HRV "raining" in basement

[Innov8tive1]

I realize that when cool dry air meets warm moist air you are going to have some condensation.
I'm sure it has never been this bad before or maybe we never ran our HRV as much as we have the past few weeks. The temperature dropped last night to around -23°C (-9.4°F) so of course the incoming air was very cold and dry. We were going to bed last night and the wife went into the laundry room and told me there was water all over the place. I went and looked and she was right, there was a LOT of water which had condensed on the ducts from the fresh air side into the house duct work and major puddles on the floor.
I know how an HRV is supposed to work and I realize this is an effect of the way it works but is it normal for it to create so much moisture?

Another complaint I have about an HRV is that it drys the air in the house so much you can feel it. I wake up every morning feeling like I drank heavily the night before because of the dry mouth. Maybe my real complaint is that our house is too tight.........what are your opinions on modern construction and the need for mechanical ventilation?

 

[icefisherman]

I have a 8yr old house that is really tight too. What I do is run the hrv system only when i start to get a inch of ice or moisture on my windows. Seems to help it not get so dry in the house. Of corse the colder it is the more I do have to run it. Otherwise it seems like a waste bringing in cold fresh air, only to heat it up than dump warm air back out, over and over again. If you put your hand by the exhaust side, its amazing how much warm air you are dumping back outside.

 

[cowboyjosh]

my 5 year old house is a little too airtight, even though I believe a house can never be too airtight. When its super cold out like it was yesterday in Colorado (temps never made it to 10 degrees) I get condensation on some of my windows. I don't have a HRV, but its code here to have 2 air intakes into the furnace room, both are 6 inch ducts to the outside, for combustion air. Also its required that the gas fireplaces (mine are Heatilator units) have a fresh air intake, so I therefore have 2 4 inch vents feeding those fireplaces that we never use. What Im getting at is all vents that penetrate the exterior of the house will condensate and in some cases drip, I can see it on the 2 furnace room air intakes in my basement. Some remodelers will wrap those vents in insulation, either spray form or fiberglass. Here in Colorado some of my condensation problem is that we use humidifiers on our furnaces in the winter otherwise you get tagged every time you walk across the carpet and touch a light switch, not to mention its so dry here furniture and hardwood floors will crack and split. I guess it goes without saying that in extreme temps both hot and cold we have to make adjustments to our homes and put up with stupid BS like dripping condensation. I long for the day I can retire to a beach somewhere where the sun always shines and hurricanes or typhoons don't exist.

 

[Innov8tive1]

I long for the day I can retire to a beach somewhere where the sun always shines and hurricanes or typhoons don't exist.

I hear ya on that one...........I think I'm a long way from that dream!

I feel the same way about my HRV, I hate to run it. Not only is it using electricity to run, it's also dumping some of my nice warm air out into the cold making my furnace run more. And for that I am rewarded with dripping ductwork and dry skin.
I am thinking instead of running it so much I will look at putting the plastic film on the windows. Our windows are not bad (double pane sealed units) but they are not up to modern standards either. It is my understanding that even the latest and greatest windows will still have condensation problems. I hate the look of the film, even when heat stretched but it may be my best answer.
I ran the HRV the other day and the humidity in the house dropped to around 30%, I'm sure it would get even lower in mid January. Guess I'll have to drink more water!

 

[HVAC Phil]

Run a 4" duct into return duct from outside, brings fresh air in on cycles. The system you have ***** in the winter. Insulate the 4" pipe coming into the return duct.