Jeff: Question on an old thread....

[Guest guest]

Jeff, reviewing an old post, at the end of this post you say in cold climates

avoid HRV. Can they be used in summer only in northern states?

I have finally isolated basement air from house but now basement air is very

stale. There is a 'recrack' in cinder block that must be fixed too but it

probably never be a real clean area.

>

> 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

>

[Guest guest]

Barb,

I said to avoid an ERV (which is different from an HRV) because some

of the ERVs had paper heat exchangers (but RenerAire has an ERV that

can exchange moisture and the core is made from plastic, not paper).

But for a basement you oculd still use just an HRV since moisture

exchange is not as important as in the habitable areas.

Keep in mind that you must still have efficient filters outside the units.

Since the last post, I have become aware of a Fantech filter that is

made just for this purpose:

http://www.fantech.net/fb6.pdf

May

May Indoor Air Investigations LLc

Tyngsborough, MA

www.mayindoorair.com

978-648-1055

> JEFF: QUESTION ON AN OLD THREAD....

>

> POSTED BY: \ " BARB1283\ " BARB1283@...

> BARB1283

>

> Thu May 14, 2009 5:20 pm (PDT)

>

> Jeff, reviewing an old post, at the end of this post you say in cold

> climates avoid HRV. Can they be used in summer only in northern

> states?

> I have finally isolated basement air from house but now basement air

> is very stale. There is a 'recrack' in cinder block that must be

> fixed too but it probably never be a real clean area.

>

>

>>

>> 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

>>

[Guest guest]

Jeff, Would the HRV be good way to freshen air in basement? I have to do

laundry down there, and realized also that dryer tosses the freshly cleaned

clothes in to dry.

The Fantech looks great. It's hard to 'make your own things', but I have done

it. Thanks!

>

> Barb,

>

> I said to avoid an ERV (which is different from an HRV) because some

> of the ERVs had paper heat exchangers (but RenerAire has an ERV that

> can exchange moisture and the core is made from plastic, not paper).

>

> But for a basement you oculd still use just an HRV since moisture

> exchange is not as important as in the habitable areas.

>

> Keep in mind that you must still have efficient filters outside the units.

>

> Since the last post, I have become aware of a Fantech filter that is

> made just for this purpose:

>

> http://www.fantech.net/fb6.pdf

>

> May

> May Indoor Air Investigations LLc

> Tyngsborough, MA

> www.mayindoorair.com

> 978-648-1055

>

>