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Ideal Isar Boilers: How to Get a Reliable Replacement

Nick Geary
By: Nick Geary
Updated: 24th October 2023

ideal heating

You won’t find many better boilers than those made by Ideal Heating. However, in the mid-2000s, they were asked by the government to make a range of combination (combi) boilers on the cheap.

These boilers weren't their best work.

They were made to meet a deadline so that they could be quickly fitted into homes that needed them. Unsurprisingly, they're no longer being made and those that were fitted haven't stood the test of time.

Many owners of Isar boilers have found themselves running into a number of problems over the years. You might be considering repairing your boiler, but more often than not it’s more worthwhile to just get a brand new boiler. New boilers will have a higher energy efficiency and can help to reduce your annual heating bills and your carbon footprint.

We can easily help you replace your Ideal Isar boiler with one of the top boilers on the market at a fair and competitive price. It all starts with requesting quotes from highly rated and trusted heating engineers.

With Boiler Guide’s network of heating engineers, you’re guaranteed to get up to 3 competitively priced quotes all for free and without any obligations. To start getting free quotes to compare, simply fill in a 1-minute form by clicking the button below.

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The Ideal Isar combi boiler range

There were three combi boilers in the Ideal Isar range: the HE24, HE30 and HE35. All of which had a central heating output rating of 23.4 kW (in non-condensing mode) making them a great choice for homes with around 11-12 radiators (2 kW per radiator).

The output rating is a measurement of the boiler’s power and is often known as the size of the boiler. You can read more about that in our ‘What size boiler do I need?’ guide.

Ideal Isar HE24 HE30 HE35
CH output rating (Condensing) 25.1 kW
CH output rating (Non-condensing) 23.4 kW
DHW output rating 23.4 kW 29.3 kW 35.2 kW
Domestic hot water flow rate (35C) 9.6 l/min 12 l/min 14.4 l/min
Seasonal efficiency (SEDBUK) 90.1%

CH = Central Heating. DHW = Domestic Hot Water.
Since these boilers were manufactured, the SEDBUK efficiency rating has been replaced by the Energy related Products Directive (ErP). So, they're not likely to be as efficient as the specifications suggest – especially as they were installed 10+ years ago.

Why you should replace an Ideal Isar

Chances are your Isar was installed more than 10 years ago which means you should really be thinking about a replacement boiler. It's recommended to replace even the most high-end boiler after 10-15 years and the Isar boilers don't fall into this category.

Looking for a similar boiler?

If your heating and hot water demands haven't changed since the Ideal Isar was installed (your home has the same number of radiators and bathrooms) then you can get a combi with the same output.

Ideal has a number of reliable and efficient boiler ranges including the Logic Max and Logic Plus. These boilers have very similar output ratings to the Ideal Isar boilers but are much more efficient and come with lengthy warranties.

Ideal Logic Max

This is Ideal's most efficient and reliable range of combi boilers.

They're also certified to run on a 20% hydrogen blend which is great news if hydrogen is added to the gas network to help lower carbon emissions.

Ideal Logic Max C24 C30 C35
CH output rating 24.2 kW
DHW output rating 24.2 kW 30.3 kW 35.3 kW
Flow rate 9.9 l/min 12.4 l/min 14.5 l/min
Efficiency 94%
Warranty 10 years

Ideal Logic Plus

The Logic Plus range came out before the Logic Max range but these combi boilers still hold their own.

Ideal Logic Plus C24 C30 C35
CH output rating 24.2 kW
DHW output rating 24.2 kW 30.3 kW 35.3 kW
Flow rate 9.9 l/min 12.4 l/min 14.5 l/min
Efficiency 94%
Warranty 7 years

Do you need a bigger boiler?

You'll need a more powerful boiler if your heating and hot water demands have increased since your Ideal Isar was installed. By that, we mean more radiators or a new bathroom.

Here are some of Ideals more powerful combi boilers:

Vogue Max C40 GEN2 C40
CH output rating 32 kW 32 kW
DHW output rating 40 kW 40 kW
Flow rate 16.4 l/min 16.4 l/min
Efficiency 93% 93%
Warranty 12 years 10 years

Two or more bathrooms? Then go for a system boiler

As a combi boiler, the Ideal gives your home heating and hot water on demand. This means they can struggle to meet demand for hot water from two water outlets at the same time. So, if you have two or more bathrooms, then a system boiler is the better option.

Now, system boiler sizing (that's the output rating) works a little differently to combi boilers. The table below shows the output rating you need based on the number of radiators in your home.

Radiators Recommended system boiler size
Up to 10 9-18 kW
10-15 18-26 kW
15-20 27-40 kW

The Ideal Vogue Max range of system boilers includes a number of models with different outputs.

Ideal Vogue Max S15 S18 S26 S32
CH output rating 15 kW 18 kW 26 kW 32 kW
Efficiency 92% 93% 93% 93%
Warranty 10 years

System boilers don't have a hot water output rating or flow rate. This is because domestic hot water is stored in a hot water cylinder and sent to taps from there. Combi boilers do have a flow rate. The combi boiler flow rates can go up to 20+ liters per minute.

Visit our Boiler Comparison Tool to compare all Ideal system boilers. Once you’ve found the right boiler for your home, take the next step by completing our quick and simple online form to help you find installers in your local area and get quotes to compare. Any quotes you receive are free and come with no obligations to accept.

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How much do new Ideal boilers cost?

Most Ideal combi boilers are priced around the £1,000 mark. Then around £1,5000 – £2,000 with the installation costs added on top. But this will all vary depending on the type of boiler, model and how many quotes you compare for the installation.

Ideal combi boiler prices

Logic Plus combi boilers tend to come with the lowest price tag. But if you spend extra to get a Logic Max or Vogue Max, you'll be covered by a longer warranty (10-12 years compared to 7).

Cost of boiler Installation costs Total
Logic Max combi £968 – £1,156 £500 – £1,000 £1,468 – £2,156
Logic Plus combi £847 – £1,039 £500 – £1,000 £1,347 – £2,039
Vogue Max combi £1,089 – £1,323 £500 – £1,000 £1,589 – £2,323

Ideal system boiler prices

Alongside the system boiler, you'll also need an unvented hot water cylinder. Hot water cylinders can cost can range from £300 up to £2,000 depending on the model and its capacity. That's without installation.

Cost of boiler Installation costs Total
Vogue Max system £1,030 – £1,258 £500 – £1,000 £1,530 – £2,258

Compare the Best Unvented Cylinders to go with your new system boiler.

Find an installer to replace your Ideal Isar

You'll need a Gas Safe registered engineer to replace your old Ideal Isar boiler. This means that they're listed on the Gas Safe Register. Making them the only people qualified to replace gas boilers.

You can get free quotes from as many as 3 Gas Safe registered engineers in your area by letting us know that you need a new boiler. To do that, you'll need to complete our simple online form – it takes less than a minute.

Soon after you've done that, Gas Safe registered engineers in your area will be in touch to arrange a quote for your new boiler.

Click the button below to start the form and be on your way to getting tailored quotes.

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4.6/5 out of 23,524 reviews

1,8 million quotes provided in 10 years

See more reviews:

Nick Geary

About the author

Nick Geary

Nick has a wide range of experience writing about conventional and renewable heating solutions, and is always increasing his knowledge by researching any new heating technologies on the horizon.

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