Removing Mixing Valve on Water Heater


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Old 01-07-09, 05:12 PM
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Removing Mixing Valve on Water Heater

I just had a guy from Enbridge in here because the water coming out of the hot water taps is not hot. It never has been. He is the 3rd guy to come out for the same problem. I'm glad I got this guy, because he actually explained to me what the problem is. It's this thing called a 'Mixing Valve' which is a burgundy knob with temperature markings connected to the pipes above the water heater. Apparently, these things are being put into homes everywhere without the owners requesting them or even knowing what they are. A mixing valve prevents the temperature reaching your taps from exceeding 120 F, which is somewhere around 40-50 C - warm, not hot. My back is completely shot from working on this house and I need hot water, but it took until just a few minutes ago to discover why I could never get any. I insulated the pipes, I turned the temperature up all the way inside the water heater, nothing made any difference.

So my question is, if I remove the mixing valve, do I require any special skills to cap something, or solder something in place, or add a section of pipe or anything? Or can I just remove it? I have very basic plumbing skills. I can solder pipe under ideal conditions. There is one screw holding the valve in place. If I unscrew it, what would happen? I am assuming that removing it would then create a new problem which I would have to solve.


100_2033 by noahbody on Zooomr
 
  #2  
Old 01-08-09, 09:22 PM
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I know it is dumb to ask, but have you turned the valve to a hotter position? Are all your shower/tub control valves temperature compensated or scald proof?
 
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Old 01-09-09, 06:24 AM
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You can't turn the valve without unscrewing it. There are 2 temperature markings on it: 49C and 32C. I don't see how you can tell which temperature it is currently set to. It might already be at 49C.

To the best of my knowledge, there are no anti-scald or child-proof temperature dials or locks anywhere else in the house. I have even torn down some walls and have not found anything like this behind any bathroom or kitchen walls which I have torn down, at least not yet.
 
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Old 01-10-09, 06:39 PM
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Get this: 4 plumbers have been in here, if you include the guy from Enbridge. The first one replaced an element, which had no impact on the water temperature. The 2nd one didn't have any suggestions regarding the water temperature. The 3rd one suggested that I buy a new water heater, so he didn't really understand the problem. I thank the Enbridge guy for finally explaining why I can't get hot water, but he refused to touch the mixing valve and he refused to consider removing it. He said it's not his problem because it's not part of the rental. I'm pretty sure they were both installed at the same time by the same person, but whatever.

So with that kind of help, I really may have to do it myself. Good thing this website is here...

I unscrewed the knob to see why it wouldn't turn when I tried to adjust the temperature. I still can't twist what's underneath it, but then, I don't have the correct size socket wrench.

Here's some more pictures. Any suggestions on how to adjust the temperature? I just want to see if I can adjust it first before making plans to completely remove the thing.



 
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Old 01-11-09, 07:59 PM
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First, the tempering valve may well be required by code, so you do not want to mess with that. It is a safety item, to prevent scalding. Now, check your temps and your numbers. 120 is too hot to shower in. (see chart below). You would mix a little cold in with that. If you cannot get water at about 105 to 110, then maybe the tempering valve needs to be adjusted.


TIME / TEMPERATURE RELATIONSHIPS IN SCALDS
125 F 1 1/2 to 2 minutes
130 F About 30 seconds
135 F About 10 seconds
140 F Less than 5 seconds
145 F Less than 3 seconds
150 F About 1 1/2 seconds
155 F About 1 second
Table courtesy of Shriners Burn Institute
 
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Old 01-11-09, 08:43 PM
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I appreciate your advice.

The issue here is that the temperature is not even hot. It is lukewarm. I have to go to a public gym to take a hot shower. This is not right. I own this house, and I have the right to take a hot shower in my own home.

I am trying to determine how to adjust this mixing valve. I have brought in 4 plumbers and none of them could/would help. If I cannot find somebody to help me, I will have to try to remove it myself.

I'm not that old, but I was around before they started installing these mixing valves in peoples' homes. You could take a hot shower and wash dishes in hot water back in those days. Now, there is a law being passed to prevent people from ever taking any kind of risk at all.

I don't require this mixing valve if it is going to only give me lukewarm water. The water is just as warm as in the swimming pool at the gym.

If you can scald yourself at 120F, as it says in your advice, then I'm obviously not getting 120F.

I tried turning it with all my strength, but it didn't move. So I removed the screw holding it in place. What was underneath is in the most recent photo, below. I don't know what to do to the part which is underneath - it doesn't want to turn either.

So if somebody can tell me how to adjust the temperature.
 
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Old 01-13-09, 01:02 AM
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I don't know if this will help but here is a link to the manufacturers website.

Powers: LM490/LM490-10 Series | HydroGuard Series LM490 Thermostatic Tempering Valves for Hot Water Heater & Multiple Lavatory Installations

Over the course of time all tempering valves or anti scald valves seem to go bad and If you have well water, the guts inside the valve can get plugged up with crud and mineral deposits. That unit has unions on it so try shutting off the water, open up the hot and cold handles on a faucet to remove the pressure from the system, loosen the unions and remove the unit to inspect it. If the inside of the unit if filled with crud or mineral deposits. If it does, let it soak for a day in a container of white vinegar and see if that disolves any of the crap inside it. If it looks too bad you might think about swapping it out for a new one. I have well water and have had the pleasure of changing several tempering valves (Watts brand) in my house. I finally gave up and removed the valve and cut in a copper tee on the cold and hot water pipes and used a gate valve installed between the 2 tees to manually temper the water.
 
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Old 01-13-09, 08:51 PM
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Originally Posted by lightsout06810 View Post

Over the course of time all tempering valves or anti scald valves seem to go bad and If you have well water, the guts inside the valve can get plugged up with crud and mineral deposits...
Thanks for this reminder of why if something is working as designed, don't try to fix it. Thanks to the 'code' and these mixing valves, there are probably tens of thousands of people wondering why their hot water never gets hot anymore. Some of them are probably going crazy because even when they call a repairman or plumber, he doesn't diagnose the problem correctly and nothing gets solved. Or he refuses to work on the mixing valve or remove it and put things back the way they were originally.

I get water from the city. I assume it comes from the lake. No matter, your explanation of what might be happening is very helpful and I have decided to remove the valve and reconnect the pipes the way they would go if there was no mixing valve. Even if I have to pay double to get it done.
 
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Old 01-13-09, 09:42 PM
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One of the most common complaints about water heater is "not enough hot water." You see that all the time on this forum.

Unfortunately, people get all kinds of advice on this, most of it bad in my opinion. "Not enough hot water" can have quite a number of causes, and really requires careful service by an experienced repairman to diagnose the actual cause.

Of course, it's a lot easier to diagnose the wrong cause of this problem, which is what people very often get.


Local repairmen ought to know about a code requirement that requires this kind of tempering valve and be on the lookout for it. They may not be able to remove it, but they should at least tell the home moaner about it.

Unfortunately, this sounds like just another layer of nannystateism by elected officials that have too much time on their hands. If people want that in their homes, that's fine with me. But I certainly wouldn't want the oily hands of politicians requiring that to be installed in my home.



Seattle Pioneer
 
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Old 01-13-09, 10:16 PM
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Originally Posted by SeattlePioneer View Post

Unfortunately, people get all kinds of advice on this, most of it bad in my opinion. "Not enough hot water" can have quite a number of causes, and really requires careful service by an experienced repairman to diagnose the actual cause.
...
Local repairmen ought to know about a code requirement that requires this kind of tempering valve and be on the lookout for it. They may not be able to remove it, but they should at least tell the home moaner about it.

Seattle Pioneer
I've had 4 plumbers/repairmen in here and only one of them bothered to indicate the mixing valve might be causing the problem. The other ones were all over the map - buy a brand new water heater, replace the elements...
I know next to nothing about plumbing and I have no idea if the mixing valve really is causing the problem. However, since the elements have been replaced and 3 Enbridge repairmen have found nothing else wrong with the water heater, and I have insulated the pipes, and when I touch the hot water pipe at the point where it comes out of the water heater, it is very very hot. When I touch the 'hot' pipe after it comes out of the mixing valve, it is only room temperature. So it appears that the mixing valve might be causing the problem.

Out of the 4 guys who have come to my house so far to look at this problem, I'm not getting a great deal of help. The best advice I've received has been in this forum.

I'm going to remove the mixing valve, clean it like lightsout06810 suggested, and put it back.

If this does not make a difference, I'm going to remove it permanently and reconnect the pipes.

If this does not solve the problem, then I'll buy a brand new water heater and have it installed by a professional.

If that doesn't solve the problem, then I really won't know what to do.

I am very suspicious of this mixing valve. This is a new part of the building code. It's so new that apparently many plumbers have never heard of it and are unfamiliar with them. 3/4 of them, in my experience, wouldn't even think to suggest it as being the cause of the problem.

I agree with your comment on the nanny state. I never asked for this problem. I have enough things to deal with already. The government is not helping by making things more complicated than they have to be.

I understand that there needs to be a building code and 9 times out of 10 the rules are there for good reason.

But when the code forces this product on me, a product which deteriorates to the point of being useless after a short period of time; forcing me to waste days trying to figure out what is wrong and then having my time wasted further by repairmen who I need help from, and they can't or won't help, this is one part of the code I can do without.
 
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Old 01-14-09, 05:34 AM
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It would probably pay to purchase a 3/4" nipple the length of the opening to the back of the nuts and remove the valve and replace it with the nipple for testing purposes. At least you will know if it is the valve or not. I wouldn't clean it. I would replace it with a working model.
 
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Old 01-14-09, 05:58 AM
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Originally Posted by chandler View Post
It would probably pay to purchase a 3/4" nipple the length of the opening to the back of the nuts and remove the valve and replace it with the nipple for testing purposes. At least you will know if it is the valve or not. I wouldn't clean it. I would replace it with a working model.
Thanks for the suggestion.
 
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Old 01-14-09, 11:49 AM
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Thermostatic mixing valves have been around for decades, it might just be this particular model is problematic.

I think I would take it apart while still plumbed in place to see if I could clean it, and then try it. You may have to remove it from the piping in order to take it apart. At least you have unions and don't have to cut and re-solder pipe.

If you get real ambitious and want to try another brand of valve then I would cut the piping back farther than absolutely necessary and install shut off valves on the three pipes if they don't already have valves. I might also install a bypass valve to allow continued hot water service when working on the mixing valve.

If you do eliminate the mixing valve (or use a bypass) remember that you can be seriously burned by the hot water.
 
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Old 01-14-09, 01:10 PM
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Originally Posted by chandler View Post
It would probably pay to purchase a 3/4" nipple the length of the opening to the back of the nuts and remove the valve and replace it with the nipple for testing purposes. At least you will know if it is the valve or not. I wouldn't clean it. I would replace it with a working model.
So would I be using a T shaped 3/4" nipple? You're saying to replace the valve with something shaped just like it to test for temperature. So I should go look for something with the same size threads and everything.

I could replace it permanently - I have some extra 3/4" copper pipe here. I would get the proper joints and I would solder it in place. But if I do this, I'm not going to want to take it apart again to install a new valve.
Is this all you have to do to replace the valve? Reconnect everything the way it was, except now with a T-shaped piece of copper instead of the valve? Or is it more complicated than that?
 
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Old 01-14-09, 01:34 PM
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Reconnect everything the way it was, except now with a T-shaped piece of copper instead of the valve? Or is it more complicated than that?
No, you don't re-connect all THREE pipes, just the one from the water heater outlet and the hot water supply to the house would be connected. The third pipe, which is cold water, would be capped.

Again I warn you that elimination of the mixing valve could set up a very dangerous situation in people being scalded by the hot water. This is especially true if the occupants of the house have gotten used to only getting warm water. I don't have a mixing valve in my home and I do have the water heater thermostat set fairly high. Since I live alone AND I am well aware that very hot water can come from my faucets it isn't a big deal for me. Still, I put up prominent labels above my faucets that read: Caution, water may be very hot.
 
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Old 01-14-09, 01:52 PM
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Originally Posted by furd View Post
No, you don't re-connect all THREE pipes, just the one from the water heater outlet and the hot water supply to the house would be connected. The third pipe, which is cold water, would be capped.

Again I warn you that elimination of the mixing valve could set up a very dangerous situation in people being scalded by the hot water. This is especially true if the occupants of the house have gotten used to only getting warm water. I don't have a mixing valve in my home and I do have the water heater thermostat set fairly high. Since I live alone AND I am well aware that very hot water can come from my faucets it isn't a big deal for me. Still, I put up prominent labels above my faucets that read: Caution, water may be very hot.
There's nobody else here. It's just me. And I grew up in homes without mixing valves. You learn how to manage it when you are a little kid. You test the temperature with your wrist first. If it's too hot, you add some cold or use less hot.
I don't need this valve to keep me safe. I know how to mix hot and cold manually. I've never had a problem with it.

So I will attempt to connect the hot water coming out of the tank to the mixed hot/cold pipe and just cover the cold pipe up with something and not turn it on when testing.

I assume I'm going to have to solder this test hot water pipe anyways, so why don't I just solder everything in place the way it should be without the mixing valve? Otherwise I would be soldering the hot water pipe, testing it, - being unable to use cold water to mix it with - and unsoldering it again. It just seems like it would be less work to connect the cold water pipe AND the hot water pipe to the mixed hot/cold pipe. I mean just connect it all now, one time. Then I would be finished.
 
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Old 01-14-09, 02:20 PM
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Well, you could solder in some unions far enough away from the present mixing valves that would allow you to just do the soldering once on the main lines and then you could experiment with a straight line or a line with a teed in connection for the cold water. This would also give you flexibility to try other mixing valves if you ever wanted.

Myself, I would probably just use a pair of "repair" couplings (sweat couplings without the internal stop) and solder in a straight piece of pipe. I'd solder a cap on the cold water line and that would be the end. If the water was way too hot I would simply lower the thermostats on the water heater. Trying to use a manual valve at the source to blend in some cold for use at the sink or shower is an exercise in futility since the temperature will wander all over the place depending on flow rate and the temperature of the cold water. Keep things simple and just adjust the temperature at the point of use as you have done all your life.

One more thing. If the mixing valve is required by local codes then you would most likely have to have it in place and working if you ever decided to sell your home. Something to keep in mind.
 
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Old 01-14-09, 10:55 PM
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I have replaced the mixing valve with copper pipe. The pipe going out of the hot water tank goes directly to the hot water pipe which is distributed throughout the house, without going through a mixing valve. The cold pipe which used to connect to the mixing valve is now capped. All cold water now goes directly to the cold water line which is distributed throughout the house - no cold water gets mixed with hot except at a faucet now.

I tested it for 5 minutes, and it appears that so far, there are no leaks on the sections of pipe I worked on. Unfortunately, a leak has sprung further along on the hot water pipe - an elbow joint seems to have been twisted while I was working in cramped conditions on the section above the hot water tank, and there are now 4 streams of water shooting out of that joint. I have had to turn the water off and will replace the joint tomorrow. Hopefully that will be the the final chapter for this specific problem.

Now, the water temperature coming out of the hot water faucets is exactly the kind of thing I was looking for. The water is really hot! Not hot enough to burn yourself, but it will probably kill more bacteria, and it will make for more comfortable showers.

I would like to thank those who contributed to this thread. Thanks for all the valuable advice.

The manufacturer of the mixing valve, Powers/Watts, sent me an email this afternoon in response to an email I sent them, asking for technical support. I was wondering why on their website they were showing a completely different model from the one I have, so their instructions weren't making any sense. See below.

<link href="cid:filelist.xml@01C9765E.3CEF7820" rel="File-List"><style>@font-face { font-family: Tahoma; } @page Section1 {size: 8.5in 11.0in; margin: 1.0in 1.25in 1.0in 1.25in; mso-header-margin: .5in; mso-footer-margin: .5in; mso-paper-source: 0; } P.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } LI.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } DIV.MsoNormal { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } A:link { COLOR: blue; TEXT-DECORATION: underline; text-underline: single } SPAN.MsoHyperlink { COLOR: blue; TEXT-DECORATION: underline; text-underline: single } A:visited { COLOR: blue; TEXT-DECORATION: underline; text-underline: single } SPAN.MsoHyperlinkFollowed { COLOR: blue; TEXT-DECORATION: underline; text-underline: single } P.MsoAutoSig { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } LI.MsoAutoSig { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } DIV.MsoAutoSig { FONT-SIZE: 12pt; MARGIN: 0in 0in 0pt; FONT-FAMILY: "Times New Roman"; mso-pagination: widow-orphan; mso-fareast-font-family: "Times New Roman" } SPAN.EmailStyle18 { COLOR: navy; mso-style-type: personal-reply; mso-ansi-font-size: 10.0pt; mso-ascii-font-family: Arial; mso-hansi-font-family: Arial; mso-bidi-font-family: Arial } DIV.Section1 { page: Section1 } </style>The e490 valve is discontinued and was replaced by LM490. I have attached the installation instructions.
Yes, valve performance will deteriorate over time due to both wearing of parts and build-up of dirt, lime, and scale.
Replacement parts are no longer offered for the e490 valve. If you are unable to adjust or adjustment doesn't not fix hot water supply problem you can replace with the LM490 valve.

Powers Watts was also kind enough to send me the instructions for the now obsolete e490. At the bottom of the page, it has this disturbing message...

CALIFORNIA PROPOSITION 65 WARNING
WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

So this product has not only been preventing me from having the use of hot water, it may also have been giving me cancer. So I'm going to go out and buy another one? Which will itself have to be replaced in a few years? No thanks.

So if you have one of these valves installed in your house, you can't just leave it there and forget about it. You have to maintain it. Or you have to replace it every few years. For most people, this means calling a plumber - or maybe several plumbers until you manage to find one who works with these things - and dropping a couple of hundred bucks for a product which most of us don't actually need - children can regulate water temperature after their parents show them how.
 

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Old 01-21-09, 09:24 PM
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heating system mixing valve adjustment

I had a similar problem and I have Honeywell series AM mixing valves. I believe most of these valve are adjusted the same way. After unscrewing the retaining screw, back off the valve knob partially and turn in the direction that the arrow shows to make it hotter (usually counterclockwise). You will find that as you back off the knob, it will go from inability to turn it to modest resistance to no resistance at all. If you get to no resistance, you have backed it off too far and advance it a little until it grabs. I suggest adjusting by no more than 15 or 20 degrees rotation (not degrees temperature) at a time. Watch the thermometer and readjust as needed. Good luck
 
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Old 01-22-09, 01:16 PM
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I am glad I don't live where those are required.
Glad you got it figured out.
 
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Old 01-22-09, 06:21 PM
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I am glad I don't live where those are required.
Are you sure you don't? Rules and regulations within codes change all the time and there rarely is any requirement to send an individual notice to every homeowner in the jurisdiction. Some jurisdictions DO make a homeowner liable to bring certain safety features "up to current code" when selling the house and this could easily be considered such a safety feature.
 
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Old 01-22-09, 08:40 PM
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everything in Ca. causes all kinds of problems. it does not cause those problems everywhere but soon everyone will be so paranoid plumbing is gonna cost a fortune to install and repair. it is not that expensive at this time to give you a hint on what kind of pricing i am talking about. teh new faucets that we are able to install in Ca. are big and bulky and start around $200 or you can go with the regular size and nice looking faucets for around $700
 
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Old 01-23-09, 07:55 AM
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Originally Posted by furd View Post
Are you sure you don't? Rules and regulations within codes change all the time and there rarely is any requirement to send an individual notice to every homeowner in the jurisdiction. Some jurisdictions DO make a homeowner liable to bring certain safety features "up to current code" when selling the house and this could easily be considered such a safety feature.
I am sure.
So far here we are still allowed to think and do for ourselves, at least when it comes to temp. regulators on our hot water.
Nursing homes or course have to have them.
 
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Old 01-31-09, 05:28 AM
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The REASON FOR REQUIRING THERMOSTATIC MIXING VALVES is to prevent legionaires disease, which is a potentially deadly infection caused by the legionella bacterium. This bacteria loves to reproduce in water at about 120 degree temperatures. (Where an unprotected water heater is usually set.
Welcome To Cash Acme
The idea is to turn the water heater up to 140 degrees which kills the bacteria. (actually about 134 to 137 kills them. The problem is that these temperatures are too hot for people to shower or bathe in. Thus the need for the tempering valve, to TEMPER it back down to 120 into the pipes. Some people have a tee off before the mixing valve to run 140 degree water to dishwashers and washing machines, but all taps should be after the valve unless you are a lab or for food processing machine washdown, which is usually even hotter than 140.

Sometimes they clog with lime scale. I would plumb in a bypass that allows you to temporarily take it out of service to delime it (vinegar or CLR) but while you are doing that be aware of the scalding danger. You could turn your heater down to 120 for the day that it will take to flush out the valve, but remember to turn it back up when you're done.

You could make it a part of your annual maintenance routine, and delime it out while you are also manually draining sediment from your water tank (to help it last longer). You are doing that occasionally aren't you? Many manufacturers suggest every three months turning off the power to the heater and turning off the cold supply. Then draining about a quarter of a tank through the bottom drain, through a hose to a floor drain. Then turn the cold supply back on and refill the tank BEFORE turning the power back on or you will blow a top element. This procedure drains off some of the sediment that eventually will fill a tank above the bottom element and perhaps be the cause of your original problem. (NOT THE MIXING VALVE AT ALL)

Sometimes when the sediment has built up to above the lower element, that element will fry, so you are now only heating with one element. You will get hot (or warm) for awhile, then it will get colder, and if you turn the temp up you might get is back up to lukewarm for awhile before it gets cold again. That is a sure sign that your tank is filled above the bottom element, It can be rehabilitated at about half the price of a new tank. You might get a few more years out of it by removing some of the sediment and replacing the element. Look up DELIMING in the Yellow pages. It used to be a stinky operation with chemical etc., but most operators do it with distilled water jets though a pressure wand, inserted through the drain hole at the bottom of the tank. They blow off the accumulated lime scale and drain it out, then usually replace the lower element. About $200 CDN with the element. Or you can go to the dealer and buy a new one, for at least $400 (40 gal) by the time you pay tax and buy all the little incidentals like a NEW THERMOSTATIC MIXING VALVE.
 

Last edited by wolf6656; 01-31-09 at 06:24 AM. Reason: add link
  #25  
Old 01-31-09, 05:52 AM
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Of course, I just noticed you are in Toronto. I never had much of a lime problem when I lived there, not like here in Kitchener, where you can almost watch it form.

Still the valves can also clog with sediment. Plumber's should run water through any upstream piping before putting the valve in service, but time is money and it doesn't ALWAYS get done.

The TEMPERING VALVES I have seen HAVE SEDIMENT SCREENS in the incoming hot and cold unions which may need to be cleaned out from time to time. Solder pieces, pieces of copper from undeburred pipe, sand, silt, rust etc, can all be introduced into your water system, and clog things like tempering valves. Your problem may be as simple as a clogged sediment screen on the hot side, of the tempering valve.
Also check upstream of the tempering valve for a shutoff between it and the heater. Maybe this is not open all the way causing throttling of the hot line.
Some plumbers in deluxe installations will install dial thermometers before and after, or at least after the mixing valve to check the temperature. This should really be done but isn't done enough.
http://www.watts.com/pdf/1915905.pdf

Here is a link to a pdf from Watts which is actually the same company as Powers (your pictured valve). There is a trouble shooting page.
 

Last edited by wolf6656; 01-31-09 at 06:20 AM. Reason: add link
  #26  
Old 01-31-09, 09:25 AM
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Hi wolf6656.

Thanks for going to the trouble to list all this information.

However, the problem has already been solved by removing the mixing valve and reconnecting the pipes the way they should go in the first place. Now the water is hot and there is nothing attached to the pipes which may prevent hot water from reaching the taps in the house; now, or in the future. By removing one level of unnecessary complexity, the problem is gone and will not return. There is no need to install a replacement valve, or pay hundreds of dollars to fix something or install something else, or worry about the problem coming back in the future and having to waste time diagnosing it, working on it or having somebody come in here and fix the problem partially, or not at all.

There were no filters or screens on the valve which I removed. I did clean it by soaking it in vinegar for a few days but did not see any sediment or dirt in the valve when I removed it.
By the time it was clean, I had already soldered the pipes back together and was very happy with having hot water in this house for the first time. I had no interest in putting back this valve, which I don't actually require.

I am comfortable adjusting the temperature of any water I might use manually. I have been doing this for my entire life. I don't need a device to do it for me and prevent me from choosing the temperature I want/need while also introducing a level of complexity that was, to be perfectly honest, creating more problems than it was solving.

I'm never going to install another valve in this house. If it is required by the code, and I am forced to install one, I'll remove it as soon as it is inspected. When I bought this house, nothing met the code. Nothing at all. I wasn't able to sue anybody or force the previous owner to fix anything. He didn't care and neither did the government.

When I'm done bringing things up to standard or beyond, this house will be vastly safer and more efficient than it was before. But I refuse to use one of these valves because it didn't help me in any way - it made things worse, not better.

As for the Legionnaire's Disease, that's interesting and thanks for sharing that. I didn't know about it.

But anyways, both elements on the water heater are set at the halfway point between 150 and 125 F; or 137.5 (59C), so that should kill them. I set them at that temperature. The manufacturer's settings were below that. And it's a rental. Like I mentioned before, Enbridge has been out here several times and they left the temperature well below that. I only raised it after realizing none of them had solved the problem of having no hot water. So neither the manufacturer or the rental company seem particularly concerned with preventing Legionnaire's Disease. I'm the only one who has done anything to prevent it from occurring here.

And speaking of bacteria and hygiene, I think it is necessary to have hot water available for cleaning to kill other bacteria besides the ones causing Legionnaire's. So for that reason alone, I do not wish to have any mixing valves installed here in the future.

Anyways, you've added some important information to the thread and I hope anyone else who's not getting correct answers from their plumber or hot water rental company will find some possible solutions here.
 
  #27  
Old 02-01-09, 06:02 PM
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Originally Posted by doublezero View Post
CALIFORNIA PROPOSITION 65 WARNING
WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.


I see you are not from Calif, so you may not be familiar with the prop 65 warning, which appears on everything! From any kind of plumbing product made of brass, to candy wrappers!

But hold on to your hat, Kemosabe, because these lead laws are going national in the US , soon!
 
  #28  
Old 08-16-09, 10:07 PM
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I should also add the primary use of a mixing valve.
1- to act as a safety precaution against scalding in the event that a water tank would accidentally reach dangerous temperatures.
2- to allow the home owner to increase water tank temp over 60 degrees celsius which kills the legionella bacteria known as Legionella pneumophila legionary disease
3- to increase hot water temp, resulting in less hot water used in your tank, which increase the duration of hot water use and reduce utility cost.
 
  #29  
Old 08-16-09, 10:34 PM
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Solarchoice,

Thanks, but I removed the mixing valve and successfully soldered the pipes back together in the correct way back in January. Since then, I have been happy with the hot water temperature in here. There have been no problems with it and the chances are good that there won't be unless I install another mixing valve.
 
  #30  
Old 12-29-09, 03:57 PM
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Water Temperature Control Valve

Put a meat thermometer under the kitchen / bath hot water tap and note the temp. In my case it approx 110 , was just below 120F.
Check the label on the temp control valve and note the rotation which provides warmer water , ( a red arrow).
Remove the center of the label from the temperature control valve , and remove the star screw.
Remove the plastic control knob.
With a suitable wrench , Relax - adjust the outer nut by approx 1/4 turn .
Put the Plastic knob back on aligning the inner slot with the metal tab as before.
Twist with you fingers until the knob rotaes (dragging the inner metal tab with it) .
Use the meat thermometer in the kitchen faucet again . If the water temp improves to 120 , perhaps 123 . Put the screw back in place and be happy.
If there is no change to measured temperature, check the water temperature directly in the tank.
The method may require tapping the valve with a small screw driver handle to remove lime deposits.
Also keep in mind that the control valve should be mounted 1 foot below the hot water tank outlet per
http://www.watts.com/pdf/1915905.pdf
 
  #31  
Old 08-01-10, 02:43 PM
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Simple way to defeat mixing valve

I recently moved into new construction with a mixing valve that only allows 120F out, nowhere near hot enough for us. Since it mixes a lot of cold water with a small amount of hot water I reversed the hot and cold sides of the valve. I removed the valve, flipped it over, and reinstalled with inlets reversed. Now the output is nice and hot.
 
  #32  
Old 01-19-11, 12:32 PM
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Great suggestion

Originally Posted by DesertRatR View Post
I recently moved into new construction with a mixing valve that only allows 120F out, nowhere near hot enough for us. Since it mixes a lot of cold water with a small amount of hot water I reversed the hot and cold sides of the valve. I removed the valve, flipped it over, and reinstalled with inlets reversed. Now the output is nice and hot.
Took your advice and flipped the mixing valve, worked like a charm. Finally have hot water at my taps! Thanks!
 
  #33  
Old 01-19-11, 01:08 PM
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If 120 isn't hot enough..other issues should be addressed. Reversing a CORRECTLY installed and CORRECTLY operating component of a plumbing system is defeating the purpose.
 
  #34  
Old 05-30-11, 09:04 AM
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This thread is the first result from googling "removing mixing valve" so I guess it is a common problem for quite some people.

Thanks DesertRatR for the hint and I will try it first thing tonight when I get home.

I went to a homedepot this morning before work to try get a replacement for the valve but it ran out stock and I was pointed to a far way store since the ones around ran out that thing as well.

I read through and quite confused over the part of the valve would help get rid of the Legionnaire's Disease. To my knowledge, the valve is mixing cold water with the boiled water to reduce the temp. The water in the tank might be with no bacterial, but how about the cold water which will be mixed together?
 
  #35  
Old 05-30-11, 09:41 AM
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Doing a search for "Legionnaire's Disease and water heaters" will bring up a lot of info....some simple and some more complex. Basically the WH set at a lower temp provides ideal conditions.

"Q. What water conditions are best for growth of the organism?

A. Warm, stagnant water provides ideal conditions for growth. At temperatures between 20C-50C (68-122F) the organism can multiply. Temperatures of 32C-40C (90-105F) are ideal for growth. Rust (iron), scale, and the presence of other microorganisms can also promote the growth of LDB."

From here... Legionnaires' Disease eTool: Facts and FAQs
 
  #36  
Old 05-30-11, 10:22 AM
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Thx Gungus45. I am more clear on that part now.

The high temp in the tank is to prevent that kinda bacterial grows under the ideal temperature if there is any from the fresh cold water.
 
  #37  
Old 06-06-11, 10:22 AM
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An update.

Last week I did the cold/hot swap (courtesy of DesertRatR) and I got back the hot water with normal pressure. I could even do the temp fine tune like the regular one which hot hot water in the tank and less hot water out of the valve. I guessed the hot water side might be not sensitive enough or clogged by mineral already. Hopefully next time I did the swap again the original hot entry's clogging would be washed out by the cold water already.
 
 

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