We recently had an energy audit done by Mass Save. They found that our house is reasonably tight and to improve air quality, recommended either a bath fan running full time, or an ERV.
We're in SE Massachusetts, heat is hydronic hot water by natural gas. Solar on the roof, with excess available to run fans fulltime...
I don't think the bath fan is a good idea - it will exhaust warm air in the winter and negatively affect the draft for both my boiler and wood stove insert.
So, I'm planning on having an ERV installed. I may get as much as $750 back from Mass Save for doing so...
I need some advice on where to install the unit. The house is a traditional colonial, with attic access over the upstairs bedrooms, and a cathedral ceiling den off the kitchen on the first floor, where the wood stove insert is going.
Initially, I was going to go with a Panasonic ERV bath fan replacement in the master, but I'm thinking that I'd prefer to exhaust that humidity to the outside.
Instead, I'm thinking about a (non-bath) unit that will require 4" or 5" vents in two separate locations. Potentially:
They're in the range of $500-750 and the larger Broan has the correct CFM for my house (90). The smaller one is just a bit short, as is the Fantech... I am leaning toward the Fantech as it looks like a more robust unit.
For these units, I have some flexibility in where I can install them and run the vents. I can run vents through two bedrooms upstairs, or I can run one vent upstairs and the other into the den, (close physically but half a house away with regard to air flow). The den is where our Kodiak insert will be installed.
[edit] Installation instructions for these units state that they must be in "conditioned" space, not an unheated attic. Uh oh... The only place that conceivably works is the garage, and that gets below 54 degrees in the winter too. I'm also taking another look at the boiler room (below the den)...I'd have to go up through the garage and may have to cut too much in the way of framing to get through to it.... If I can install the unit in the boiler room, the return vent would go to the den on the first floor, and the (inside) exhaust vent would go to a ceiling in the second floor (above the garage).
We also have a full finished basement, but it's somewhat isolated (no good access to run vents to/from it.)
Is it better to have the two house vents widely separated? On different floors? If I run them on different floors, do I want to work with the airflow -- push the cooler air into the first floor and pull the warmer air from the second floor?
I appreciate your feedback and any BTDTs. Any thoughts on the Broan versus Fantech brands?
Thanks!
We're in SE Massachusetts, heat is hydronic hot water by natural gas. Solar on the roof, with excess available to run fans fulltime...
I don't think the bath fan is a good idea - it will exhaust warm air in the winter and negatively affect the draft for both my boiler and wood stove insert.
So, I'm planning on having an ERV installed. I may get as much as $750 back from Mass Save for doing so...
I need some advice on where to install the unit. The house is a traditional colonial, with attic access over the upstairs bedrooms, and a cathedral ceiling den off the kitchen on the first floor, where the wood stove insert is going.
Initially, I was going to go with a Panasonic ERV bath fan replacement in the master, but I'm thinking that I'd prefer to exhaust that humidity to the outside.
Instead, I'm thinking about a (non-bath) unit that will require 4" or 5" vents in two separate locations. Potentially:
- Broan HRV70Se
- Broan HRV90HS
- Fantech VHR 704
They're in the range of $500-750 and the larger Broan has the correct CFM for my house (90). The smaller one is just a bit short, as is the Fantech... I am leaning toward the Fantech as it looks like a more robust unit.
For these units, I have some flexibility in where I can install them and run the vents. I can run vents through two bedrooms upstairs, or I can run one vent upstairs and the other into the den, (close physically but half a house away with regard to air flow). The den is where our Kodiak insert will be installed.
[edit] Installation instructions for these units state that they must be in "conditioned" space, not an unheated attic. Uh oh... The only place that conceivably works is the garage, and that gets below 54 degrees in the winter too. I'm also taking another look at the boiler room (below the den)...I'd have to go up through the garage and may have to cut too much in the way of framing to get through to it.... If I can install the unit in the boiler room, the return vent would go to the den on the first floor, and the (inside) exhaust vent would go to a ceiling in the second floor (above the garage).
We also have a full finished basement, but it's somewhat isolated (no good access to run vents to/from it.)
Is it better to have the two house vents widely separated? On different floors? If I run them on different floors, do I want to work with the airflow -- push the cooler air into the first floor and pull the warmer air from the second floor?
I appreciate your feedback and any BTDTs. Any thoughts on the Broan versus Fantech brands?
Thanks!
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