9/4/2014

Zehnder Interview Series: Kevin Rapp, Technical Sales Representative

Interviewer:  Could you introduce yourself, Kevin?

Kevin Rapp:  My name is Kevin Rapp. I’m the Midwest Technical Sales Representative for Zehnder America, which includes most of the central United States.

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

Kevin Rapp: I’m seeing an increased adoption of centralized ventilating systems instead of either an exhaust-only system or a partnered ventilation system with the central heating and air system.

Interviewer: How does an HRV or ERV help with the home’s indoor air quality?

Kevin Rapp: With a commonly used exhaust-only system using bath fans for the most part, air is just being pulled out of the house. Most bath exhaust fans are in the 50 cfm range.  What that means is to make up for that air exhausting the home,  50 cfm of outside air is coming in from somewhere. With that air coming in, often the best case scenario is that it’s coming in around your doors or windows.   This means you’re still bringing in any pollutants from outside including allergens as well as heat and humidity or cold temperatures. More than likely the incoming outside air is coming down walls, from attic crawl spaces and other undesirable places.  With a balanced HRV system like ours, you are able to control the fresh air coming in and filter it before it goes into the living spaces.

Interviewer: How does the Zehnder HRV system help allergy sufferers?

Kevin Rapp: A lot of it goes back to the previous question. With our system being balanced and dedicated, we know that we are bringing in an equal amount of air where it’ll be filtered before it comes into the house. The other part is we’re putting it where it needs to be, being in the bedrooms and the living spaces.  With an exhaust-only type of system or a system that’s coupled with the HVAC system, you don’t know where that fresh air is being put and if it’s put in areas the inhabitants will mostly be.

Interviewer: What are some of the advantages of a HRV/ERV system over an exhaust-only system in an energy-efficient home?

Kevin Rapp: Well you have significant energy savings because with an HRV or ERV, you are recovering the energy in the room temperature air.  With an exhaust-only system, if it’s thirty degrees outside, you’re bringing in thirty degree air to make up for what you’re exhausting out.  You have to reheat that thirty degree air up to the indoor room temperature, probably sixty-eight degrees. With an HRV/ERV system, particularly ours in that same scenario you’d be bringing that fresh air back in somewhere around sixty-five or sixty-six degrees so now you’re only having to reheat that air two or three degrees and that’s an awfully big energy savings. It’s also a big comfort savings because your home is not going to be drafty.  Through the HRV/ERV, the air is coming in near room temperature.

Interviewer: Should the HRV system be separate from the HVAC system?

Kevin Rapp: Yes it should.  The two biggest reasons are efficiency and an HRV is most effective when it’s properly balanced.

Interviewer: Thanks Kevin. What makes Zehnder’s HRV system so quiet?

Kevin Rapp: Not only are the units properly designed for maximum quietness but it’s also part of the proper design parameter.  The proper design of the system and proper system selection is critical in maintaining quiet operation.  This is why Zehnder designs all of the systems- so you have the correct unit and air distribution components for maximum quietness.

Interviewer: What are your top one or two tips that you would give to consumers when they’re choosing an HRV or ERV system?

Kevin Rapp: My number one recommendation to anyone I speak to selecting an HRV is to do your research. HVI.org is a great resource.  HVI provides a good comparison between units since all units are tested under the same protocol. I would also recommend choosing a manufacturer that can help you engineer the whole system- HRV and air distribution components.  If you buy just the HRV box, you don’t really know what you will get as far as efficiency until it’s installed because the air distribution components in those cases aren’t particularly matched for the system.

Interviewer: Great, that’s all the questions I have for you. Thanks for your time Kevin.

Kevin Rapp: Alright, thank you very much.