Water Softeners and Air Filtration Systems - softener plus RO?

We have a whole house water softener system (can't remember what kind it is and I'm not at home). I'm thinking about adding an undersink RO system to the kitchen faucet. We have a Pur filter on it now but they keep breaking because they're always in the way when washing dishes etc. Nobody in the house likes drinking the softened water, so I figure this will help us stop buying so much bottles water. Plus I can hook up a liine to our refrigerator and finally get the ice maker working.

I have a system in mind, but I can't remember what it is (sorry). I have the link saved at home from when I was looking into this a couple of years ago at our other house. I got it from a thread at this site, so it must be a good one. : )

So my question is can I do this? Will an RO system work right on already softened water?

Yes. In fact softened water is the ideal pre-treatment for ROs. It will significantly remove sodium and other minerals, metals (and a large number of other elements) and salts from the water.

Be careful with fridge hook-ups. Newer fridges have shut-off solenoids that open for maybe 7 seconds. If your RO doesn't produce enough pressure to fill the trays by then, they will not work as you hoped.

Not all ROs are built the same, last as long or produce as good water.

Andy Christensen, CWS-II

Thanks for the reply Andy. I found the link to the unit. It's a Flowmatic 5-stage RO unit, #FMRO5G. It has a 50 gallon capacity per day. It has John Guest fittings that supposedly make it easy to install. Price with frig unit will be around $300.

Our frig is about 4 years old. How can I tell how it operates so I'll have an idea of whether it will work correctly when hooked up? It's a Hotpoint with the freezer on top.

When you read a rating like "50 gpd" be aware your RO will not produce that in normal situations. It is a rating made in laboratory conditions which includes water temps at 77F and 60psi among other parameters. Typically, it wil produce between 9 and 15 gallons per day.

As for the fridge. check the owner's manual or the manufacturer's website. Yours will have an air-bladder style tank, so it will lose pressure as the tank empties. A '3-gallon' tank usually only hold about 1.2 gallons depending on air pressure.

So your fridge doesn't have a water tap, just an ice maker, right? If you can't find the info, just hook it up and see. A booster pump can be added later. You could also upgrade to a ten-gallon tank (holding about 3.5 gallons.

Andy

Wow that's a big difference. But I think that would be plenty for our realistic uses anyway.

The frig doesn't have anything in the door, just an icemaker in the freezer. When you talk about upgrading to a 10 gallon tank I'm assuming you mean the holding tank for the RO unit. I think that's what it comes with anyway, but I'd have to check on that. At that size I think I'd have to mount it under the floor in the crawlspace. That sounds kind of big for undercabinet.

At that size I think I'd have to mount it under the floor in the crawlspace. That sounds kind of big for undercabinet.

As long as it doesn't freeze (and animals don't gnaw on it), that will be OK.

My crawlspace has a concrete floor and doesn't get cold so I won't have any problems there. I was checking the info on the unit mentioned above and they don't say what size the tank is, but if the picture is correct it is most likely 3.5 gallons or so. I didn't see an upgrade to a bigger tank, but then again I didn't look real well yet.

Thanks for the info Andy. I see you're in NW Ohio. I grew up in Toledo. Are you anywhere near there?

A bigger tank is something you can add later and get on your own, easy to connect.

Grew up in Fremont, live in Port Clinton.

Andy

Ok, so I have this thing all installed now. I went to open up the valve to start filling up the system and the hose is leaking at the valve. This system has the 'quick-connect' fittings where you just push the hose into the fitting and an o-ring makes the seal while some kind of barbs or something hold the hose in. I thought this was going to be problem free, but I'm imagining this is just the first of numerous leaks.

I know that the hose ends need to be free of nicks or burrs. This particular hose end was never cut by me before it was installed, so I'm pretty confused as to why it is leaking. These fittings are supposed to allow you to remove the hose by pushing in on a collet where the hose goes into the fitting, but I can't seem to get it out. I was going to cut the end off the hose and try again. What's the trick to getting them out?

there is no real trick, just push the release and pull the tubing out. I'm guessin the tubing was probably slightly curved and I have had that cause leaks for my installations in the past. Also it may make the release mechanism a little tougher to engage. If some extra ummphh isn't enough to get it out then I suggest using a pair of pliers to pull on the tubing as you push against the release flange. That method has always worked for me even if I had to cut the tubing a few inches from the fitting and get real rough with it.

The John Guest fittings are very reliable and if you have a leak I'm guessin you either didn't insert the tubing in far enough or that the natural curve of the tubing is preventing a seal. When you get the tubing out of the fitting, cut the new tubing square and try to make sure it is as straight as possible before inserting it into the fitting. Usually you will feel the tubing kinda of "pop" or "snap" into the fitting as it slides by the o-ring.

As for the "50 GPD only yielding 9 - 15 gallons", I have installed many RO units and never had any issue like that unless the drain restrictor -if required- was not properly installed. If you want to store more water it is probably cheaper and easier for you to just get another tank similar in size to what you have and add it to the system rather than replacing it with a larger tank. Just make sure to add a shut-off for that tank and be sure to use a tank specifically designed for RO units or a fiberglass tank.

Thanks for the reply shane. I'm sure they're seated all the way. I heard them 'snap' as I pushed them in. Curvature of the tubing makes sense; it was all coiled up when it came in the mail. I got some kind of reinforcement with the ice maker kit that used some little brass insert that goes in the end of the tube before it's inserted in the fitting. It looks liike it would stiffen up the end of the tube pretty well. I wonder if I can find more of those at a store? That would go a long way towards controlling the leaks I think. I'll have to work on that this weekend.

Actually John Guest fittings are not made to be used with tubing inserts. Technically I think they tell you specifically NOT to use them with those types of fittings. I know I tried to use one once and when I had to pull the tubing back out the insert got stuck in the fitting and I ruined the "teeth" trying to get it out as the flange got trapped past the "teeth". Every supplier I have ever purchased them from always says not to use the insert as well so take that for what it's worth.

Is the connection still leaking or did you get it fixed?

I didn't have any time to mess with it again this weekend. Weekends are always just too short. It's not actively leaking because I shut the supply off to the filter system, but I'm sure it would be.

That makes sense about the inserts. Now that I think about it I think they were included to be used with compression fittings that I might have had to use depending on which faucet I have. The faucet I have doesn't have a return drain on it. I'll probably have to use a compression fitting when I hook up to the icemaker though.

Hopefully I'll get to look at it soon and report back with the results.

So I got the tubing out of the fitting. Cut it off straight and reinserted it. Leaks just as bad. It's a steady drip. At this point I'm thinking the fitting is bad. It's actually one of those taps that punctures the plastic supply hose and then has a fitting on the side that the tubing connects to. I don't have any leaks where the water supply tubing is punctured, only where the tubing that goes to the RO system goes into the fitting.

I could get another puncture tap and try again, but I think I'm going to get a tee or something that goes right on top of my cold water shutoff under the sink, and then replace my supply line to the sink. I suppose I could leave the tap on the current supply as it doesn't leak at all when the tap is shut off, but it's probably blocking some of the flow to my sink faucet.

Sigh, it never fails. Even projects that seem like they should be simple never go right for me. : )

US DIY's must all be into sadomasochism because nothing ever goes the way we want it to or how we think it should. I guess that is the trade off for the $ saved and the satisfaction of doing it ourselves :)

If the fitting that is leaking is one of the saddle taps then I will have to say I'm not sure where to go from here as I NEVER use those things. I have had to remove too many of them after the "point" broke off in the plumbing and stopped the water completely. I always install a a tee and quarter turn shut off valve to start an installation.

I guess the only thing I can think of is are you sure the packing nut around the handle of the current valve isn't the culprit? I recently worked on an RO for a customer and during the changing of the filters I had to shut off the supply which was a saddle valve. After finishing, the supply line was leaking at the saddle valve and it was indeed the packing around the handle that was the cause. A quick snug of the packing nut and the leak was fixed. Just making sure you didn't miss something easy before you go through the hassle of replacing the valve completely.

Pretty sure, yes. I can see the water seeping from around the tubing as it comes out of the connection fitting. I was going to take the saddle off and try to make sure everything was tight, but I was afraid it wouldn't seal right again when I put it back on so I left it alone. I think I'm going to do like you said you do. That's the way I should have done it to begin with. I thought the saddle would be easier. Turns out it's not. ; )

Pretty sure, yes. I can see the water seeping from around the tubing as it comes out of the connection fitting. I was going to take the saddle off and try to make sure everything was tight, but I was afraid it wouldn't seal right again when I put it back on so I left it alone. I think I'm going to do like you said you do. That's the way I should have done it to begin with. I thought the saddle would be easier. Turns out it's not. ; )

We never use saddle valves. They are cheap and have a more chance for leaking and corrosion. We cut the pipe and insert an in-line tee with ball valve. These are more expensive but provide way better flow and have an convenient shut off at the source. They seal very well.
http://i165.photobucket.com/albums/u44/nalampng/ballvalvetee.jpg


You can cut yours out and add this yourself.

Andy Christensen

I finally got it going this weekend. After numerous trips to the big box stores for fittings (plastic threads strip really easy - don't ask me how I know) I got the leaks taken care of and turned the water on. The start-up instructions said to fill and drain the tank three times before drinking the water. Right now it's on the third regeneration.

The only other problem I might have now is I'm not sure if the tank is filling all the way. When I open the faucet to drain it I only get what looks to be about a gallon of water before the flow stops. It's a 4-1/2 gallon tank, and I know I should only get about maybe half of that, but it just doesn't seem like I'm getting enough out of it. Is there something that would cause the system to not fill completely? Or do I just need to get a bigger tank right away?

Are you sure you are giving it enough time to fill the tank? I know Andy said something earlier this thread about seeing some units claim 50 GPD but they only produce maybe 15 GPD. If that were the case it might take 3 hours to fill your tank, are you giving it that long before draining it?

You can play with the air charge in the tank to get more water if you need it. The lower the air pressure in the tank - have to check it when the tank is empty of all water - the more water it will store. The trade off is of course the as you lower the air to store more water, the extra water will be supplied at a reduced pressure.

You are experiencing the biggest issue with RO systems and seeing why so many people choose to have something done to boost the production or pressure rates. The cheapest option is adding a second tank but a booster pump and a much larger tank to replace the current one are options also.

I've been waiting 12 hours each time so far. The instructions said 6-10 hours, depending on incoming pressure, etc, so I gave it the benefit of the doubt. I should have drained it this morning before I left for work but forgot, so it will be 24 hours when I get home and do it again. It will be interesting to see if there's a difference.

I was checking for leaks this morning and thought I heard water running in the system so maybe it's just taking a really really long time to fill. I don't know what our incoming water pressure is, but I'm going to say it's more than adequate as we have plenty of pressure from showers and sinks.

Is it possible that I have the membrane cartridge in backwards? There was no diagram on inserting it so I just took a stab at it. I think if I would have put it in the opposite of the way I did I wouldn't have been able to get the cap back on the housing.

The RO unit should shut off when it's full and up to designed pressure. If you are uncertain just check the drain line. If it has water running out of it then it's still making water, if no water then the system is "full"

As for the membrane being upside down I don't think I have ever seen one installed incorrectly but that doesn't mean you can't be the first :) If in doubt call the manufacturer and verify membrane position is correct. I can't imagine they would package it w/o any installation instructions if it was possible to install it upside down and impossible to tell the difference.

Well, it all seems to be working alright. I've cycled it a number of times and now we're using the water. I only get one gallon of water out of it before the tank runs out and it has to fill again. I've confirmed that it is not leaking into the basement. That doesn't sound right to me from a 4-1/2 gallon tank, but then I've never had this type of system before. I'll keep investigating and then decide if I want to upgrade to a bigger tank or not.

Thanks all for the responses.

Croc, how much air is in the diaphragm/bladder of the tank? Give me that number and I will tell you if it's yielding the correct amount of water. I can also let you know how much to let out or add if you want to increase/decrease the storage capacity of the tank.

According to the documentation it's supposed to be preset at 7 psi. I'd have to find a more accurate gage than I currently have to verify my actual charge. From my investigation it seems that the incoming water pressure has a lot to do with how much filtered water the system will make and how quickly it will make it.

I said in an earlier post that I think the pressure is adequate, but since I've never measured it I don't really know what that is. Our water supply is 'city water'. It doesn't come from a well in our yard or from a neighborhood well. I could probably find out what the city measures it at after the pumps, but I'm sure it decreases as it gets out in the lines. How does a booster pump work? Does it only increase the pressure into the filter system?

Booster pumps can work on either side of the RO unit. I prefer to put them AFTER the unit so I don't "force" water through the unit faster keeping it from doing it's optimal job. A booster pump won't help a whole lot though if your tank is only holding a gallon of water. I would think a 4.5 gallon tank with 7 PSI air should hold somewhere in the neighborhood of 3 gallons or so. Maybe after you run the 1.5 gallons your talking about the pressure is just so low it trickles out of the RO faucet?

Putting a booster pump on the line after the tank is what I prefer but I always try to make sure it won't pull negative pressure on the tank (unless left open for 5 minutes straight). A pressure gauge on the line feeding the RO and a pressure gauge on the line after the tank might help you determine what the actual problem is.

After I get a gallon out of the faucet it does reduce to just a trickle. I've never left it on for very long after that to see what happens. I've just assumed it was almost empty. I suppose I could go down and slosh it around some and see if it feels like there is an appreciable amount of water left inside. I'll try to get some pressure readings before the filter and after the tank and report back with what I find. It'll probably be at least a few days. Thanks for your patience. : )

Ok, so where do I find a decent gage to use to check this? The big box stores don't carry anything I could use. I haven't checked anywhere like an Ace Hardware yet, but I'm guessing they won't either. I'm thinking I'm going to have to find a plumbing supply store of some kind. Sounds expensive.

Most big box stores should carry a pressure switch with 1/4" pipe thread in the water well section. If not you should be able to find one pretty cheap somewhere. I know we sell them for $4.65. I would not recommend leaving the gauge on the line because RO treated water is pretty aggressive and will attack that brass gauge. Leaving the gauge on the input line will be fine though if you want to.