talks/2025_Symposium
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
main
2025_Symposium/Presentation.md

14 KiB
Raw Permalink Blame History

autoscale: true footer: house 2025 Symposium slidenumbers: false build-lists: false theme: MacbookPro_Symposium.1

Are Chillers the Future

in Residential

[.footer:]

intro

^ Hello, I'm Michael Housh a contractor from the Cincinnati, Ohio area. Today we're here to talk about the viability of chillers in the residential market. This is a topic that I've been thinking about for the past 7 years. Disclaimer: All these are my thoughts and opinions, I do not have an inside scoop, I do not have a relationship with any manufacturer or distributor, I am just a dude from Ohio.

[.footer:]

It's not just because I like the art of piping systems


inline 120%

^ There's one primary reason that I believe that chillers are going to be the future in residential, can anyone guess that reason?

[.footer:]

flammable

Reasons

Change to flammable refrigerants in the future.1

^ This is just based on rumor, so timeline may vary.

[.footer:]

^ The goal of this talk is to introduce you to the concepts of chillers in general and to start to think through the pros and cons of such systems in the residential market here in the US.

https://app.mhoush.com

inline

^ I created a web app for this talk for you to document YOUR pros and cons throughout the talk, and hopefully we have time at the end to pick a few at random to discuss.

[.footer:]

^ Like any person who's never given a presentation before, I decided to ask Chat-GPT some questions. (move quickly through these next few slides). We'll start with the history of hydronic systems.

[.text: #ffffff, .text-scale(0.8)]

History

[.build-lists: false]

  • Dates back to Romans
  • 19th century, broader adoption due to cast iron radiators and steam boilers
  • 20th century, introduction of pumps, energy efficiency, zone controls
  • Popular choice for contemporary HVAC Systems

^ I find it interesting that hydronic systems / heating in general dates back to the Romans.

[.footer:]

^ Next, I asked Chat-GPT to define what a chiller is and how they're used.

Define Chillers

Chillers are mechanical devices used in heating, ventilation, and air conditioning (HVAC) systems to remove heat from a liquid via a vapor-compression or absorption refrigeration cycle.

Applications in HVAC

  1. Commercial Buildings:
    • Chillers are commonly found in shopping malls, office buildings, and hospitals, where they are used to cool large open spaces and maintain comfortable indoor temperatures.
  2. Industrial Processes:
    • Chillers are used to cool machinery and products, particularly in manufacturing processes that generate substantial amounts of heat.
  3. Air Conditioning Systems:
    • In large HVAC systems, chillers provide chilled water, which is then utilized by air handling units (AHUs) or fan coil units to cool air before it is distributed throughout the building.
  4. District Cooling:
    • Chillers are sometimes used in district cooling systems, where a central chiller plant provides chilled water to multiple buildings in a defined area.

^ Note how residential does not appear on the list.

What do we do?

^ Next, let's define what we do as HVAC technicians, designers, installers? Ask the audience to answer.

What do we do?

Provide healthy, safe, and comfortable environment.

What do we do?

  • We move heat from one place to another, generally through refrigerant and air circulation.
  • Water IS a refrigerant (R-718).

^ Second one is important to remember for later in the talk.

Fun Facts

Density Specific Heat
Air1 0.075lb/ft3 0.24btu/lb
Water2 62.37lb/ft3 1.0btu/lb

1Air density calculated for sea-level @ 70°. 2Water density calculated @ 60°.

https://hvacrschool.com/sensible-heat-in-air-and-water

^ As a fun fact, I stole this from an article I wrote for HVAC School named sensible-heat-in-air-and-water. Can anyone tell me why this matters?

Fun Facts

inline

Source: Modern Hydronic Heating, by: John Siegenthaler, P.E.

^ Add to pros list (hint)?

A Home is Complex

  • Shell / envelope
  • Ventilation / exhaust
  • Electrical
  • Plumbing / hot water
  • HVAC
  • and more...

A home requires harmony between many different mechanical systems.

^ (move quickly through these). I think it's important to note that a house is a complex thing, made up of a bunch of sub-systems that all need to be in harmony with each other.

[.footer-style: #696969, alignment(center)] [.footer: From: 'What if Houses Came with Manuals' by Sam Meyers and Genry Garcia] [.background-color: #d3d3d3]

fit

^ This image shows some of the different sub-systems of a house. I stole this from 'What if houses came with manuals' by Sam and Genry, but I created the original image, so it was fair game to steal ;)

[.footer:]

^ HVAC itself is also a complex beast.

HVAC Key Characteristics

A well-designed HVAC (Heating, Ventilation, and Air Conditioning) system provides several key benefits, including:

  1. Comfort:
    • Maintains a consistent and comfortable temperature and humidity levels throughout the space.
  2. Indoor Air Quality:
    • Improves air quality by filtering out pollutants, allergens, and other contaminants, while also providing proper ventilation to bring in fresh air.
  3. Energy Efficiency:
    • Optimizes energy use, reducing utility bills and energy waste through the use of energy-efficient equipment and proper system design.
  4. Zoning Control:
    • Allows for the creation of different temperature zones in larger buildings, enabling tailored comfort levels in different areas.

^ (move quickly). For me comfort and IAQ are the biggest ones I care about in this list. I feel energy efficiency is a side effect.

HVAC Key Characteristics

  1. Humidity Control:
    • Helps to regulate humidity levels, preventing issues such as mold growth and structural damage.
  2. Noise Reduction:
    • Designed to minimize operational noise, providing a quieter indoor environment.
  3. Reliability:
    • Incorporates durable components and proper system sizing to ensure consistent performance and reduce the likelihood of breakdowns.
  4. Scalability:
    • Can be designed to accommodate future expansion or changes in usage, making it flexible for evolving needs.

^ These are all really important aspects of an HVAC system.

HVAC Key Characteristics

  1. Automation and Smart Controls:
    • Integrates advanced controls and smart technology for optimized performance, scheduling, and remote management.
  2. Safety:
    • Incorporates safety features to prevent issues such as carbon monoxide buildup and gas leaks, ensuring safe operation.
  3. Maintenance Ease:
    • Designed for easy access to components for routine maintenance, inspections, and repairs.
  4. Environmental Responsibility:
    • Utilizes eco-friendly refrigerants and practices to minimize environmental impact.

A well-designed HVAC system is essential for providing a comfortable, healthy, and efficient indoor environment.

fit

^ Let's look at a well designed conventional HVAC system. It incorporates all the things listed in the previous slides.

[.footer:]

^ So, what are some key differences between a conventional HVAC system and one that utilizes a chiller?

Key Differences

Here are some key benefits:

  1. Energy Efficiency:
    • Chillers, especially when combined with modern controls and variable frequency drives, can be more energy-efficient than conventional HVAC systems. They often consume less energy, leading to lower operating costs.
  2. Scalability:
    • Chiller systems can be easily scaled to meet varying cooling loads. You can add or remove chillers based on demand, making them suitable for buildings with fluctuating cooling needs.
  3. Flexibility:
    • Chillers can provide cooling for multiple spaces or zones within a facility efficiently and can be used in a variety of applications, including process cooling and specialized environments.
  4. Integration with Renewable Energy:
    • Chiller systems can be integrated with renewable energy sources, such as solar or wind, enhancing their overall efficiency and sustainability.
  5. Water-Cooled Options:
    • Many chiller systems are water-cooled, which can be more efficient than air-cooled systems, particularly in larger settings. Water has a higher thermal capacity than air, leading to more effective heat exchange.

Chiller systems offer several advantages over traditional HVAC systems.

^ (move quickly).

Key Differences

  1. Reduced Environmental Impact:
    • Chillers can use refrigerants that have less environmental impact compared to some traditional HVAC systems. They can also be designed to minimize energy consumption, further reducing their carbon footprint.
  2. Consistent Temperature Control:
    • Chillers provide more consistent cooling due to their ability to modulate cooling output based on demand, leading to improved comfort in living and working environments.
  3. Space Saving:
    • In certain applications, chillers can save on space by centralizing cooling. They can be placed away from conditioned spaces, whereas traditional systems may require larger equipment to be located within these spaces.
  4. Longevity and Reliability:
    • Chiller systems are generally robust and, if properly maintained, can have a longer lifespan than traditional HVAC units. Their design often allows for easier maintenance and repair.
  5. Advanced Control Systems:
    • Chiller systems often incorporate advanced building management systems, enabling better monitoring, automation, and integration with other building systems for improved overall performance.

^ (move quickly). Not sure I agree with space saving and we'll see why in some future slides. Longevity seems interesting. Once again these are all sort of geared / speak towards commercial buildings.

fit

^ (begin the meat & potatoes of the presentation). Now let's begin to discuss the super-powers that chillers can unlock in the residential market.

^ Here's an image of an air -> water heat recovery chiller. It should be noted that through this talk when I say chiller, I'm generally referring to a heat recovery chiller, which is a specialized sub-set that can do simultaneous heating and cooling. These are hard to find in small tonnage chillers, but hopefully that changes if more major manufacturer's come around to this idea. (Major manufacturer representation is one of the cons). Note: I like to call the equipment that provides the hot or chilled water as the "plant".

^ Let's look at some of the internal components. I like to call these internal components the "infrastructure". These components should generally have a significantly longer life expectancy than the "plant" may have. Also note that buffer tanks come in a variety of different sizes depending on the application.

^ The AHU's are similar to traditional ones, however in place of where electric heat strips would be, it's replaced with a hot water coil. This opens up the door for reheat dehumidification as a standard option. Note that I believe that air circulation is still an important part, although these systems do allow for radiant heating / cooling, I personally believe that moving air is generally the best choice. I also think that one of the downsides of conventional inverter systems (which I love don't get me wrong) are that we don't move enough air in a home, but that's a topic for another day / talk. ;)

^ Do you like ductless style AHU's, well they've got those too for hydronic systems.

^ These systems are still highly capable of dual fuel applications.

^ In fact, they are highly extensible / scalable to incorporate many different "plants". This shows a wood boiler that can also be incorporated to generate heat that the "infrastructure" could then utilize.

^ Are you in a climate that has significantly higher heating loads? Or an application where redundancy is important? Incorporate several units (only showing 2) to increase the capacity and have "fail over".

Other Capabilities

  • Control the water temperature based on outdoor conditions.
  • Use off-peak rates to store water in buffer tanks (may dictate buffer tank sizing).
  • Dump heat into a pool / spa.

fill right

Other Capabilities

  • Low latent load?
  • Target supply temperature during reheat.
  • Utilize current controls that are designed for boilers.

fit right

[.text: #ffffff, text-scale(0.8)]

Cons

  • Higher upfront costs.
  • More in-depth design requirements (maybe a pro as well).
    1. Distribution systems need designed to handle low water temps.
    2. Not a drop in replacement for existing boiler systems.
  • Challenge where pex / copper lines can't be ran.

Cons

  • Lack of major brands.
    1. Chilltrix
    2. Daikin
    3. LG
    4. Multi-Aqua (only heat recovery option I know of, but only 5-Tons)
    5. Spacepak
    6. Taco (integrated buffer tank / DHW)
    7. Viessman (now owned by Carrier).

Your Pros vs. Cons

^ Pull random list of pros vs. cons that the audience has created to highlight a few.

Thank You!

  1. Projected to change refrigerants again in the next 10-15 years. ↩︎

Reference in New Issue View Git Blame Copy Permalink