Author Topic: DIY heat exchanger (Read 4394 times)

DarinSchmidt · « **on:** May 22, 2011, 14:24:24 »

Over the past winter, i noticed a breeze through my house. It was coming from the windows. Who knows how long they have been there though they look relatively new. So i decided to help with my heating bill by sealing them with some plastic and tape. IT worked really well, reduced my fuel bill almost in half. BUT i started to get condensation really bad in the house because of the large tank. So i been looking for something to solve this problem. I had been looking at dehumidifiers for the past couple months and read some reviews only to notice that many reported an increase of at least $50/mo on their electric bill. Well thats not acceptable to me. So i saught out another solution and came across a heat exchanger. Typical commercial models cost close to a grand, some as low as 500. Thats not acceptable to me either, so iI'll be attempting to make my own for hopefully around 200.

So far, this is the parts list that i think I'll need:

HIH-4000-001 Humidity sensor with a variable voltage output.

Trim POT 1w 100ohm (not sure yet as i havent calculated it but I'm thinking that should be enough as I'll only need to adjust 1-2volts)

Copper tubing
Housing box
couple fans
12v PC power supply
Air Filter
Louvers for exterior wall
Relay (something that will kick on at 1-2vdc and supply 12v to the fans)

For those who arent familure with a heat exchanger, all it does is brings in outside air through the unit (either by passing through the copper tubing our around the copper tubing, warms it up, then enters the house, expelling inside air that has been cooled. Helps reduce Humidity and is verry energy efficient as there are minimal parts to power.

This might need a drip pan as the humidity inside the warm air would condense around the copper tubing. Or a drip tube could be led outside.

Not sure where i will install this yet as it needs to be easily accessible to change filters and for repairs if need be.

The Sensor puts out a voltage based on the relative humidity, accurate +-3%. Once it reaches a certain output voltage, ex 70%RH (relative humidity) puts out 2.5vdc, the relay will engage and turn on the two fans. One sucking air in, another sucking air out.
This device, shouldnt be any bigger than an electrical Panel if done correctly. The fans will be a low CFM to allow max heat transfer via the copper tubing.

If anyone has an input, please share. Still doing research on parts, etc.

slandis3 · « **Reply #1 on:** May 22, 2011, 16:37:05 »

This is what I am going to build. I am going to use coroplast for ans exchanger. Much cheaper than a copper one and a lot of the diy forums are using these. Menard's carry's 4'x8' sheets of it for $20-$30. I am going to use 250cfm 110v fans to push the air in/out. I am going to use l channel for a frame work and shin it in either aluminum sheet stock or maybe some hard plastic sheet stock my shop throws away.

Wall_Tank · « **Reply #2 on:** May 22, 2011, 17:24:54 »

Well let me know how it works. I've been thinking about putting one in. Although I was doing it just for fresh air......I'm not sure it's going to do much in the way of humidity control.

slandis3 · « **Reply #3 on:** May 22, 2011, 17:28:04 »

In the summer time it won't do much but the winter time it should work great. If you pushing out air from around the tank and bringing in dry air from outside it will drop the moisture level in the house. Scott Wilson installed one in his house when he had his system running in the basment and he said he could see a difference with in a week.

DarinSchmidt · « **Reply #4 on:** May 22, 2011, 17:56:41 »

How much is the defference in price between coriplast and copper also what is the efficiency rating of coriplast at being a heat exchanger? I had seen that design online earlier today. I wasn't sure yet how it was made. But I didn't think it would take much copper.

slandis3 · « **Reply #5 on:** May 22, 2011, 18:05:31 »

The only place I found copper that was a good size to make the exchanger was mcmaster care. I think it wad around 200+ shipping for copper. I think the coroolast will be about $60

Boonjob · « **Reply #6 on:** May 22, 2011, 19:09:35 »

Not sure if your set on the exchange or if it would work for your specific application, but almost all phosphate material wiether new or used can be used to suck up excess moisture in the air and it works rather well, comparable to prducts such as damp raid... and it is all rechargeable for the most part. you put the media in an open strainer over hanging a collection cup( you can do several cups around the house) I do one a room as the emdia sucks up water it can only hold soo much and the excess runs down into the collection cup where you simply pour it down the drain... if your media is saturated simply spread it over top of a cookie sheet and bake at roughly 450 for one hour, just rinse and repeeat this process as needed... your already buying the media and cost little to no electric to run..

I'll show you a pic of one of my cups and how much water it pulls from my air in a week. I run 4 in my basement and one in every room from there up... I have zero humidity problems

DarinSchmidt · « **Reply #7 on:** May 22, 2011, 19:17:57 »

Do you have a humidity sensor? I'd like to know what your humidity is during the winter. And remember, I have a 300g tank that I have to put a little over a gallon a day due to evaporation.

Boonjob · « **Reply #8 on:** May 22, 2011, 19:28:39 »

No I don't have a sensor, however when I moved into this house it had a humidity problem, I used to run a dehumidifier(the footer at the foundation was leaking in heavy rains from run off on the driveway.) I also experienced condensation on my glass and copper water pipes if i turned of the dehumidifier for any duration of time...as you already stated it is a little expensive to run a decent dehumidifier, and so I started to look into other products, I started with damp raid and buying it in bulk buckets and spreading it around the house monthly(it worked great but was still expensive and not rechargeable, and one I started researching the phosphate materials for my tank I noticed almost all of the material can be used for this same purpose so I switched out certain containers in different parts of my house with my spent media and yielded the exact same results as the damp raid but is rechargable...

Like I said my tank is no where near as large as your, I do however have the 55gal(77gal in total water volume), I have an open sump atm in my foundation that my utility room drains into which is pumped up to sewage(it puts off a decent amount as the washing machine runs non stop rofl). And I can't say much about the footer as I fixed all of that and have yet to have any ill effects since.... but I still pull a good amount of water every week per collection cup(partly due to me living so close to the river imo)

You could always try it and see if it works to your likings...your already using the media for your tank? so instead of throwing away the expelled media from your reactor etc just recharge it in the oven and give it a shot... You just may need more cups or larger cups than me to yield the results you want... obviously more media will be able to pull more moisture...

The only diff between the damp raid and the phos media I have noticed is the damp raid lets of a scent when it is working(like clean laundry), the phos media has zero scent, and the phos is rechargeable, the damp raid has to dissolve to work.

Boonjob · « **Reply #9 on:** May 22, 2011, 19:31:01 »

Quote from: DarinSchmidt on May 22, 2011, 19:17:57

I have a 300g tank that I have to put a little over a gallon a day due to evaporation.

I honestly no joke am finding myself doing almost this same amount on my tank...I have to top off twice a day(due to my sump design) and it fill almost a half gall every time. But the cups weekly easily pull 8oz per cup back out of the air.

DarinSchmidt · « **Reply #10 on:** May 22, 2011, 19:47:39 »

how often do you have to cook (recharge) them?

slandis3 · « **Reply #11 on:** May 22, 2011, 19:51:55 »

I am looking to building and exchanger for 2 reasons, get rid of the moist air and bring in fresh. The room my tank is in is about 240sq' so its a small room with a large amount of water and fish. My skimmer filled the room with nasty skimate smell so bad within a day I had to vent it out side.

DarinSchmidt · « **Reply #12 on:** May 22, 2011, 19:53:48 »

thats interesting, doesnt seem to be a way to make it maintenance free though, unless you were to have a fan cycle your air through it and drain it outside somehow. My water heater has a drain pipe that leads outside and thats where i planned on hooking up the heat exchanger. I havent found any official prices on how much extra it costs anyone, but using the p04 granules wouldnt be a bad idea as you wouldnt have any wasted heat going outside.

Boonjob · « **Reply #13 on:** May 22, 2011, 19:56:41 »

It honestly depends, usually around 1-2 times a month, I try to do them all together even is certain ones don't need it. However over the last month and a half I have done it almost weekly I am at 4 times(but that is because of the excess water in the air to begin with.) Though in the winter the water production slow significantly to right around 1-2 times a month...

I should also notate that I only put the aquarium in the home since end of January (though I have been running either damp raid or a dehumidifier since the day I moved in. So I can't say for sure what the exact results are over the course of several winter months... and I also use my fireplace quite frequently in the winter to save on gas and it can and almost always does cause my air to become to dry so I either have to stop the dehumidifying agent I have going at the time to allow it to balance out, or I add a wick humidifier to compensate in drastic situations where I can't bring the humidity back up fast enough.

slandis3 · « **Reply #14 on:** May 22, 2011, 19:58:01 »

I have a drain line going out for water changes so thats not a problem for me. I don't run any phos removal media so I would have to buy some or get it from people that would normally throw it away.

DarinSchmidt · « **Reply #15 on:** May 22, 2011, 20:00:36 »

idont typically use phos remover media either... hmmm, We shall have to see a test over the next winter then. We can all use our methods and see (of course compensate for tank size) and see which works best maybe???

Running the oven for an hour every week or two isnt bad at all, def not much energy needs, but i'm worried that the maintenance would just become neglected eventually.

Boonjob · « **Reply #16 on:** May 22, 2011, 20:01:17 »

Quote from: slandis3 on May 22, 2011, 19:51:55

I am looking to building and exchanger for 2 reasons, get rid of the moist air and bring in fresh. The room my tank is in is about 240sq' so its a small room with a large amount of water and fish. My skimmer filled the room with nasty skimate smell so bad within a day I had to vent it out side.

Yes, I completely agree with this, I believe if the tank is as large as it is in this case with the room being as small and enclosed at it is, it would be much more efficient to use the exchanger.. I don't believe a reasonable amount of media would be able to pull enough moisture quick enough to make a difference... Also it would not rid any scents produced by the tank..

However for people with an open floor plan and a smaller tank and on a budget I see no reason why the phos media would not perform as expected in the correct amounts.

Boonjob · « **Reply #17 on:** May 22, 2011, 20:11:51 »

another idea that I read about using the phos media for in this manner; is to use it in unison with ozone.... I plan on testing this aswell

DarinSchmidt · « **Reply #18 on:** May 22, 2011, 20:22:22 »

i thought about using an ozone as well, i just dont know much about it yet to discuss that.

DarinSchmidt · « **Reply #19 on:** May 23, 2011, 11:47:23 »

For the heat exchanging core, i was thinking, instead of using copper tubing like i planned, what if you used tin foil. Just layers of it seperated by some thin acrylic or something? Tinfoil transfers heat well because its so thin. Just glue the layers together and set the system up just like in the diagram on the first page??

Boonjob · « **Reply #20 on:** May 23, 2011, 11:54:37 »

Not sure if you want to use it or incoporate it into your design but I have a brand new range hood at my house for a stove(white), never been used(think it is a broan) if you enclosed it right it should provide suffiecent flow or at worst you could disasemble it for the fan, it has a filter and everything unless I'm mistaken, I'd let it go for 30 if you were interested.

DarinSchmidt · « **Reply #21 on:** May 23, 2011, 12:04:01 »

can you post a pic and the dimensions?

Boonjob · « **Reply #22 on:** May 23, 2011, 12:29:52 »

it is a 30" broan model#f403011 has two settings low(120cfm) and high(190cfm)... It has a light(not that you'd need it) Its brand new never even taken out of the box... here is the pic and stats below...

http://www.amazon.com/Broan-F403011-30-Inch-2-Speed-Convertible/dp/B000AMGV92

DarinSchmidt · « **Reply #23 on:** May 23, 2011, 12:41:20 »

Not sure if that will work or not, but i'll keep it in mind. Thanks

Boonjob · « **Reply #24 on:** May 23, 2011, 13:48:11 »

Quote from: DarinSchmidt on May 23, 2011, 12:41:20

Not sure if that will work or not, but i'll keep it in mind. Thanks

All good I personally thought it was more cfm than that.

2024 Ohio Reef Frag Swap

Author Topic: DIY heat exchanger (Read 4394 times)