[00:00:03] Speaker A: Hello and welcome to the Consulting Specifying Engineer podcast. I'm your host Anna Steingruber and today we will be joined by Ronald Reuss to discuss single to discuss single phase heat pumps. The decarbonization movement has placed single phase heat pumps at the forefront of both residential and light commercial building design. Higher efficiencies, lower operating ranges and multi zone capabilities of many variables. Refrigerant flow or VRF has long been a viable alternative to conventional small split heat pumps. However, native VRF controls have been limited in the past. As we look toward the future, VRF systems continue to be a popular choice, providing a flexible, versatile solution that is ideal for a wide range of structures and industries. This will help mechanical engineers identify how VRF technology can help build better airflow systems and building design.
To discuss this topic today we have Ronald Reuss. Ronald is a Senior Manager for Engineered Sales with Linux International and he focuses specifically on variable refrigerant flow with clients across the United States and Canada. Welcome to the podcast, Ronald, and thanks for joining us.
[00:01:10] Speaker B: Thank you very much for having me.
[00:01:13] Speaker A: Great. So before we get started with any of the hard hitting engineering questions, I've been told that you're originally from South Africa. Can you tell me what the biggest culture shock or difference has been between South South Africa and the U.S.
[00:01:27] Speaker B: That'S, that's a good question.
There's been a number of culture shocks. I'd say the biggest one for me and my family has been really the food.
There is such an abundance of different food options and wherever I go in the US and Canada, it's always a little bit different, but it's not quite like it is at home. I mean, you know, just from the delicacies we're used to, the seafood, everything is a little bit different. So I would say that's, that was the number one shock for us outside of, you know, just the different cultures around the US I wonder if, if people from the US natively realize how culturally diverse the US and Canada is. Really, it's always, is always nice. My, my overarching theme is North Americans are by association usually friendly, upbeat, and I, you know, by far, based on my travels, it's been a great experience being on this continent. So great question. Thank you.
[00:02:24] Speaker A: Yeah. Well, I'm glad to hear that we are all friendly. I'm going to tell everybody that I know that other people think that we're friendly and great now. So thank you for that.
To get kind of into this, can you give me a broad overview of single phase heat pumps and how they've become so popular.
[00:02:39] Speaker B: Absolutely, that's, that's a good segue for us as we have some conversations around this topic. So single phase heat pumps have been around for a very long time, but the prominence have really increased over the last just, you know, few couple of years. And the reason for heat pump especially being so much more prominent is the development of technology and how far it's come over the last couple of years. Efficiencies of lower ambient conditions and the ability to produce heat, making it a viable option in colder climates has really been the biggest push around that technology.
Now, of course, single phase heat pumps essentially means an outdoor unit and an indoor unit connected with refrigerant piping, with the thermostat, with the ability to both heat and cool. That is essentially technology as a whole. And really what's broadened that piece is that indoor units capability to produce that heat under all these climates have been a big driving force, especially with the decarbonization movement.
[00:03:39] Speaker A: And so you work for Lennox. Can you tell me what technologies Lennox supports specifically is working on in the VRF space?
[00:03:48] Speaker B: Yes, absolutely. So, you know, right now our latest and greatest piece of technology and our expansion of our VRF power portfolio is the Lennox Real Mini VRF Outdoor Units.
We've done away with the VRF acronym for them because of the ability for these units to function both as a traditional heat pump and as a VRF style outdoor unit with variable capacity.
So from a Lennox perspective, we look at what we do well in the market. We are one of the core players in Single Phase Heat Month for both residential and light commercial use. With our conventional machines really being the cornerstone of our business, with VRF being one of the cornerstones of our commercial business, we thought about the product development and realized if we propose a marriage between the two products and give them the ability to work together in harmony, that gives our customers and at the end users the opportunity to realize the benefits of all of the Linux traditional products, plus the VRF products and the efficiencies they bring. So from that perspective, that would be our core piece of new products right now is the Lennox Real Outdoor units. And our focus continues to be in variable speed compression technology and low ambient heat bumps. So in the future you're going to see more of these products hit the market as we focus on the decarbonization movement and making, you know, energy efficiency and really how that impacts our customers and the environment.
[00:05:21] Speaker A: Yeah. And so since this product was designed with VRF technology, which is normally known for being Very efficient. How does the system operate? Standard 24 volt thermostats?
[00:05:32] Speaker B: That's a great question.
Because in the past VRF technology has not played well with conventional communication and conventional thermostats. So that was one of the challenges that we faced with this marriage of our traditional and VRF technologies is how do we make it work? How do we get these two fundamentally different products to play well together?
And the way we've done that is by writing an algorithm in the outdoor unit and really looking at that controls piece. How do we make that single outdoor unit, that heat pump, be able to work with really anything connected to it? And we thought about it by breaking it down into principles, into really thinking about how we communicate. So by leveraging the conventional 24 volt thermostat communication of Y1, Y2 and so on, that standard means of communication, while also understanding how that's going to impact the compressor and how it operates, we built in a conversion board inside the outdoor unit that will receive a signal for call for cooling or heating from the indoor unit directly based on conventional thermostat wiring, that then sends the signal into the outdoor unit to say, all right, I have a call for cooling. Now what?
So what the algorithm internally to the outdoor unit will then do is measure superheat temperature in the compressor as it operates in that refrigerant cycle. By measuring that and maintaining and controlling to a fixed parameter within the outdoor unit, the compressor is able, even with just a base call for cooling, to modulate the compressor based on the superheat temperature and in doing so, also modulate the condensing unit fan. Meaning we maximize efficiency and retain the VRF technology's ability to really optimize performance based on a call for cooling and heating, while taking the controls that are usually positioned in the indoor units and moving it just to that sole position in the outdoor unit. But we didn't stop there. We took a look at this and said, all right, this is a fantastic means of doing one to one connections where you don't need any fancy communication protocols or boards or anything in between.
Standard outdoor unit. A standard indoor unit, a conventional indoor unit could be any brand with a Lennox real outdoor unit giving you that efficiency.
But what if you wanted multiple of them? For example, in that instance, we've developed a little board giving us the ability with an electronic expansion valve in this board, to communicate and operate multiple units on this same outdoor unit. Because it is still VRF technology.
Meaning I can put up to nine indoor units, mix and match indoor units or connect them one to one while leveraging 24 volt communication.
So essentially taking a traditional heat pump single phase system, a VRF single phase system, some of the ductless split systems and putting everything in one bucket with one single outdoor unit able to do all of these things, that gives more options back to the customers.
[00:08:49] Speaker A: And so what are some common applications for Linux Real?
[00:08:54] Speaker B: That's a great question. At the end of the day it's all about applications. It's about where this product and really all of Linux products fit within a customer's portfolio.
From an engineer perspective, we understand that our engineers develop and work on multitude of projects across the different landscapes. Letics Real is uniquely suited to really play well in the bulk, if not all application and verticals that are out there. But where it plays and really gets defined as being a needle mover, if you will, is on the residential side of the world where lot lines, low noise and space constraints are a real issue, especially in residential new construction. At that point, Lennox Reel Inside Discharge with low noise is a fantastic application.
If you look at multi family use, this is still a VRF outdoor unit by nature.
With its 10 year warranty and the ability for this unit to run really long runs of pipework, it means it can be used on a 10 plus story multifamily application where every suite is being given, let's say for example a one and a half ton outdoor unit connected to let's say two or three indoor units.
that point you can really provide comfort cooling solutions to these multi family projects, mixed use projects, while also not having to compromise on where you put these outdoor units.
So whether you're using a project in the Midwest that's low rise, six, seven stories, but all the outdoor units need to be in a parking garage or an enclosure somewhere off site. You have 500ft of pipe work that you can work on. Let's say it's a taller building, 10 stories and is down in Florida. Well, you could put the units on the roof, go 10 stories down and still have a few, you know, 30 or 40ft to get to the various indoor units and and make sure that you have a viable product without compromising efficiency, runtime and the lifespan of this unit in general.
In addition to that, K through 12 and other parameters offer great opportunities to leverage Linux Real along with our commercial VRF and in addition to that, our industry leading rooftop and residential split units. So in general there's a lot of applications where Linux reel fits well.
But I would like to challenge our engineers to think about if you're putting yourself in the shoes of your customer, the end user of the developer of the potential homeowner down the road, what is the best option for them? Knowing that decarbonization energy efficiency are at the forefront but also what are they going to experience when they're outside in their yard and you have a conventional outdoor unit running 75 decibels which is high efficiency product. Typically where Lennox Real will tap out at 60 and idle around 44, that's equivalent to one of those units in your hotel room. Except this is an outdoor unit so it makes usable spaces more user friendly.
So great question. Thank you very much.
[00:11:57] Speaker A: Thank you very much. This was a great overview. Do you have anything else that you want to say about brf? About single phase heat pumps, about the product at all?
[00:12:07] Speaker B: What I would say is it's available.
It is available for for purchase and for installation.
As always with all things Linux, we would urge you to reach out to our local engineered sales, VRF sales and territory managers. But the simplest means of communication for us is go to Linuxcommercial.com take a look at our website. There are informational areas there where you can find information about the products and also there are information pieces where you can reach out to us. Leave a message and we will reach back out to you. Alternatively, you are welcome to send me an
[email protected].
I'll re reiterate that email. There's actually an additional one. It's VRF Sales.
Thank you very much for the time. I really had a great time having this conversation.
[00:13:02] Speaker A: Yeah, this was great. Thank you so much again for joining us and to our audience. For more information on BRF systems or single phase heat pumps, please visit Consulting Specifying Engineer online at www.csemag.com. again that's www.csemag.com. thank you for listening and we'll talk to you next time. It.
