Large Tank IN a Basement-Ventilation Suggestoin Please oh brethern of the mamoth tank

To each, their own......

While I don't live on or near the coast anywhere I would think that it would be a common problem in those areas and we'd be hearing from folks saying much the same thing.
 
One could always use the very same set of holes used for the
HRV with a vent fan. Should be easy enough to make the transition.
 
Good point on the vent holes.

How would you plumb existing hvac into a dedicated sealed fish room and when would the vents be open/run considering a powervent unit?

All the time in the summer obviously, but when in the spring/summer/winter?
 
I'd take a 6" supply and return run and tap into the trunk wherever I could for the "plumbing".

Like I said before, the vents being open would be on a day to day basis depending on the weather.
 
Now if I were an old dog I would think that I might be making a puddle on your living room rug. Lucky for you, I'm not!:D
 
first, I stumbled across this thread doing a search on dehumidify.

Capncapo, sense your in the HVAC industry I was hoping you can help me.

I built a small insulated sump box in my garage. I ran my supply & return pipes through the wall to get rid of the sump noise in my living room.

Just after 2 week I have water beading up and running out of my sump box and the wood is just saturated with water. For some dumb reason I never thought about venting out the moisture.

NOW.. My sump box is right next to my HVAC unit in my garage. I have gas heat, and the unit also has a hole house humidifier installed on the return line. I can easily disconnect the humidifier if need be, I really don't need it. Is there a way to connect my HVAC into my sump box to keep it somewhat dry?

Will the gas heat do anything to my tank? or will the humidity do anything harmful to my HVAC system?

My garage is not insulated and my kids keep the garage open most of the time. With that said my garage get very cold in the winter, and very hot in the summer, I really don't want to vent my house heat, or AC out in to uninsulated garage.

Do I have hope or should I just bulldoze the sump box and put the sump back under the tank stand?

Thanks for your time
Dave
 
Hey Cap Quick Question for you. I read this thread but I noticed something odd. In one portion you mentioned this would work with a 90% efficient furnace but in a totally seperate posting you say that a furnace with this rating will do nothing to reduce humidity in your home.

My furnace has an energy star rating of 92.3 so I assume this is its efficiency, which means this mod will do nothing for me. Is this correct or am I missing something? My basement is getting a little damp and this sounded like the perfect fix for me but I'm not sure i can do it now.
 
SOME 90% furnaces get their exhaust air from the inside of the the home while others have an intake that brings fresh air in from outdoors to be used as exhaust air. Some can be set up either way.

If you pull your exhaust air from indoors you will be getting rid of some humidity but I wouldn't rely on it being anywhere near enough to eliminate a problem.

If you have only a single run of PVC going to the outdoors then you're using indoor air for exhaust. Two runs indicate that you're bringing fresh air in to be used as exhaust.

I'd be looking at an HRV if I were you....or at least a vent fan and fresh air intake.
 
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Thanks I Cap Ill have to check that out when I get home. I know I have a single pvc run to vent the exhaust gas but not sure if I have two or not.
 
Ok I never did respond to this but I only have one pvc run going to the furnace and I know that it is the exhaust. So it sounds like I am out of luck on using this mod for my humidity problems. Any one have another suggestion that might work for me? My basement is starting to smell really musty and my tools are rusting so I have to do something soon.
 
You might not want to hear it but the only surefire way is a multi-approach system:

1) Build a fish room. and contain the air. If not treat the whole basement as the fishroom, but its more costly energy wise.

2) Install a ventilator for the basement. This can be a HRV, or simply 2 fantech fans on 6 or 8 inch. One needs to draw air from outside, one needs to exhaust air to the outside. You MUST have Makeup air or bad thigns will happen, trust me. These (or the hrv) run when its cool outside and/or when the realitive humidity outside is less than inside. How these are plumbed into your fishroom basement depends on the setup. In a fishroom, isolate it from your hvac completely. In a basement isolate it, or add it in, choice is yours. The dual fantechs are a poor mans HRV in essence, or are a hrv that doesn't retain the heat which might be preferable in your neck of the woods.

3) In a basement, install a dehumidifier. Install a whole house one if you can, and if your hvac actually pulls air from the basement. The dehumidifier is used in the summer during the day when the relative humidity outside is greater than what you are trying to flush out. In a fishroom you don't have to do this if your room is setup properly and doesn't leak air. You can simply flush air via the fantechs.

4) In a fishroom install a split AC system separate from the HVAC. In the basement you probably wont need this as the dehumidifier can't kick out enough heat if its a portable model, and if its a built in model to your hvac it will kick heat out of your condenser outside. The split AC unit will not be used in a fishroom except to take the air temp down if its interfering with heat buildup in your tank. The fishroom isolates and contains the humid air letting you flush it when you want, at night, ect. The trade off is it can get hot in there during the day, and you might have to cool it. The energy for the slight cooling, if its even needed, is far less than having to run a dehumidifier in a whole basement.

Basically, its haphazard with a basement. You waste alot more energy removing the humidification than in a fishroom because you can't isolate the target humidity and flush it. If you have a tank thats big enough to cause humidity problems in a basement, you really need to build a fishroom, or a canopy over it that is airtight and you can control directly with makeup and exhaust air, or with direct dehumidification. Just installing a dehumidifier only masks the problem and is going to be more $ in the long run if you want to take the basement humidity down an appreciable level from a large tank in a basement.

In summary: fishroom: install makeup and exhaust fan system, install split ac if its needed. Flush humid air when it makes sense for you.

Basement: Install dehumidifier, install fantech/hrv system to cut costs and get cheap dehumidification when able based on outside situation AC normally wouldnt be needed.

Fishroom wins $ wise as far as energy savings go... dehumidifiers eat tons of current.
 
all I have in my tank room is a 6" exhaust fan and an attic style vent allowing fresh air to come in from under my deck. Sometimes humidity gets high because it is humid outside, bit it does work in a pinch for many locations.
 
I agree with wmilas, although I think you can get away with one fan and a vent like Jonathan mentions as long as the fishroom is sealed, because the air will passively enter or exit the vent (depending how you set it up) as the fan does the opposite.

FWIW - I will be using an HRV and mini split A/C in my fish room. I do not want a humidifier because the heat it generates will be an issue in the relatively small fishroom and it will end up driving the A/C to stay on. I also intend to have a chiller located outside the fishroom. I plan to toy around with the chiller and A/C duty cycles to see what works best.
 
<a href=showthread.php?s=&postid=12567269#post12567269 target=_blank>Originally posted</a> by jnarowe
all I have in my tank room is a 6" exhaust fan and an attic style vent allowing fresh air to come in from under my deck. Sometimes humidity gets high because it is humid outside, bit it does work in a pinch for many locations.

Thats an even cheaper version of the fantech, you have makeup air via the vent, and exhaust via the fan. Either way, same idea. I just through the fantech thing out there in case the fishroom isn't on an outside wall, or if its not an outside wall you want to drill through.
 
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