Fellow Electrical engineer needs guidance to learn about residential basement ventilation

[MiniMe4Eng]

Hi guys

I am an electrical (Electronics in fact) engineer and I am trying to educate myself in regards to how to ventilate a residential basement
I don't necesarly want to waste your time with this but I would appreciate and advice. Instead I would like to ask you to recommend me some books, web pages or any kind of documentation where I quickly read about how to deal with this

Here is my problem just in case you would have the time and you are in the mood to answer a problem that is not really int the engineering domain:
I am trying to understand what is the proper way to ventilate a basement. I have a finished basement which if not ventilated starts to smell ..like a basement and I don't like it.
If I run the AC fan continuously the problem diminishes but I get a slight smell upstairs (a raised bungallow, above the grade windows for basement)
What are the recommendations for properly ventilating the basement? The basement has an apartment with a kitchen and a bathroom that have their own ventilators. On top of that I have the chimney for the old furnace. I am thinking about using any of these to evacuate the smelly air and I hope that better air will be sucked from upstairs .... will this work?


I hope I posted this in the right section, if not please let me know where should I post it
Any help will be much appreciated

 

[chicopee]

I would first run a dehumidifier before thinking about "HVACing" a basement. If you are a degree Electrical Engineer, then you have the capacity to read technical books, so get a Mark Eng. Handbook, Chem Eng. Hdbk or Kent"Power" Hdbk. as they have excellent sections on HVAC.

 

[Strong]

Did you Google:
how to ventilate a residential basement

Lot of stuff there.
Walt

 

[MiniMe4Eng]

With using a DH I got the humidity under control, stabile at around 45% RH at 19-20C
So that was taken care of but the slight smell is still there
I did google that and that is the very problem that I am trying to avoid. I need some directions in order to be a little more efficient at reading what matters.
Google will return a lot of garbage and marketing mixed with valuable information That is the major problem we have today in any field. The info we have to sort and digest is just too much

 

[SAK9]

http://www.rewci.com/xchanger-basement-fan.html

 

[MiniMe4Eng]

thank you guys for all your answers !
Someone recommended me a Heat Recovery Ventilator. Is that an overkill?
The other question that I have is this, Can I send the air up through a the chimney the was used by the old non condensing furnace ? (not is use anymore)

 

[DBronson]

MiniMe4Eng:

You might want to explore Joe Lstiburek's website. Tons of good info all with solid engineering & no ads.

Link

Regards,

DB

 

[MiniMe4Eng]

Can I use the chimney to evacuate the bad air?
I was told that I might need a special/better fan to push the air through the chimney.... is this true?
For the intake, the furnace already has an air intake pipe. If I force air out through the chimney, will the air get in through the furnace air intake due to differential pressure between inside and outside?

 

[willard3]

Hire an Engineer who knows how to do this and stop looking for free engineering here.

 

[LittleInch]

The base issue is probably that somewhere you have a damp issue creating the typical musty smell. You need to sort that first before trying to ventilate your way out of the problem. Do a full damp check on the walls and find the area(s) you need to fix.

A chimney isn't a bad idea for exhaust, but a standard ventilation fan you buy at the hardware store won't have enough punch to flow much air up a long chimney. If you look carefully at the details, they are only good for 2-3m of outlet duct. You will also need to seal it very well or else you're just going round in circles.

If you evacuate air from a room it will be replaced by air from elsewhere. However this could be from a variety of sources. it is difficult to flow air in from the outside to a basement without helping it a bit.

A heat recovery ventilator is a good idea, but only if you have a big basement and you need a lot of heating.

With a kitchen and a bathroom you're generating a lot of humidity and even with their own ventilation system, some will escape into the rest of the room and as said before, unless the ventilation fan is sized for a longer exhaust duct, it won't be shifting the recommended number of air changes per hour Kitchens are noted as 15 to 60 per hour(!) and Cellars or basements 3 to 10.

Think about air flow from fresh air in past the humidity generating think to the vent inlet. Are they positioned right?

I would try some vendor websites like this

http://www.vent-axia.com/files/Ventilation Design Guidelines 2.pdf

Of course a professional engineer would help, but if you can fix the damp walls first then try the other avenues.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MiniMe4Eng]

Thanks a lot, really useful.Fixing the damp walls is going to be a challenge, the basement is finished and I can not just tear down all of them to find where is the problem.

 

[LittleInch]

You shouldn't need to tear then all down, but do some checking using a moisture meter.

Basements are notorious for damp issues so I'm a little surprised that this wasn't a key design and construction issue in the recent work.

As said, you can't solve damp issues with ventilation, only reduce it. Inputting humidity sources is not a great idea either.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MiniMe4Eng]

I already have a moisture meter but it does not show anything suspicious
I used this one:

http://www.canadiantire.ca/en/pdp/t...al-moisture-reader-0574553p.html#.V0LsAPkrLcs

HOw do you suggest I should use it in a finished basement that has insulation behind the walls?

 

[LittleInch]

Oh,that will make it difficult. were the walls tested before you added insulation?

Anyway, you will need to up scale your ventilation system I think to cope with longer ducting and also allow maybe more air changes than before. You will probably need pretty continuous forced ventilation though.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MiniMe4Eng]

I bought the house like that, I did not do the reno.

 

[MiniMe4Eng]

I must admit that I am really confused.
In my opinion odor means humidity.
My humidity levels in basement are 45-47 right now
The DH is struggling to squeeze more from that. It worked pretty well when the humidity was higher.
Does the efficiency of these things go down with the humidity level?
It seems to need extended periods to run to bring the humidity level one or two percent down.

I use this guy

https://www.danby.com/products/home-comfort/ddr60b3wp/

Basement space is under 1000 sqf
Temperature around 19-20
RH 45-47%

The DH has a build in hygrometer and it goes up and down quite visibly ..not sure why
When it starts automatically let's say it is set at 40% and it kicks is at 47% I see it going down and then back, up...sometimes above the initial kick in temperature. Before I call technical support I wanted to know if this is expected since the DH is releasing warmer air back to the basement.

 

[MiniMe4Eng]

Hmm I think that I found my problem

I have a water pump similar with this one

I am talking bout what is marked with #3 in the picture.
In my case that pipe goes to the ceiling ..partially open in the furnace room and from there through the finished ceiling it traverses a hallway and I am not sure if it joins the drain of my bathroom downstairs or the drain of my sink or bathube upstairs, they are all represented in the picture.

I need to verify the integrity of this plastic tube (it is plastic tube as far as I can see, till it enters the wall toward the hallway). How can I do it?

Here is what made me think about this.
On the top floor (ground level) at the entrance in the bathroom the baseboard is made of something like MDF.
This is at the right side of the bathroom door. In the picture I figured the pipe as I initially thought it would go.

During the last two summers that piece was humid in one corner, close to the door, exactly in the spot that I am talking about above.
This winter and till a yesterday when I started the AC that piece of baseboard was dry. I have been checking it regularly.
Now I can feel it again, it is humid. If I stick the humidity meter into it it shows 25% at floor level and 20% a half of an inch higher.
I can't really understand what is going on. I tested the drywall just above that patch and it is dry, it barely moves the humidity meter form the zero position.

 

[chicopee]

Since now that you have brought up the subject of bathrooms, make sure that vents are provided for all sinks, toilets, bathtubs and sumps if any. Lack of proper venting for the items mentioned can make life intolerable.

 

[chicopee]

One more item would be a vent at the trap connection for washing machines.

 

[MiniMe4Eng]

I just checked them, they are all where they have to be