How to Make the Most of Continuous Flow Hot Water System

Do you have issues where you can’t wash up and have a shower at the same time?

Or do you have a family bathroom and ensuite but still have to stagger your showers? There’s a great option for you. You can set up a larger Continuous Flow Hot Water System. So you can have great pressure, fewer pressure fluctuations, and then be able to run two showers at the same time and make it super safe for kids and the elderly.

Worry not! In this video, we’ll explain how to do that to get the maximum result correctly.

And the plus side is, we draw it all for you.

So you can’t run two showers at the same time.

Here’s a great option for you.

You can install a 20 or 26 Continuous Flow Hot Water System. It is very important to set it up correctly, so it works to its maximum potential.

First of all

Make sure that the water main supplying your HWS system is 20 mm, not 15mm.

Then make sure the hot water outlet pipe is also 20 mm.

So now we’ll explain to you about the manifold system.

It’ll be easier if we draw it for you, so make sure you watch the video.

So you have an existing house or building a new house and have made the decision to install a 20 or 26 Continuous Flow Hot Water System.

We’re guessing you will need to supply hot water to your kitchen, laundry, main bathroom, and of course your ensuite.

Now, your Gas Continuous Flow Hot Water System will need to have a larger 20mm diameter water pipe supplying it.

So it makes sense that you will also need a larger diameter pipe exiting your hot water system to pipe the hot water to all the fixtures.

Your plumber will usually run the larger hot main throughout your whole house, then branch off in smaller pipes to feed your kitchen, laundry, main bathroom and your ensuite. Which will work great and ensure minimal pressure loss when two taps are used at the same time.

Except, there is one big problem.

Just say you wanted to wash your face with hot water. You would have to flush out the cooled water from the entire large hot water main before any lovely warm water touches your face.

Wouldn’t it be better if you only had to flush out the cooled water from a smaller diameter pipe?

Yes, but then you would have some pressure loss when using two taps at the same time.

Here is the solution.

Still have a larger diameter pipe coming out of your hot system, but keep it short as possible and then run smaller diameter pipes individually to each area.

Now you will enjoy great water pressure and will only be flushing out a small amount of cooled water before the tap will run nice and warm.

It looks so simple on a white board, but will it work in the real world?

So now we will show you how we retrofitted a 26 Continuous Flow HWS to this beautiful three-bathroom Italian mansion.

Now this is the HWS that they have at the moment. A massive 170 litre inefficient gas storage.

They did have a Temp Valve installed, but they got rid of that, obviously not too concerned about scolding hot water.

The previous plumber was told to put the biggest HWS possible and never gave the owners the option of maybe installing a Continuous Flow HWS.

It would be easy because the gas meter box is just on the other side of the fence.

Now this entire mansion has a 15mm hot water main, so it would’ve been fine to install a 16 HWS in this situation.

But there would be some loss of pressure when two taps were on at the same time.

We installed a 26 Continuous Flow HWS at this owner’s last house and they loved it. So they have asked us to retrofit this house and install manifold system as well as some temperature keypad so they can use this hot water system to its full potential.

The Process

First, we need to test the gas main then disconnect the old hot water system. Pull up some paving to locate the 20mm water main and run the larger size pipe up to the new HWS location.

Then we will need to run a new larger gas main directly to supply the new HWS from the meter box on the other side of the wall.

Next, we need to pull up the paving to try and find where the hot water main branches off to each bathroom and to the laundry and kitchen sink. So after we have manufactured the manifold, we can then run separate lines to each of the bathroom and the laundry and kitchen.

Now we have found the separate water mains that go to the kitchen laundry and to the separate bathrooms and have run individual smaller main to each one of them.

As you can see, we have installed a new large water and gas mains supplying the new continuous flow hot water system.

Now why have we installed it so high? Because there is an A/C unit going underneath it.

And this is the manifold.

See how all the lines from each bathroom, kitchen, and laundry branch off the larger pipe. So this setup is fantastic for minimising pressure drop.

So you will be able to run two showers at the same time with the set up.

The only thing left to do is set up the wireless controller and the transmitter, and get the unit up and running.

But that will be done on another video you can check out on our website.

So if you’re building a new house or would like to retrofit your existing house with a Continuous Flow Hot Water System with a manifold, and you live in or near the Shire Kalamunda, give us a call. We’ll be happy to help.

Have you already got a Rinnai but still not enough hot water? Make sure you clean the filter.