RO/DI water input Temperature

[trivan]

Hi, I was researching getting a new RO/DI unit from Air Water and Ice, when I reviewed the specs it specified that the recommended temp is 77 degrees. I currently have my old unit directly to the cold water line.

Anyone do any plumbing to get the hot and cold water mixed prior to going to the RO/DI unit? I was thinking putting in a shower temperature mixer so it can self regulate the temp going in.

 

[Widdy]

I was doing the same thing via faucet adapter. But a few people here mentioned that the hot water line contains higher TDS/metals than the cold water line; I assume because hot water is sitting in a boiler which is much dirtier, but that's just my assumption. Since then, I've been running pure cold water.

My cold water TDS is 160-165ppm, hot water reached up to 210ppm.

 

[batt600]

It depends on your water i use the hot and cold to get it to 75deg and my tds jumps from 27 to 31 not that big so its good for me

 

[trivan]

I guess I'll have to test my hot, but I'm thinking a cheap water temp regulator would do the trick. Off to home depot to check things out.

 

[Widdy]

What is your goal? Increase productivity? Few weeks ago, I wanted to get the most of out of water production. I ended up adding a 2nd 75gpd membrane which doubled my production, but due to lower than required PSI, I had to add a Aquatec booster. Now I'm getting 5g/40minutes; I was averaging 5g/1hr 45min before and a lot less waste water.

 

[batt600]

What is your goal? Increase productivity? Few weeks ago, I wanted to get the most of out of water production. I ended up adding a 2nd 75gpd membrane which doubled my production, but due to lower than required PSI, I had to add a Aquatec booster. Now I'm getting 5g/40minutes; I was averaging 5g/1hr 45min before and a lot less waste water.

Dame i have 5 stage RO/DI 1 75gpd membrain and a booster pump as well with just cold water it takes me 45m for a 5 gallon bucket with the hot and cold water temp at 70deg it takes 20m to fill a 5g bucket

 

[saltwaterinbrooklyn]

I have the airwaterandice typhoon compact unit and I have it hooked up with the faucet adapter and it threads right on it's easy to use but as far as the water is concerned the temp makes a difference I also mix temp of hot and cold at the faucet but it is true that hot water is higher in mineral deposit and rust particles so the filters will clog a lot faster and as a matter of fact my filters are pretty dirty and I only have been runing it since October and I have a very slow drip and I think it's cause of the filters and the cold water it takes longer in the colder months this is a fact.

 

[Widdy]

Dame i have 5 stage RO/DI 1 75gpd membrain and a booster pump as well with just cold water it takes me 45m for a 5 gallon bucket with the hot and cold water temp at 70deg it takes 20m to fill a 5g bucket

Wow that's pretty impressive.

 

[batt600]

Wow that's pretty impressive.

I think it depend on your membrain ratio of waste water and no waste water dont remember what it should be bought my membrain a year ago.

Just remembered ist 1:2 ratio 2 gallons of pure water and 1 gallon of waste water.

 

[trivan]

I'm really just going by what is from the web site, not having to waste a lot of water is a plus. I don't mind changing filter more in order to save water.

 

[Widdy]

If you don't mind your current speed of production, then let's not apply a fix to something that's not broken. I was doing fairly large WC for my 75g system, and was tired of waiting almost 6 hours for 30g to be filtered; hence my crusade for faster production. I indeed found it, but it cost me about $200. $75 for membrane kit/membrane and about $125 for Aquatec Booster pump.

 

[trivan]

Thanks for all the input. I will be ordering a new unit some time very soon so nothing is really broken. I'm just trying to get it running at the most optimal and efficient way. I might go low tech and just add 2 ball valves mixing both hot and cold to a single line to the RO.

My sink is leaking near the RO unit so I'm doing some plumbing work tomorrow anyways.

 

[rkaragozler]

trivan, what you are looking for is a single lever shower body kit,

 

[masterswimmer]

The need to replace your filters more frequently will certainly occur due to the use of hot water. A great alternative method to get your source water temperature closer to the 77 degrees that is recommended is this:

Take an empty 5g salt bucket and add a long coil (about 50') of RO Tubing connected from your cold water pipe to the first stage input of your RO/DI filter. RO Tubing is very cheap. It'll only cost you about $7.50 for a 50' length of tubing.

Add hot water to the 5g bucket.

Put a small aquarium heater (maybe 75w-100w) and set it to about 85 degrees.

As the cold water runs through the tubing in the hot water 'reservoir', it will heat up the water in the tubing enough to get it to approx. the optimal temperature you need, without the concern of adding additional unnecessary TDS to your source water.

I would also cut small holes in the lid of the 5g bucket to permit a tight fit of the RO Tubing and heater cord to pass through into/out of the bucket to conserve some heat.

Hope this helps.
Russ

 

[trivan]

The need to replace your filters more frequently will certainly occur due to the use of hot water. A great alternative method to get your source water temperature closer to the 77 degrees that is recommended is this:

Take an empty 5g salt bucket and add a long coil (about 50') of RO Tubing connected from your cold water pipe to the first stage input of your RO/DI filter. RO Tubing is very cheap. It'll only cost you about $7.50 for a 50' length of tubing.

Add hot water to the 5g bucket.

Put a small aquarium heater (maybe 75w-100w) and set it to about 85 degrees.

As the cold water runs through the tubing in the hot water 'reservoir', it will heat up the water in the tubing enough to get it to approx. the optimal temperature you need, without the concern of adding additional unnecessary TDS to your source water.

I would also cut small holes in the lid of the 5g bucket to permit a tight fit of the RO Tubing and heater cord to pass through into/out of the bucket to conserve some heat.

Hope this helps.
Russ

Thanks, that is a great idea, I seem to remember doing something like this when I was making beer to chill down the brew fast for bottling.

I was just thinking, if I'm keeping salt water around for WC it's going to be at 78ish degrees, I can just use that as the heater. I'll be testing the TDS out of my water heater tonight. I'll also be switching to a tankless in a few months so the TDS should be lower from that.

 

[kaOzGrUnT]

I use a small container with a 10gal heater, I run about 10 feet of water line into the small container and that brings the temp of water going into my 7 stage.