Fish Room HVAC/Humidity options

[Justfebreezeit]

Sight unseen I would address the house problem this way.

Add a unit upstairs and duct it into the existing duct (disconnect the upstairs ductwork from the downstairs)

If the garage isn't used for cars, I would add a drop and return in the garage from the downstairs unit to take care of that.

All this depends on the garage not housing cars. Here in soflo (and i'm sure most places) its illegal for us to recommend and install duc work that connects the house to the garage. Carbon monoxide poisoning being the main issue.

There is really so many options and its fun to tinker and hear other peoples ideas. Good luck!

 

[FarmerTy]

Sight unseen I would address the house problem this way.

Add a unit upstairs and duct it into the existing duct (disconnect the upstairs ductwork from the downstairs)

If the garage isn't used for cars, I would add a drop and return in the garage from the downstairs unit to take care of that.

All this depends on the garage not housing cars. Here in soflo (and i'm sure most places) its illegal for us to recommend and install duc work that connects the house to the garage. Carbon monoxide poisoning being the main issue.

There is really so many options and its fun to tinker and hear other peoples ideas. Good luck!

Wow! Above and beyond JFBI! Thanks for taking the time to respond!

So you're saying add an additional unit for the upstairs but use the existing ducting. Would they just disconnect it from the box and build another distribution box for the upstairs ducts?

Would there be any issues with the bottom unit now being greatly oversized for just the bottom floor? I guess adding the 200 sq ft of the fish room will use up some more of its capacity and I'll honestly not plan to add a return on the fish room and just vent the room out of the house so it can take the heat and humidity with it.

That sounds like a great solution without having to use mini-splits, portable AC units, or window units.

 

[Justfebreezeit]

Wow! Above and beyond JFBI! Thanks for taking the time to respond!

So you're saying add an additional unit for the upstairs but use the existing ducting. Would they just disconnect it from the box and build another distribution box for the upstairs ducts?

Would there be any issues with the bottom unit now being greatly oversized for just the bottom floor? I guess adding the 200 sq ft of the fish room will use up some more of its capacity and I'll honestly not plan to add a return on the fish room and just vent the room out of the house so it can take the heat and humidity with it.

That sounds like a great solution without having to use mini-splits, portable AC units, or window units.

It really just depends on how over sized it ends up being. How many sqft does it also cool upstairs? downstars? and if you know the tonnage of the unit?

If its over sized a little it shouldn't be a problem, but if it ends up being well over sized you will run into humidity problems as the unit will run less and therefore dehumidify less as well.

If you run into the humidity problem you can look into swapping the unit for a smaller tonnage down the road.

 

[lion king]

Thanks Lion King! I'm amazed at the great advice I'm getting on here and extremely greatful for everyone's responses.

I'm not really sure what a package unit is. Is that just a supplemental unit added to your existing one that uses the existing ducts?

A package unit just means a unit that has the cooling and air handling together in one package. The main point my ac guy advised me of was that the drainage part of the mini splits are their Achilles heel. Each mini split head is fed a cooling line and a drainage line, that drainage seems to need regular maintenance. He advised primarily I should mount the heads on an outside wall, that when mounted on an inside wall they use a pump to facilitate the drainage. As you can expect, this proves to be a point of maintenance and failure. He said his company was already fielding many calls from mini split clients, from clients that didn't use them for installation. There's also apparently a shortage of qualified and knowledgeable technicians to handle the installation and maintenance.

 

[FarmerTy]

It really just depends on how over sized it ends up being. How many sqft does it also cool upstairs? downstars? and if you know the tonnage of the unit?

If its over sized a little it shouldn't be a problem, but if it ends up being well over sized you will run into humidity problems as the unit will run less and therefore dehumidify less as well.

If you run into the humidity problem you can look into swapping the unit for a smaller tonnage down the road.

4 ton unit on 2300 sq ft. Split about 1300 downstairs, 1000 upstairs. I think it'll be well oversized for just cooling 1300 sq ft if I'm adding another unit to cool the upstairs, right?

Maybe a dumb question but for swapping to a smaller unit, will companies be willing to do it for free if they are getting a 2 year old unit that's pretty new in the swap? Should I just sell the 4 ton unit myself if I won't get much credit back from them on it? Be a shame to get no value back for such a new unit.

 

[FarmerTy]

A package unit just means a unit that has the cooling and air handling together in one package. The main point my ac guy advised me of was that the drainage part of the mini splits are their Achilles heel. Each mini split head is fed a cooling line and a drainage line, that drainage seems to need regular maintenance. He advised primarily I should mount the heads on an outside wall, that when mounted on an inside wall they use a pump to facilitate the drainage. As you can expect, this proves to be a point of maintenance and failure. He said his company was already fielding many calls from mini split clients, from clients that didn't use them for installation. There's also apparently a shortage of qualified and knowledgeable technicians to handle the installation and maintenance.

Thanks for the explanation and passing along some concerns with minisplits. I definitely don't want something that's going to cause maintenance headaches if that's the case with all of them.

 

[Justfebreezeit]

4 ton unit on 2300 sq ft. Split about 1300 downstairs, 1000 upstairs. I think it'll be well oversized for just cooling 1300 sq ft if I'm adding another unit to cool the upstairs, right?

Maybe a dumb question but for swapping to a smaller unit, will companies be willing to do it for free if they are getting a 2 year old unit that's pretty new in the swap? Should I just sell the 4 ton unit myself if I won't get much credit back from them on it? Be a shame to get no value back for such a new unit.

You can definitely ask around. I know some companies here that would buy it from you. Here in soflo the craigslist market is alive and well as landlords try to gobble up units like this for good prices. I'm not sure you'll get what you want for it but its worth a shot.

Yeah 4 tons would be to much for what would end up being 1500 sqft. To bad it would have made it easy!

Your best bet is to call companies and have them come give you a quote for their solution and weigh your options.

Good luck!

 

[FarmerTy]

You can definitely ask around. I know some companies here that would buy it from you. Here in soflo the craigslist market is alive and well as landlords try to gobble up units like this for good prices. I'm not sure you'll get what you want for it but its worth a shot.

Yeah 4 tons would be to much for what would end up being 1500 sqft. To bad it would have made it easy!

Your best bet is to call companies and have them come give you a quote for their solution and weigh your options.

Good luck!

Thanks for all your help and great advice! I wish I could give you a reef2reef "good guy" badge! Time to get some more quotes before the 100 degree weather hits!

 

[vetteguy53081]

Dehumidifier will do wonders.

 

[PhreeByrd]

FarmerTy, in your original post you covered the best available options. I design HVAC systems big and small every day, and I can assure you that you've received as much misinformation here as you have good info... and IMO, you were on the right track from the beginning.
You can NEVER mix air from a garage with habitable spaces. I don't care if you use it as a greenhouse or keep your mother-in-law there. It's still a garage, and as such, it must be kept separated from the rest of the house. With that said, as long as you're not mixing any air from the garage with the rest of the house, the separation can be easily maintained.
From what you've described, a mini-split is the type of system I would recommend. Portable A/C units are temporary solutions (think Band-Aid). A through-wall self-contained system would also be a good choice. The most appropriate/permanent type is commonly known as a PTAC (Portable Terminal Air Conditioner), and if you've ever stayed in a hotel or motel, you probably have seen and used one. They require a rather large hole through the wall which, in an existing structure, requires some framing modifications along with all of the associated finish demolition and restoration. But they are a standardized size, so once installed, replacing an old PTAC is very simple and easy. Like mini-splits, they can be either cool-only or heat-cool. Unlike mini-splits, they can only serve a single space.
Mini-splits come in many forms. Cool-only, heat-cool, single-space, or multiple space. Every major HVAC equipment manufacturer has mini-split systems available. Not all manufacture their own systems -- many just rebrand equipment made by other manufacturers, or have their products made by another manufacturer. The huge advantages to a mini-splits are very high efficiency and simple installation. You only need a hole through the wall large enough to bring in two small refrigerant lines and (usually) a power feed from the outdoor section to the indoor section. Assuming the indoor section can be installed on an exterior wall, the condensate drainage can go directly through the wall and drain by gravity outside, so you don't need to worry about a condensate pump to fail or maintain. The indoor section can be one of several different forms. I would expect almost any reputable HVAC contractor in your area to have experience installing mini-splits.
Really, to get all of the correct information, find a good HVAC shop and have them come out to look at your situation. They can help you size and configure the system to address all of your concerns.

 

[PhreeByrd]

I meant to mention, but forgot: Many mini-split systems include a dehumidify-only setting, which is excellent for a fish room. It can maintain lower humidity even when room cooling is not needed. I'd look for that feature in whatever systems you consider.

 

[cdklos]

Great point about the de-humidification with the mini-split and the PTAC unit. Both could be great options depending on the way the house is built and such. We install a lot of PTAC units.

 

[FarmerTy]

Great point about the de-humidification with the mini-split and the PTAC unit. Both could be great options depending on the way the house is built and such. We install a lot of PTAC units.

Thanks for chiming in as always! I never knew PTAC was an option... May not be my solution with the larger hole required but I would still like to research it.

FarmerTy, in your original post you covered the best available options. I design HVAC systems big and small every day, and I can assure you that you've received as much misinformation here as you have good info... and IMO, you were on the right track from the beginning.
You can NEVER mix air from a garage with habitable spaces. I don't care if you use it as a greenhouse or keep your mother-in-law there. It's still a garage, and as such, it must be kept separated from the rest of the house. With that said, as long as you're not mixing any air from the garage with the rest of the house, the separation can be easily maintained.
From what you've described, a mini-split is the type of system I would recommend. Portable A/C units are temporary solutions (think Band-Aid). A through-wall self-contained system would also be a good choice. The most appropriate/permanent type is commonly known as a PTAC (Portable Terminal Air Conditioner), and if you've ever stayed in a hotel or motel, you probably have seen and used one. They require a rather large hole through the wall which, in an existing structure, requires some framing modifications along with all of the associated finish demolition and restoration. But they are a standardized size, so once installed, replacing an old PTAC is very simple and easy. Like mini-splits, they can be either cool-only or heat-cool. Unlike mini-splits, they can only serve a single space.
Mini-splits come in many forms. Cool-only, heat-cool, single-space, or multiple space. Every major HVAC equipment manufacturer has mini-split systems available. Not all manufacture their own systems -- many just rebrand equipment made by other manufacturers, or have their products made by another manufacturer. The huge advantages to a mini-splits are very high efficiency and simple installation. You only need a hole through the wall large enough to bring in two small refrigerant lines and (usually) a power feed from the outdoor section to the indoor section. Assuming the indoor section can be installed on an exterior wall, the condensate drainage can go directly through the wall and drain by gravity outside, so you don't need to worry about a condensate pump to fail or maintain. The indoor section can be one of several different forms. I would expect almost any reputable HVAC contractor in your area to have experience installing mini-splits.
Really, to get all of the correct information, find a good HVAC shop and have them come out to look at your situation. They can help you size and configure the system to address all of your concerns.

Wow! Thank you for the detailed and well-guided advice! I'll be reaching out to a local AC company to peruse my options but I'm armed with so much more knowledge now from all of the great responses like yours that I feel capable of reviewing my options with them.

I meant to mention, but forgot: Many mini-split systems include a dehumidify-only setting, which is excellent for a fish room. It can maintain lower humidity even when room cooling is not needed. I'd look for that feature in whatever systems you consider.

That's what initially had me interested in the portable AC units as they had dehumidify options but it looks to be temporary and slightly inefficient solution for the fish room and doesn't help address the whole house issue at all.

 

[GrouperStupor]

I meant to mention, but forgot: Many mini-split systems include a dehumidify-only setting, which is excellent for a fish room. It can maintain lower humidity even when room cooling is not needed. I'd look for that feature in whatever systems you consider.

True. I leave my on the low dehumid setting most of time. Drainage is not a problem for me. Mine show an error on the screen and won't run without drainage. Only one of mine has a pump. It had the option to come with a pump, but instead I used the $40 pump they use on some regular HVACs (that need a pump). Been working 8 years, so far.

All the options mentioned sound good to me though. If you can get something to work with your HVAC or upgrade it, I guess that would the least worrisome.

 

[FarmerTy]

True. I leave my on the low dehumid setting most of time. Drainage is not a problem for me. Mine show an error on the screen and won't run without drainage. Only one of mine has a pump. It had the option to come with a pump, but instead I used the $40 pump they use on some regular HVACs (that need a pump). Been working 8 years, so far.

All the options mentioned sound good to me though. If you can get something to work with your HVAC or upgrade it, I guess that would the least worrisome.

That is good to know about the dehumidify option of mini-splits!

 

[fab]

What about salt corrosion of large systems.

 

[k2-]

I know its almost 15 years , what option did you choose and what was your experience ? I am considering a mini Split in my garage fish room.