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Refuse 11-08-2009 07:18 PM

Mixing Valve
I have been having a problem with my mixing valve. I have lost hot water for the second time in two weeks. I called in a plumber and they fixed it in minutes by turning the screw on the mixing valve counter clockwise. I have been trying all night with no luck. The other thing that the plumber did was remove any air from my pipes. Tried that too. Not sure if I did this right. How do I reset the water tank and mixing valve? How do I correctly remove all air from my lines?

Nestor_Kelebay 11-09-2009 12:28 AM

If you don't get any response in here, it's probably because people won't be familiar with the "mixing valve" and "air in the lines" you're referring to.

The only place where I know a mixing valve is used in some houses is to mix both hot and cold water to supply warm water to the toilet tank. That's done to prevent condensation on the toilet tank. Is that what your mixing valve is used for? If not, can you let us know what it is, where it is and what it does. So far as I know, there's no water mixing valves used on hot water heating systems.

Air in your water pipes is only a concern if you're talking about a hot water heating system. That is, the heating system that heats your house in winter. If you heat water meant for cooking, cleaning and bathing in a water heater, then you're ALWAYS going to get bubbles of oxygen gas collecting in the hot water supply piping to your faucets, but those oxygen gas bubbles do no harm whatsoever. Cold water can contain more oxygen gas in solution than hot water, so as you heat cold water in your water heater, oxygen gas can be driven out of solution and will collect as bubbles at the top of your water heater or in your hot water supply piping. If you turn on your hot water faucet, you will often see/hear a small blast of gas coming out of the spout with the water. The gas coming out is oxygen gas that was driven out of solution from the cold water when it was heated in the water heater. You simply run your hot water faucet to remove it from your hot water supply piping.

So, we're not sure if you're talking about domestic water supply piping or a hot water heating system. A "mixing valve" could also mean a tub and shower faucet cuz no one showers in pure hot or cold water, and those things do have anti-scald mechanisms on them that do have adjustment screws. Suffice it to say that we're not really sure of what you're referring to by "mixing valve" and "air in the lines", and until we're sure, we can only guess at the problem.

Could you please clarify. Thanks.

Refuse 11-09-2009 06:15 AM

Mixing Valve Photo
I do have a gas hot water tank.

Please take a look at this link:
Mixing Valve?

This is my mixing valve and a diagram of how these things work. Or in my case not work. I hope this helps.

The water supply is going to my shower, taps, dishwasher, you name it.

Thank you.

Refuse 11-09-2009 06:18 AM

I do have a gas hot water tank. My mixing valve is used on my hot water tank. The tank is 1yr old and out of warranty.

Please take a look at this link:
Mixing Valve?

This is my mixing valve and a diagram of how these things work. Or in my case not work. I hope this helps.

The water supply is going to my shower, taps, dishwasher, you name it.

Thank you.

travelover 11-09-2009 06:28 AM

I'm thinking that the OP is referring to the anti-scald valve in the shower. When I first installed mine, tiny particles of grit got into the mechanism and it would not go to the full hot internal position until I took it apart and cleaned it thoroughly - twice.

The outer handle doesn't directly control the mix of hot and cold water - it is overridden by an internal temperature sensing control. This control has tight clearances that can be jammed by scale and sand in the water.

Refuse 11-09-2009 06:56 AM

Thank you, I was told by the plumber that it was the anti-scald valve, but he was messing around with that component on the webpage.

How do I go about fixing this. I believe that you are correct.

Refuse 11-09-2009 07:24 AM

Mixing Vlave
This is not just the shower but all taps.

Nestor_Kelebay 11-09-2009 10:53 AM

Honeywell is really good about providing the technical literature that comes with (or came with) their products online.

If you e-mail Honeywell at their "Support and Contact" link on the web page you provided (or phone their customer service 1-800 phone number) and ask where you can find the original literature that came with your model of mixing valve, they should be able to tell you where to find and download it online. That literature will explain how to adjust the valve, how to troubleshoot problems with it, and probably how to take the valve apart to clean it and how to subsequently reassemble it. A plumber would need to know all that if there were problems with the valve after he installed it.

Refuse 11-09-2009 11:43 AM

Sorry. It wasn't Honeywell. I just found that online. It was Bradford White. I will try to find a manual.

Refuse 11-09-2009 04:27 PM

Mixing Valve
This is not in the manual. Just checked. This is an external component. Apparently this part was installed because plumbers have been sued installing water tanks and leaving them in the wrong position. Scalding kids = lawsuit. Really annoying. And nobody knows how to fix this, remove it or eliminate it.

Time for the plumber I guess?

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