You don't give your location which is a factor in determining erv/hrv install.
However my question is how do you know that the home
requires make up air?
The first step in my mind is to find out where air
is leaking in the house & duct systems.
Find the leakage sites, seal with correct sealant depending upon where the air is leaking from, seal
all leaks and make house tighter. Then if
fresh air is needed..you'd install your fresh air device.

Houses leak air..when the leaks are sealed then
the air comes from dedicated pathways (duct system)
and can be cleaned, dehumidified and enter the living space to condition it. When the house is leaky,
when hvac system comes on, air is drawn from leakage areas.
Recessed lights, gaps around fireplaces, kneewalls, bath fans all draw fresh air from the attic. Not the best air to be breathing and hell on IAQ.

Blower door test the house, seal leaks, duct test the ducts and return airs and seal with mastics.
The blower door testing will tell you where it leaks,
and at how many air changes per hour your house operates,
and determines whether or not fresh air/ make up air is
needed.

In the case that your house tests at .25 air changes per hour or less, then ERV would be for hot climates, HRV for cold climates.

New construction homes that I have been involved with have tested tight enough to require fresh air. I've never tested an existing home that achieved that degree of tighness, as a lot of detail is involved in the building process.
Existing homes can be made tighter, which in itself will improve IAQ and reduce utility costs.
If I were you I would now put some time and effort into
sealing the house.

Best of luck!

Studies have found that unless you live in an Urban city with smog issues, the typical American home is More polluted than the outside air. Tighter construction has contributed to the containment of pollutants such as cleaners, furniture polish, Floor cleaners, bleaches, window cleaners, adhesives, glues, composit wood glues such as formaldehyde, off gassing of new products such as carpet, and on and on. High humidity as well as plumbing leaks can contribute to mold issues. But tight construction is required for energy efficiency. With proper regulation of outside air, efficiency can be maintained.

An HRV is a simple plate heat exchanger which extracts heat from exhaust air thru the HRV unit. An ERV will recover moisture also. Humidity will transfer to the airstream which is less humid so summertime humidity will be reduced on the outside air. Wintertime humidity will be retained. These units have prefilters but are not able to eliminate pollen. Pollen can be addressed at the furnace with a good pleated fliter rated for pollen removel (3M Filtrete). A Honeywell VisionPro IAQ control system can control all the components.

Breath Clean,

Dan Martyn

Here is a link that might be useful: Broan HRV / ERV

Residentially, you can get an HRV or ERV with built-in HEPA filtration and solve the outdoor air/pollen situation.
These have been around for about 4 years and work well

GSEH3K HEPA Filtration & Energy Recovery
GSHH3K HEPA Filtration & Heat Recovery

Here is a link that might be useful: Broan with HEPA

rock

I recently moved into a new home in N. VA mountains and discovered that I needed both a dehumidifier as well as an ERV. I put the DH in first because we had mositure spots on the basement concrete floors, and that cleared up a funky smell we detected shortly after we moved in. The ERV will go in next. If you have a tight home, you probably need an air exchanger. And in your case, you want one with a HEPA filter.

I was shocked to learn about the pollution problem inside homes - especially new ones. It never occurred to me, but now makes sense, that all of those products used to build your house will be outgassing for quite some time. If those gasses cannot escape, the pollution levels inside the home can be many times greater than the pollution outside.

If you go to the website iaqsource.com and click on the ERV/HRV page it will give you some good info on how the units work, as well as the zones in the country where to use either the ERV or HRV.

I am going with a Broan Whole House ERV which has an integrated HEPA filter as Z mentioned. This unit can handle about 6000 sq feet - more than enough for my entire house.

The only thing I do not like about the Broan unit is that it is designed to run continuously - there is no dry contact closure relay to activate it in conjunction with the HVAC fan. I plan to address this with my own dry contact relay made by RIB, which will be used to provide power to the Broan unit only when when the IAQ contoller calls for the ERV to cycle. When the IAQ contoller calls for the ERV to cycle, you can program it to also turn on the HVAC fan as well. That is how I will get the fresh air input from the EFV to be distributed throughout the basment and first floor - at least those rooms serviced by the main 6 ton heat pump. The other rooms in the house - serviced by 2 other smaller heat pumps will draw this air when they cycle on and off for heating or cooling.

I looked at the Honeywell units which have good ratings and they have dry contact relay ON/OFF so you can tie them to the HVAC fan. However, they are smaller capacity units so I would need 2 ERV's in my basement (one for each heat pump down there) and that would be a pain for me given the location of my second HVAC heat pump. The Honeywell units do not have a HEPA filter which I want, and you probably need.

Good luck.

Thanks, everyone. We're in a hot, humid climate, so an ERV would be better than a HRV.

I am guessing about the need for makeup air because I assume that if we don't open a window when running the high powered range hood over the 6 burner gas range, then air will be pulled through the recessed lights, the four FP chimneys, etc. Given our need to control indoor humidity and keep out pollen, I'd prefer not to do that. We do have good media filters, so if the ERVs are installed before the AprilAire or AccuClean units, the new air will be filtered after the ERV reduces its humidity.

The only way a blower door test will happen here is if we learn how to do one ourselves. I cannot locate anyone in this area who does them. But then, most of the HVAC people (& I've talked to owners & head techs of half a dozen larger companies here) don't know anything about ERV/HRV either. Few have installed two-stage HVAC systems or anything other than minimum code equipment.

Sniffdog, I'm impressed at the capacity of the Broan ERV you mentioned. I don't know if continuous run would be a problem here or not.

We're also weighing the cost/benefit of whole house dehumidifiers to be installed on several of the systems. Right now, I have portable dehus running in three locations, and could use at least three more. The new Soleus dehus are pretty quiet, but it's still a pain to empty them regularly.

The builder of this (spec) house put in 13 SEER single stage equip. that is probably oversized because it short cycles (approx. 10 min. run time) and has difficulty keeping the humidity down. Then there's the issue of the shoulder season when temps don't call for either heating or cooling, but pollen often prevents us from opening windows.

Finally, there's the budget and the economy. Like a lot of others, we're suffering financially and I regret buying this house. Due to a number of issues, both house related and otherwise, we now plan to stay here only until the market recovers. So the goal is to achieve the best IAQ we can with the least outlay. Buyers here will not pay for upgrades to systems such as this, so we will not recoup any of the cost.

rock

The challenge with the Broan for me is that I need to have it connected to the HVAC system so that I can distribute the fresh air around the house, especially on the first floor where we spend 99% of our time. The Broan was designed to operate in a standalone configuration with it's own ducts or just in a basement, even though the manual shows several configurations including one which uses the existing HVAC ducting to distribute air. I am not going to add separate ducting for the ERV - just not going to happen.

I called Broan and talked to a tech about this and he agreed that a dry contact ON/OFF relay would be nice but the design is the way it is. It is very simple to just add an external relay on to the Broan and let the IAQ contoller close dry contacts on the relay to fire it up - while at the same time turning the HVAC fan on. It makes the air distribution to the first floor simple - and that is where I want the fresh air to go first.

You might want to look at the Sante Fe whole house dehumidifier, also on the iaqsource website. I bought one this summer and have it in the basement. It operates in the standalone mode with the humidistat right on the unit. I initially bought the thing just to deal with the basement but found out that when the HVAC fans come on, and they cycle air between the first floor and the basement, so one dehumidifier drys out 2 floors and the air quality is really nice. When you control the inside humidity to a range of 45 to 50% in the summer, you won't need to run the the AC as much. A 78 degree AC setting in my house feels like 76 - thanks to the DH. When I first plugged the DH in, the thing ran for two days straight and sucked out an amazing amount of water.