Zehnder Comfosystems: Your Fresh Air Maker

Often when you are building or remodeling a home, the subject of air-quality or ventilation isn’t a topic that comes up. However, adequate ventilation, or preferably optimal ventilation, is increasingly important for a number of reasons. First, homes are becoming increasingly air-tight to meet new building standards and without a ventilation plan the result can be homes that are air-tight but uncomfortable, and possibly unhealthy to live in. Second, the increasing number of pollutants both inside and outside home make it increasingly vital to provide continuous fresh air for health and comfort. In addition, ventilating your home with a Zehnder Comfosystem provides energy savings. Zehnder HRV and ERV systems bring fresh air into your home 24 hours a day while removing stale air. Conditioned home air temperature loss is minimal as plates extract the energy from the air leaving your home and is transferred to the fresh air coming in. Watch the video above to learn more about how Zehnder’s system works to keep your home clean and comfortable. The information below explains other reaosnsy why a Zehnder HRV or ER is a good investment for your home.

Zender Heat Recovery Ventilation (HRV) Systems Promote Health, Comfort and Hygiene

On average, we spend approximately 70% of our time inside, therefore the provision of a comfortable environment is very important to both our health and our sense of well-being.  Fresh air promotes well-being and a healthy lifestyle. Poor indoor air quality can lead to a rise in asthma and allergic symptoms due to the increased concentration of allergens such as dust mites, VOCs, pollen, and mold. With optional fine filters which capture fine dust and pollen, even allergy sufferers can breathe easily.

Zehnder Comfosystems products provide good air quality through continuous extraction of moist, stale air from bathrooms and kitchens and a continuous supply of clean, tempered air to habitable rooms. Low-velocity air supply ensures that fresh, clean air does not create drafts around the home.

Zehnder HRV Systems Provide Energy Savings

Zehnder Comfosystems products use recovered and renewable energy sources to heat and ventilate our increasingly airtight properties in an energy efficient and environmentally friendly manner. Cross-flow, counter-current heat exchangers are standard equipment for Zehnder ventilation systems. They are therefore capable of transferring the heat energy of the used air to the fresh air. This heat transfer takes place through thin plastic plates according to the counter-current principle. Whole house heat recovery ventilation technology can recover up to 90% of the heat and contribute to an energy savings of up to 50%.

Zehnder HRV and ERV Systems Helps your Home Retain its Value

The installation of a Zehnder Comfosystems product offers a tangible investment in the future value of your home. Our products will help prevent degradation of the fabric of the building from mold and mildew formation as well as reducing heating and ventilation costs. Our forward-thinking technologies will ensure that the property is upgraded to tomorrow’s standards, today.  Zehnder Comofosystems provide protection against mildew and protection of the building against moisture damage caused by a lack of ventilation.

Zehnder HRV and ERV Systems are Easy to Install

Because Zehnder design and manufacture all the elements of their systems, the coordinated system components are designed to fit together. This integrated functionality allows for a more rapid system installation saving both time and money for both the installer and the end user.

Want to learn more about Zehnder HRV systems? You can use the contact form to the right or peruse some of the information and resources below.

Zehnder Frequently Asked Questions

Below is a quick guide to some of the more common questions asked about Zehnder products. For more information, please reference other Zehnder documents on our website or contact us directly at 1-855-367-7442

+ What size Zehnder unit do I need for my home?

The basic ventilation rate formula under ASHRAE 62.2 recommends 7.5 CFM per person in the home plus 3 CFM for every 100 sq ft of enclosed building area. Passive Houses have different requirements, however. The best way to ensure an accurate sizing is to request a quote on Zehnder’s website. You can find the link to that page here

+ What’s the difference between an HRV or an ERV?

Both the HRV (Heat Recovery Ventilator) and the ERV (Enthalpy Recovery Ventilator) provide continuous ventilation needed in today’s airtight homes. HRVs utilize a heat-exchanger core that captures the heat from outgoing stale air and applies it to incoming fresh air. The ERV core is made from advanced materials that allow not only heat but also moisture from outgoing air to diffuse into the fresh incoming air. This is especially important in cold climates when the ambient outside air temperature is below freezing and the relative humidity is at or near zero.

+ Is the ducting UL listed?

The ComfoTube ducting is not UL listed, however the ComfoFlex ducting is. Be sure to check in with local building code to see what is required in your area.

+ What are the electrical requirements?

All of the Zehnder HRV’s require a 2280/230 V, 50-60Hz connection with a dedicated 15-amp breaker.

We supply a stainless exterior wall grill for use with Zehnder’s ComfoPipe insulated exterior ducting. Intake and exhaust locations should be at least ten feet apart in order to avoid cross contamination, and if either exterior duct run is longer than 15 feet, you’ll need to upsize your duct’s inner diameter by an inch.

+ Do I need to insulate my exterior duct runs?

Yes, your exterior duct runs must be insulated with an air permeable to R5 or better to prevent cold intake air from causing condensation to form on the duct. We recommend Zehnder’s ComfoPipe, which is already insulated, airtight and very simple to install.

+ Do I need to insulate my interior duct runs?

Interior duct runs should only be made within the conditioned envelope of the building. Avoid routes through exterior walls, unconditioned spaces, and spaces that are under insulated.

+ How do I balance the system after installation?

In order to qualify for Zehnder’s warranty, you’ll need to have your system commissioned by a certified commissioning agent. You can start the process by submitting your request on Zehnder’s website and completing their pre-commissioning checklist, after which a representative from Small Planet Supply will reach out regarding payment and scheduling. You can find Zehnder’s webpage here.

+ How do I prevent my HRV/ERV core from freezing during the cold winter months?

It is important to have adequate frost prevention and depending on your climate, there are best practices available. Option One – Utilize a ground source Pre-Heater/Pre-Cooler. The Zehnder ComfoFond-L utilizes a ground loop of glycol and a small circulating pump to pre-heat or pre-cool and dehumidify incoming air with a hydronic coil. Option Two – Utilize an electric or hydronic pre-heater. By warming the incoming air prior to entry into the H/ERV, frost is prevented. Option Three – Imbalance flows to allow for warm exhaust air to defrost unit. This option either slows or stops the incoming, cold air while allowing the exhaust air to warm the Heat Exchanger’s surfaces and remove frost.

+ What is summer bypass and how does it work?

During summer nights and in the shoulder seasons of spring and fall with strong sunshine, the house can become too warm, while the outside temperature remains pleasantly cool. In such cases, heat removal by what is known as “free cooling” helps: the Zehnder ComfoAir units are equipped with a standard automatic bypass for just this purpose, and diverts 100% of the relatively warm extract air from the heat exchanger, introducing cool supply air to the space.

+ If I install a Zehnder, do I need to have bathroom and laundry rooms fans, a kitchen range hood, etc.?

If return diffusers are installed in the bathrooms or laundry rooms, you will not need an extract air fan as the HRV will effectively replace them. A kitchen range hood will still be required, however except in Passive House designs by a certified Passive House Consultant.

+ Do I need a condensate drain for my Zehnder?

You will need a condensate drain, which Zehnder provides in the form of a waterless p-trap, which will need to be connected to the home’s drainage/sewer system as per code. This is required for all HRV systems. The ERV systems do not require a condensate drain as they recirculate the moisture that passes through them.

+ What kind of maintenance is required for these HRVs?

Maintenance of the Zehnder HRV’s is limited to periodic cleaning or replacement of the filters accessible from the front of the unit. The exchanger core should be inspected and cleaned annually (depending on the outside air quality). Please see the unit manual for additional servicing tasks.

+ What is Zehnder’s Warranty policy?

When installed according to the applicable Zehnder America, Inc. Installation instructions and the applicable local, state, and federal building codes and unless specified otherwise, all Zehnder America, Inc. products sold in North America carry a two (2) year LIMITED WARRANTY (from the original date of shipment by Zehnder America, Inc.) covering defects in the original manufacturer. For a full warranty policy, please visit Zehnder America’s website at ZehnderAmerica.com.

Zehnder Information Request Form

Have Zehnder questions or want more information about Zehnder? You can call Small Planet Supply at 1-855-367-7442 or use this form to request additional information. *
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Additional resource pages

Learn more at a workshop -  See if there are any upcoming workshops.

Education - What is an HRV , why you should have one, and how to maintain it.

Request a system quote - See the description in the sidebar for more info on full system quotes.

Installation - How to install your Zehnder HRV.

Commissioning - Making sure your Zehnder HRV is set up properly.

Learn more about our network of advisors and installers.

See the Zehnder product list. Most items in stock for immediate delivery.