HRV/ERV systems

[biffnh]

I am having a difficult time finding a designer/installer of HRV and ERV systems for residential applications. I am in central NH. An energy audit on my home shows what I thought - my home is too tight and I need a whole house ventilation system. I use outside combustion air for my oil fired boiler with FHW radiant floor and baseboard heat. I do not have any duct work in place so this complicates it somewhat. Has anyone done this themselves? I have been advised (based on ASHRAE 62.2) that I need 52.8 CFM ventilation rate.

Any ideas would be helpful.

[FloridaOrange]

You may need an mechanical engineer who specializes in residential work unless you have or can find a good full service HVAC contractor.

We only use ERV's in specialized applications and Florida's requirements for treating outside air is different than elsewhere.

[biffnh]

Thanks Matt, yes - I need a HRV unit for up North, but it seems that all the mechanical specialists that deal with anything other than central air conditioning deal only with large buildings. I have researched the units and know just enough to get going, but I don't want to invest $1600 in mechanical equipment without someone helping solve the balance flow between outside and inside, etc. My search continues. The Web has so far been no help and I've made numerous phone calls as well.

[FloridaOrange]

I'll ask my boss on Monday to see if he has any insight. We use(d) Greeheck ERV's but they seem to be more commercial size rooftop units and modules for built up units.

Could there be another solution besides ERV's? Did the report have any other recommendations?

[jadnashua]

A couple of these might work for you. The volume they provide depends on the static pressure of the vents. They should be fairly easy to install.
Panasonic FV-04VE1

[biffnh]

Thanks for the lead on the Panasonic FV-04VE1, I've looked at these along the way, but unfortunately they are not recommended for cold weather use. They ice up and it is during the winter months that I need the HRV - the rest of the year the windows are open! The Panasonic systems are very good and would be ideal if we didn't have December, January, February and March.

[Peter Griffin]

Biff, give Mike Breckon at API of Portsmouth a call. Tell him a NAOSHM member sent you. PM me if you need further instructions.

[biffnh]

Thanks Peter - I'll give this a try. Any lead at this point is welcomed.
Biff

[Stevenc]

I am looking at this for a large condo building and it easier to get this type of information from mechanical companies. Here is a decent resource for residential homes -- www.hvi.org -- http://www.hvi.org/resourcelibrary/publications.html

What I have learned so far -- you are not going to want to duct in your dryer or kitchen exhaust into the HRV system; the dryer lint or kitchen grease really add to your maintenance costs of the system and clog your filters. A good source of air to exhaust to the outside is from each bathroom. The exhaust ducting from the bathroom(s) is easiest to duct into the HRV system. Your may think about an intake duct near the kitchen (not near the stove thou). Your energy audit gave you the information that you need on the CFM rate. Since you are having a difficult time finding a HVAC company in your area, call up one of the HRV manufactures tech support and see if they can help you with the information that you are looking for. Fantech products look like they are primarily geared toward the residential/small commercial HRV systems and may be a good place to study.

Since you will have a constant pull on the bathroom, you will not need to run the exhaust fan as much for showers or other activities in the bathroom. Your house will experience negative pressures when the clothes dryer runs, or the kitchen exhaust/bathroom fans are going. The clothes dryer is the one that has the longest run time each week. Engineering air pressure balances to deal with every possible situation is quite expensive and will far exceed the costs of the HRV unit that you are considering.

Pressure differential reading device -- http://healthandenergy.com/air_pressure_sensors.htm

Hope that helps.

[biffnh]

Thanks Stevenc! The links are great and will provide some help. I have not planned on tying in the dryer - too much of an expense. I plan on tying in the bathrooms - do not have exhaust fans as each bath has a big window and they are open all but in the winter. Thanks again for the links.

[perlfather]

Hi biffnh,
I am in the exact same position, in the middle of building a very tight house in northern NH. How did you solve your HRV problem. Thanks.