I want to combine water from a hot and cold spigot to a single hose. What is the fitting called that does this?

The fittings I have seen only split a single water source into two different branches, not the other way around.

  • 1
    if you reverse it it will do what you want
    – Traveler
    Commented Mar 11, 2023 at 22:37
  • Turn it upside down. They work both ways. Might need hose and/or adapters to make it fit.
    – crip659
    Commented Mar 11, 2023 at 22:37
  • 1
    Do check that what you are trying to do is legal in your country. Because in mine, mixing hot and cold in that manner would be illegal unless the cold water was coming from your own tank.
    – Simon B
    Commented Mar 11, 2023 at 23:20
  • 1
    @SimonB Can you expand on your comment. Because this is what happens in every sink faucet/tap, except as a tee instead of a Y.
    – crip659
    Commented Mar 11, 2023 at 23:57
  • 2
    @crip659 Here in the UK, there are rules to prevent accidentally back-feeding your hot water into the public water supply. All the mixer taps in my house have concentric pipes in the spout, The hot and cold water doesn't actually mix until it has left the tap. An alternative would be a one-way valve to prevent backfeeding.
    – Simon B
    Commented Mar 12, 2023 at 16:48

2 Answers 2


Conceptually, as noted in another answer, this is simply a Y in reverse. The problem is that you normally want to control how much hot and how much cold. My old washing machine three temperature settings (with various combinations of them for wash vs. rinse):

  • Hot = 100% hot
  • Cold = 100% cold
  • Warm = 100% hot + 100% cold

The warm isn't mixing in the pipe or valve. It simply opens up both hot and cold valves at the same time and they both pour into the tub. What temperature is that water? If the pressure is the same (it should be the same, but due to a water heater in the middle on the hot supply, they might not be exactly the same), that could be many different things:

  • 40F + 120F = 80F
  • 40F + 140F = 90F
  • 60F + 120F = 90F
  • 60F + 140F = 100F


For typical clothes washing, it doesn't usually matter much. For other things, it might matter a lot. Which is why faucets (kitchen, bath, laundry, etc.) either have separate hot and cold handles or a single handle that adjusts the mixture of hot and cold. And for automated things where the temperature matters, either the device will have a thermostat to control the mixing, a way to stop it from getting too hot or a way to heat it up if it is too cold (e.g., for a dishwasher).

There is an additional complication with the described situation, which is that you need to have some sort of check valve or backflow preventer to make sure that you don't get flow from the cold line into the hot line or vice versa. That isn't a problem normally with a faucet or washing machine but could be with a hose attached as described.

But in the end, if you really want to have an arbitrary setting (not adapting based on incoming water temperatures), yes such devices exist. In a quick search, I found as one example this model from Home Depot:

mixing valve

It has 3 connections - hot inlet, cold inlet, mixed outlet. It has check valves on the hot and cold inlets. It is adjustable, so you can do something other than an exact 50/50.

Come to think of it, based on some Q&A on the Home Depot page, this type of thing may be how public bathrooms set the temperature for automatic faucets. I never thought about it before, but they can't do pure cold because people would complain, and they can't do pure hot because it would be too hot. This is how you get to the goldilocks temperature. But not perfect - which makes sense because it is just a simple setting and not a real thermostatic mixing.

  • Unless you have one of those magical Y splitter with two valves on it where you can control how much you mix of each and that way control the temperature
    – Traveler
    Commented Mar 12, 2023 at 2:49

All of the following do what you want

They are either one in and 2 out

or if you reveres the connection then it is two in and one out.

Additionally they have independent flow valves so you can control the mixing of hot and cold.

y splitter

There are adapters for Male/Female and Female/Male

  • you cannot revers the connection. The inlet is female and the outlets are male.
    – RMDman
    Commented Mar 12, 2023 at 0:04
  • 2
    @RMDman did you hear there are adapters for that
    – Traveler
    Commented Mar 12, 2023 at 0:41
  • That info was not in your answer. the Y is plentiful most anywhere, even grocery stores, but I have not seen an adapter yet.
    – RMDman
    Commented Mar 12, 2023 at 1:54
  • @RMDman I newer go to grocery store for my plumbing needs, do you ?
    – Traveler
    Commented Mar 12, 2023 at 2:37
  • 1
    Adapters should be available in any garden supply shop and most hardware stores, plus home centers which have some of both. It's still not a great solution; see the answer by manassehkatz-Moving 2 Codidact for details of why and how to avoid those issues .
    – keshlam
    Commented Mar 12, 2023 at 2:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.