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:
- Durability and Appearance
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.
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
- All heat pumps, boilers, air handlers, and any other active equipment being controlled in the HVAC system.
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
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.
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.
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.
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.
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.