value that the hydronic control panel can bring to your business. Each of these elements is important to both the contractor and the end-user. The decisions made around the design and installation of the hydronic control panel can have both immediate and long-term impact to the system functionality as well as to the relationship between the contractor and the system owner. Care should be taken to consider future maintenance as well as potential changes to the system. Weight should be given to the desired optimal performance of the system when determining system components and layout. All electrical wiring and controls need to be taken into account when designing and evaluating control panel solutions. Eagle Mountain’s hydronic control panels provide a high-value solution to any hydronic-based HVAC system.

Geothermal Case Study: Center for Green Technology

Friday, October 8th, 2010

Eagle Mountain’s Center for Green Technology is a revolutionary facility that demonstrates a commitment to environmental conservation, and is a showcase for the companies’ line of alternative energy products.

Environmental Innovation

The Center for Green Technology is dedicated to research and development of green technology, making alternative energy HVAC products more efficient and available to a larger market of consumers.

The facility uses a Geothermal HVAC system with radiant heating and intelligent climate control.  Multiple loopfields and independent geothermal heat pumps allow Eagle Mountain engineers to study and improve the integration of geothermal heating equipment.

Resource Reduction

The Center for Green Technology and Innovation is dedicated to geothermal heating and cooling, solar, and wind, all of which harness naturally abundant energy sources and significantly reduce consumption of non-renewable resources.

Alternative Energy Use

The Center for Green Technology uses alternative energy to heat and cool its 21,000 square foot facility. Geothermal heat pumps exchange heat between a pond and the building, providing energy efficient heating and cooling.

Green Building

The Center for Green Technology uses existing technology to dramatically lower energy costs, uses sustainable and reusable building products, and reduces environmental impact. The project demonstrates how green building can be accomplished at a cost similar to traditional commercial construction.

Abundant Natural Light

Abundant Natural Light

The facility includes “green” building principles such as:

  • Special window glazing
  • Strategic skylights and windows to reduce lighting requirements
  • Motion activated light switches
  • Insulated concrete form (ICF) construction
  • A rainwater collection system
  • Water-less urinals
  • Recycled blue jean insulation

Solar Powered Sink

Waterless Urinals

Long-term Commitment to Conservation

Energy consumption at the Center for Green Technology is less than half that of a typical building of the same size.  Programs and services teach customers, employees, and the community how business can meet the profit demands of a business and the ethical demands of environmental conservation.

Classroom

Classroom

Geothermal HVAC System

The Center for Green Technology uses water-to-water geothermal heat pumps with a pond loop and a horizontal slinky ground loop. Radiant floors heat the building during winter months, and air handlers cool the building during summer months.  The building uses heat recovery ventilation (HRV) and Eagle Mountain’s Ecô energy management system to manage and optimize energy consumption.

Heat Recovery Ventilation (HRV)

Heat Recovery Ventilation (HRV)

Interview with Doug Mossbrook
CEO of Eagle Mountain and designer of the Center for Green Technology.

Doug Mossbrook

1. Did the building receive LEED certification? If so, when and what
certification level?
The LEED process is still underway. At this point the building score should easily qualify for LEED Gold.

2. How long did it take the building to be constructed? 24 months

3. How much energy is the building saving when compared to a
traditional building of the same size?
Our building modeling is estimated at 49% reduction of energy use. We will be monitoring the actual energy use with our new Ecô Energy Management System that we developed. Then we can match estimated performance with actual.

4. I read about the training center in a local newspaper article. Doug
mentions that he envisions seminars for local colleges, and for trades
people to gain certification? Has there been any opportunity to host
seminars/certifications yet?
We have been providing geothermal training for our national dealer network bi-monthly since Spring 2009. We are working with the local community college on a program as part of their sustainability program. We would also like to host some of the RPA and IGSHPA training classes here at our facility.

5. How is solar and wind being used to harness energy at the site? The upper roof area has been prepared to hold 8 solar thermal panels and 22 solar pv panels. The 10 Kilowatt wind generator was pulled from the building site plan due to a town moratorium on wind generators. Since we are in a valley the wind generator was to be used for demonstration purposes anyway. We intend to move forward with the zoning work to get approval in the future.

6. Do you believe green building can be accomplished economically? Why or why not? It sounds like the cost of this building was in line with the cost of building traditional. I not only believe it, I proved it. I was able to build this project for a cost of $100 per square foot.

7. What type of rainwater collection system is being used? We collect the rainwater from our roof drains and filter it using 2 – vortex filters made by Wisy brand products from Germany. The water is collected in an underground storage tank, and is used for all of our toilets and faucets used for washing trucks and equipment.

8. What type of low-flow plumbing fixtures are being used? We used Sloan low-flow toilets and waterless urinals.

9. Why did you decide to put a green roof on the building? Is it the
entire building roof or just part of the building roof?
I felt the green roof could help the building blend into the natural environment on this site, created a nice patio area as a workspace, and I was
interested in the thermal performance from a research standpoint. Due to cost, we only have 3600 sf of green roof area. I wish I had done the whole roof. That section, which is over the education wing, uses much less energy for heating and cooling.

10. How is the training center teaching the community about
sustainability and conservation?
We are putting together a three-part educational seminar series that would be offered free to the public. The focus would be on alternative energy systems and sustainable
methods. The first program will be on solar and wind technologies, and we expect to start the 3-month series next spring.

11. What type of classes seminars are taking place at the training
center?
Geothermal, solar, wind systems, sustainable building methods and technology, rainwater collection, just to name a few.

12. What are your future goals for the training center? Our goal is to become a leader in industry and community based educational programs, that provide people ideas and skills to enable them and promote change.

About Eagle Mountain

Eagle Mountain is an alternative energy integrator specializing in radiant heating, geothermal heating and cooling, and energy management systems.  Eagle Mountain distributes its products under the Radiantmax, Geomax, and Ecô brand names. As a boutique supplier of integrated systems, Eagle Mountain has customers located throughout the world and is based at the 21,000 sf Center for Green Technology in Bristol, NY.

Customer: Center for Green Technology

Location: Canandaigua, NY

Project: Geothermal HVAC system with water-to-water heat pumps and radiant distribution.

Web: www.eagle-mt.com

Installer: Geocorp

Can you use Geothermal with Baseboard Radiant Heating?

Tuesday, August 31st, 2010
Boug Mossbrook

Doug Mossbrook

Yes, it’s technically possible, but the answer is NO.

We had a customer write in saying “At my IGSHPA training the instructor told us that using geothermal with baseboard radiant absolutely could be done -because the plumbers used to always oversize the baseboard runs anyway -maxing them out per room -so the lower 120 degree water temp would work.  I would like to know what the engineers up your way say about this.”

The short answer is no, don’t use geothermal with baseboard heating or radiators.

The longer answer is yes, but with a few caveats that will be explained here.  Baseboard heaters use convection heating to heat a room. There are typically fins inside the heater called elements. These elements have a set resistance, which transfers heat energy from the hot water and dissipates it in the form of heat to the surrounding air.

Because the warm air is lighter than the cooler air, it rises out of the top of the heater and the cooler air closer to the floor is drawn in from the bottom to replace the displaced warm air. This is convection.  This cycle continues until the air surrounding your control center or thermostat reaches the specified temperature.

Convection

Convection

The typical operating temperature of water in a baseboard heating system is roughly 160 – 180 degrees fahrenheit.  This high temperature is critical to be as efficient as possible.

Convection does not work with low temperature water from a geothermal heat pump.

And as we all know, a geothermal system is a low temperature heat source, with a maximum output temperature of roughly 115 degrees.  With radiant floor heating or forced air, this water temperature is perfect to heat a room, and it helps keep the geo system as efficient as possible.

115 degree water is not hot enough to adequately dissipate heat for baseboard hydronic systems.  It will dissipate some heat through the fins simply because the water in the pipes is warmer than the room; however, to heat a room to 70 degrees will take a long time, require a lot of energy, and additional surface area (more radiators).

The technical answer whether or not baseboard radiant works with geothermal is yes; however the cost of additional radiators, piping, and reduced efficiency make the correct answer no.  Baseboard radiant is most efficient when incorporated with a boiler system.  A boiler radiant heating system is capable of much higher output temperatures than a geothermal system.

Geothermal Case Study: Red Tail Ridge

Tuesday, June 15th, 2010
Red Tail Ridge

Red Tail Ridge

Customer: Geocorp

Location: Penn Yan, NY

Project: Red Tail Ridge Winery: HVAC and Wine Process Cooling with: Geothermal, Radiant, HRV, Energy Management

Web:

redtailridgewinery.com


Red Tail Ridge is a Finger Lakes winery using an Eagle Mountain geothermal system for HVAC and process cooling.

An industry leader in sustainability and innovation, the new facility at Red Tail Ridge will be LEED certified and delivers a 40.1% total energy savings.  The system components include geothermal, radiant heating, heat recovery ventilation, and Ecô energy management.

System Background

The system design calls for a 20-ton closed-loop geothermal heat pump system to heat and cool the building, and to provide chilled water for process cooling. The system consists of four (4) 5-ton Cascade water-to-water heat pumps, a horizontal closed-loop “GeoSlinky” ground loop heat exchanger, and a custom Hydronic Control Panel.

Geothermal Heat Pumps

Two geothermal heat pumps are dedicated to space heating and cooling. Radiant floor heating is installed in the process, case and barrel storage, and bottling areas. A fan coil unit provides for cooling and heating loads in the laboratory located on the mezzanine level.

The other two water-to-water heat pumps generate chilled propylene glycol to meet the process cooling requirements of winemaking.

Horizontal Slinky Loop

The horizontal slinky loop consists of eight trenches, each 130 feet long with 4 feet spacing between each trench. The slinky coil is 34- inches in diameter with 18-inches of pitch. A propylene glycol solution is circulated through the ground loop heat exchanger and the water-source heat pumps by a variable flow/variable speed loop pumping system.

Heat Recovery Ventilation

Ventilation air will be introduced into the building through a heat recovery ventilator (HRV). The HRV includes a flat plate heat exchanger that transfers energy between building exhaust and outdoor air streams.

Control System

The entire HVAC system including wine process cooling is controlled by Eagle Mountain’s Ecô energy management system.  This “virtual control device” replaces all hardware control devices and is accessible from any Internet connection in the world.

The Ecô energy management system has additional benefits for Winemakers.  This browser-based system allows the Winemaker to control and monitor the winemaking process remotely. Ecô provides Winemakers an innovative alternative to manual operation of the Winemaking process.

Click to learn more about The Ecô energy management system.

Design & Installation

Eagle Mountain specified the system design, integrated and supplied all components, and provided consulting services for the application of geothermal technologies for LEED certification.

Geocorp, an alternative energy installer located in Western New York, installed the system at Red Tail Ridge.

Process to change Geothermal from Heating to Cooling

Monday, June 7th, 2010
Jason Murphy

Jason Murphy

Geothermal systems provide both heating and cooling.

If you have a forced-air geothermal system using a water-to-air geothermal heat pump, simply change your thermostats from heating to cooling mode, and you are done. Forced-air geothermal systems are the easiest to change from heating to cooling mode.

Cooling with Hydronic Geothermal Heat Pumps

If you have a radiant heating system, your hydronic geothermal heat pump provides cooling via high-velocity or low-velocity air handlers.

Step 1: Locate your Hydronic Control Panel


If you have a hydronic system, the first step is to locate your hyrdonic control panel in the mechanical room.  You control panel will look like this:

Hydronic Control Panel

Hydronic Control Panel

Step 2: Determine if you have 1 or 2 Tekmar Controls


The device that tells your heat pump to make either hot or cold water is a Tekmar 152 two stage setpoint control.  Your control panel will either have one or two Tekmar controls.

(more…)

Geothermal Radiant Heating Systems

Tuesday, May 11th, 2010
Dan Frawley

Dan Frawley

Lessons Learned by Dan Frawley

Eagle Mountain is an alternative energy integrator. In plain and simple terms we are experts at combining multiple systems together. A prime example of this is pairing a geothermal heating system with radiant heat delivery. This type of system is something that we get inquiries about all the time.

Most people are under the impression that you cannot combine these two types of systems. They think that because a geothermal system is a low temperature heat source, radiant would not be a viable heat delivery method.

Those people would be wrong.

Geothermal heating with radiant is a great way to heat your home. You get all the benefits of radiant heat combined with all the benefits of Geothermal. The most common implementation of geothermal radiant heat systems is in a new build, but it is fairly common to have inquiries in regards to retrofits. Retrofitting geothermal with radiant poses its own set of issues and there are some common misconceptions that go along with that.

(more…)

Geothermal Tax Credit Explained

Monday, May 10th, 2010
Jason Murphy

Jason Murphy

A geothermal tax credit of 30% of the total system price is available for systems using qualified geothermal heat pumps.

In October 2008, geothermal heat pumps were added to section 25D of the Internal Revenue Code. This created a 30% federal geothermal tax credit for costs associated with qualified geothermal equipment “placed in service” through the end of 2016.

Equipment is usually considered to be placed into service when installation is complete and equipment is ready for use, or for new construction, when the owner takes residence.

Geothermal Tax Credit Overview

• 30% of total system cost
• No limit to credit amount for 2009 and beyond
• Can be used to offset AMT tax
• Can be used in more than one year
• Can be combined with solar and wind tax credits
• Can be combined with energy efficiency upgrade credits

What’s Eligible?

(more…)

Install Geothermal Heat Pump in the Attic

Monday, March 29th, 2010
Dan Frawley

Dan Frawley

Where do you put your geothermal heat pump if you are building a home with a crawl space, or it is slab on grade and you do not have a large enough mechanical room?  Where do you put your geothermal heat pump if you are retrofitting your home for geothermal HVAC and have no room in your basement or existing mechanical room?

These, among others, are very important questions to ask before you begin your geothermal installation.  The location of the heat pump is crucial to know before you even put your project in the hands of the engineers and designers here at Eagle Mountain. Placement affects pump pack size, supply and return size, etc.  Where can you locate the heat pump?  An option is in a space that is normally used for storage, the attic.

The problem with this answer lies in whether or not your attic is a conditioned space or not.  The general rule of thumb for a geothermal heat pump is that it must be placed in a conditioned space.  The solution to the problem of placing a heat pump in an unconditioned attic is, what we call here at Eagle Mountain, a hot box.

Hot Box

Hot Box

The “Hot Box” can be essentially a 2×4 framed container that is sheathed in plywood with a removable top to create easy access for service. Once the container is built around the heat pump, you lay insulation across the attic floor and around the outside of the box.  This creates a conditioned space for the heat pump to sit in, essentially making that space part of the house, or heated space.

This “Hot Box” solution allows for two things.  First, it allows the heat pump to be placed in a conditioned space for optimal performance and efficiency.  Secondly, it allows the attic to remain unconditioned to conform to the outdoor temperature.  This is important, especially in winter, if ice damage is a concern.  Also, the attic will not be comfortable in the winter and then uncomfortably warm in the summer.  It is also important to note that piping from your geothermal loopfield to the heat pump must be insulated and contain the correct propylene glycol mixture for geothermal systems.

Propylene Glycol Mixture: Geothermal Freeze Protection

Monday, March 29th, 2010

Our installers often ask why we recommend a 25% mixture of propylene glycol to water for geothermal loopfields.

Propylene glycol at a 25% mixture by mass yields a freezing point of about 12.5 degrees F. Since propylene glycol is slightly more dense, 1.036 g/cm3 to 1.0 g/cm3 for water, this equates to a mixture by volume of 25% freezing at 12.95 degrees F. 20% by mass freezes at 18 degrees F. This is sufficient for interior hydronic lines.

Our pump sizing is based on the viscosity of a 25% glycol mixture by volume. We use this mixture because it uses the minimum amount of glycol for pumping viscosity losses while providing freeze protection.

The reynolds number also plays a part in the ratio. The greater the volume of the thicker glycol, the faster you have to pump to reach turbulent flow. Use 25% glycol to 75% water with our product in a correctly designed geothermal loop field for optimum performance.

Since our product is inhibited, it has a glycol ratio of 96%.  Four percent is the additives for corrosion resistance and the anti-foaming agent. This is the highest ratio available in this type of glycol. Some products labeled -100 can be as low as 65%. If you mix that at 25% you would actually be only 16.25%.

Download the Freeze Safe 100 PDF Spec Sheet for more information.