Use your tank without the app

You do not need the Mixergy app for everyday hot water control. Use the Mixergy Gauge, the slim black panel with lights and buttons on the tank, to check how much hot water is ready and ask the tank to heat more.

The gauge continues to work if you do not have the app or your tank is offline. Leave the tank switched on so it can heat water when needed.

What the gauge shows

The gauge uses buttons, symbols and coloured lights. These show how much hot water is ready, how much the tank is working towards and whether it is connected to the internet.

1. Power button

The round button at the top switches the tank’s controls on or off when held.

2. Wi-Fi symbol

A blue Wi-Fi symbol means the tank is connected to the internet. A white Wi-Fi symbol means it is offline. You can still use the gauge when it is offline.

3. Blue lights

Blue lights show how much of the usable water in the tank is still cold. For everyday use, focus on the red lights showing hot water that is ready and the green lights showing the amount being heated.

4. Red lights

Red lights show the amount of hot water ready to use. More red lights mean more hot water is available.

• You don’t need all ten lights to be red. Five red lights mean about half the tank’s hot-water capacity is available. That may be exactly the amount you asked it to heat and enough for your needs.
• Fewer than ten red lights does not mean heating is unfinished. The tank needs to heat more only when you ask for a higher amount or its heating controls request it.
• One light does not equal a set number of showers or baths. How long the hot water lasts depends on your tank size and how much water you use.

5. Green lights

Green lights show additional water the tank has been asked to heat. That extra amount is not ready yet. The tank may be heating it or waiting for heat to be available. As the water becomes ready, those lights turn red.

• For example, five red lights with no green lights can mean the tank has finished heating to its requested level. Five red lights with two green lights mean five lights’ worth is ready, with more still requested.

6. Up arrow

Press the up arrow to ask the tank to heat more water. Each press adds one light, or about one tenth of the tank’s usable hot-water capacity.

7. Down arrow

Press the down arrow if you have selected more hot water than you need. Each press removes one green target light. It cannot make water that is already hot turn cold.

How to check how much hot water you have

Look at the vertical row of lights and count the red lights. More red lights mean more hot water is ready. If there are no red lights, the tank may be cold or still heating.

You will learn what is normal for your home. Start by checking the lights before a usual shower or bath, then look again afterwards. This helps you understand how much your household normally uses without relying on a fixed estimate.

How to ask the tank to heat more water

If you need more hot water:

1. Check how many red lights are showing.
2. Press the up arrow once to add one green light.
3. Press it again for each additional light you want the tank to heat.
4. Wait while the green lights turn red.
5. If you selected too much, press the down arrow to remove green target lights.

What if the lights do not change?

• Check that the tank's normal visible power switch is on, if it is safe to reach.
• Wait a moment after pressing an arrow and check whether a green light appears.
• If the tank is already showing ten lights, you cannot select a higher target.
• The tank may occasionally run an automatic cleansing cycle, which heats all the usable water to help keep it safe. During this cycle, the tank may heat to full and Boost may be temporarily unavailable.

If there are still no lights, or the green lights do not turn red after allowing time to heat, use the relevant no-hot-water or Boost troubleshooting guide.

What the gauge does not tell you

The Gauge gives you the controls needed for everyday hot-water use. If you also use the app, you can see more detail, set schedules, add your energy tariff, review your usage and use Boost when you are away from the tank.

Heat-source selection and account transfer are separate setup tasks. Do not reset the account or change advanced settings just to check or boost hot water. If you rent, ask your landlord or housing provider before resetting anything.

Common questions

Do I need Wi-Fi to use the gauge?

No. The arrows and level lights work without an internet connection.

Does one light equal one shower?

No. One light is about one tenth of your tank’s usable hot-water capacity, but the amount a shower uses varies between homes.

Why are some lights green?

They show the new target you have selected. They turn red as that water becomes ready to use.

Can I reduce the amount after pressing the up arrow?

Yes. Press the down arrow to remove green target lights. Hot water that is already ready will stay hot.

Should I switch the tank off after use?

No. Leave it switched on so the tank can operate normally and prepare hot water when needed.

What if the Wi-Fi symbol is white?

The tank is offline, but the gauge still works. Reconnect it if you want to use live app features.

Related guides

The Mixergy Gauge

Tank won’t connect or shows offline

No hot water

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