10/22/2014

Zehnder Interview Series: Matt Groves, Technical Sales Engineer

Interviewer:  Could you introduce yourself, Matt?          

Matt Groves:  My name is Matt Groves. I’m the Northwest Technical Sales Engineer for Zehnder America. My territory covers Washington, Oregon, Idaho, Montana, and Western Canada along with Alaska.

Interviewer:  So what do you like most about working with this type of product? HRVs?

Matt Groves: They’re a newer product for a lot of homes and it’s great to be able to educate and help people make the best choice for a healthy and comfortable home.  We design and sell ventilation systems for both new homes and older homes being retrofitted.

Interviewer:  What kind of green trends are you seeing in the HVAC industry?

Matt Groves: Well as people are getting more energy-conscious, the trend has been for tighter, better-insulated homes and with that trend, the ventilation system becomes critical to make them healthy, comfortable and energy efficient.

Interviewer:  How does an HRV/ERV contribute to the energy efficiency of a home?

Matt Groves: If you don’t have an HRV, you would probably be using bath fans.  Bath fans take conditioned air inside the house and exhaust it out without recapturing any of the heat or the cool and then the make-up air enters the house at outdoor conditions through the cracks in the house.  As a much better energy-efficient alternative, HRVs are constantly recapturing most of the energy of the conditioned air, either heat in the winter or cool in the summer and high-efficiency models are recapturing around 90% of this energy.  For example in the winter, if the outside temperature is about 30° F and your indoor temperature is about 70° F, the HRV will bring that fresh air in from the 30s and warm it up to within a couple of degrees of room temperature just by transferring that recaptured heat energy to the supply fresh air stream.

Interviewer:  What the difference between an HRV and an ERV?

Matt Groves: The simple answer is that the HRV only transfers heat while the ERV transfers both heat and humidity.  A little more technical answer is the HRV is only transferring the sensible heat, where the ERV is transferring both the sensible and latent.

Interviewer: How important is it to have your HRV system professionally designed? Versus just purchasing the unit?

Matt Groves:  You need to size the HRV system properly to know it’s going to run the most efficiently. Improper sizing can waste a lot of energy and might cause the system to not be as efficient at the flow rate you need, so those are the most important reasons. As far as the ductwork, you need it sized properly so you get the correct flow rate to each room and the system can be properly balanced.

Interviewer:  Why is it important to have the system commissioned after the installation?

Matt Groves: The commissioning is a critical step. It ensures that the correct air supply and exhaust air flow rates meet the design requirements and also makes sure the HRV system is operating at its most efficient setting.

Interviewer: Would you say that the Zehnder system is easy to install?

Matt Groves: Yes the entire system is very easy to install. We have a lot of first-time users installing it themselves.  We do the design for them and mark locations where we recommend registers go.  They’ll install the registers, install the HRV and distribution boxes and then just run our tubing to connect each register to the distribution boxes.

Instead of having to deal with cutting sheet metal and using messy mastic sealant, you can cut our tubing with a utility knife and the connections are sealed with o-rings.  To make a connection, just install the o-ring onto the tubing, slide the tubing into the fitting and then install the clip.  Then you have an airtight connection.  It’s very simple to run throughout the house. The tubing is just less than 3 inches OD, so you can use a 3-inch hole saw in 2×4 walls with it, while with regular ducting you might not be able to do that.

Interviewer:  What kind of support does Zehnder offer?

Matt Groves:   We offer a free basic design for residential projects which includes the recommended flow rates, system components and a general layout of register locations.  For non-residential projects, we’ll work with their mechanical engineer or HVAC professional to determine the best system to meet the design requirements.  The process can be started by the customer sending us the pdf of a floor plan and answering general information on our online quote request.  If first time installers have installation questions, we have great online tools and installation videos that they can also watch and we’re also available to answer questions that they might have.

Interviewer:  What kind of maintenance is involved with the HRV system?

Matt Groves: The most important maintenance is to change the filters.  We have a reminder icon that comes on to the controller every few months to remind people to check filters, but it’s very important to check the filters on average every 3-6 months and replace as needed.

Interviewer: What are your top one or two tips that you would give specifiers when they are choosing an HRV or ERV system? Not just Zehnder, but what tips in general when people are looking to pick an HRV system?

Matt Groves:  Definitely talk to the manufacturer and the manufacturer’s reps and find out what systems works best for their application. We have the spec sheets online to look at but take advantage of our design service so you can be confident it’s designed by somebody who knows the systems and can design the best one for you.

Another great resource for comparing the performance of different brands and models is the Heating and Ventilation Institute’s website (HVI.org) which has a list showing the efficiencies and energy use of many of the HRVs and ERVs sold in North America.

Interviewer: Great, thanks Matt, that’s all the questions I have. Thanks for your time and expertise.

Matt Groves:   Thank you as well.