Re: The smallest Heat Recovery Ventilators for apartment dwellers

[Guest guest]

Live,

Although an HRV can make a dramatic improvement in the IAQ by

removing stale air and bringing in fresh air, these devices have a

big potential for mold growth. In fact, every unit I have seen, with

one exception, was full of mold.

Unfortunately, few if any of the HRV manufacturers supply their

equipment with adequate filtration. These devices run 24/7 and suck

in pollen, bugs and spores from outdoors and lots of housedust from

indoors. High huumidity is all that is needed to start the brew.

How do you avoid mold problems? If you plan to add an HRV, throw away

the useless filters that most manufacturers supply. Then, outside the

HRV equipment, in-line in the ducts, install holders for at least a

four-inch thick pleated media filter (minimum MERV 8 rating, about

20 " x 20 " inches, such as an Air Bear), one filter for the fresh air

intake and one for the house air intake. Make sure that the interior

of the HRV unit has no exposed fibrous insulation (you want a smooth

finish to wipe down) and that there is a drain for any condensate

that might form.

The heat exchange core must be cleaned regularly (several times a

year) as well. Only get the type of HRV with an easily accessed core.

If the HRV comes with a MERV-8 filter and it is airtight, it should

be fine as is. In cold climates, avoid the ERV.

Jeff

www.mayindoorair.com

--- In , LiveSimply <quackadillian@...>

wrote:

>

> Looking for the smallest, most economical HRVs, I found a very small

> one from Panasonic that sells for around $325 on ebay..

>

> http://www2.panasonic.com/consumer-electronics/shop/Building-

Products/Ventilation-Systems/model.FV-04VE1_11002_7000000000000005702

>

> Fantech makes some very small units, that work with 4 " ducting..

Cost

> is around $400-ish

>

> http://www.fantech.net/hrv_erv.htm

>

[Guest guest]

Wow. Good to know.

I am learning so much for the house I will eventually get, by hook or

crook!

[Guest guest]

Jeff,

THANK YOU for this advice.. Yes, this sounds like t makes sense.

I have the kind with the removable core, and easily cleanable..(the

links for the ones posted also have removable cores)

and I have been filtering the intakes, but I think I am going to redo

it as you say..with two larger surface area filters..

Thanks again..

[Guest guest]

I think Thermastor makes an air exchanger with tight filter on it, but

I think it is only on the air intake side and you can get as high as a

hepa. However it is a couple thousand installed. UltraAire

>

> HRV equipment, in-line in the ducts, install holders for at least a

> four-inch thick pleated media filter (minimum MERV 8 rating, about

> 20 " x 20 " inches, such as an Air Bear), one filter for the fresh air

> intake and one for the house air intake.

[Guest guest]

Jeff,

I have to confess, I'm being lazy, I could probably find this out on

my own.. but - since it sounds like you know this subject, do you have

any recommendations for filter holders? 20 x 20 seems as if its the

most common size (I'd like to be able to use different brand filters)

and for a long time I've been meaning to build a filter box for my HRV

intake, but if there are any prefab solutions that offer the ability

to use different filter *depths* that would be great. It doesn't seem

like a tall order, I cant see any reason why adjustibility would be

hard to engineer.

This is for an HRV, on the outdoor intake side..cold winter (zone 5) I

don't have major pollen issues, but I do have mold issues..

Air Bear looks like a brand of filter.. they are exceptionally good?

(or you wouldn't have mentioned them..)

I have an aluminum core unit, so washability isn't an issue at all,

its easy.. also all my ducts and registers are easy to clean too..

(built with cleanouts out of plastic pipe, also I have a homebrew duct

cleaning brush)

Thank you!

I agree with what you said about HRV vs. ERV. I figure that I can

always add humidity if I need to, I would rather not have a

" cardboard " (as somebody I spoke to while i was looking for my HRV put

it) or even Goretex enthalpic core, it sounds like a potential trouble

spot bigtime..

All in all, we are really happy we got the HRV. It basically makes the

ventilation thing just work, without our having to think about it..