Worcester 30Si Compact Combi Boiler Review (Buying Guide)

In this 5-minute review we’re going to cover the Worcester 30Si Compact in detail, and explain the cheapest places to get it installed.

But first, the answer to the most frequently asked question we get:

Why Not Save £250 And Buy The Greenstar 30i Instead?

The 25i and 30i are two of the most popular boilers in the Worcester combi range. For standard 2-4 bedroom semi detached properties needing a combi, they’re also the cheapest.

The biggest difference between the I and Si, is the physical size of the boiler. It takes lots of R&D to fit the same technology into a smaller package, so the 25i is cheaper than the 25Si Compact. Likewise, the 30i is cheaper than the 30Si Compact.

So, why not save some cash?

It all boils down to this; do you need to fit your new boiler in a kitchen cupboard, or similar small space?

If your answer is yes, you’ll need the 30Si Compact over the standard 30i.

If your answer is no, you can save money by installing the 30i instead. You can read our review of the 30i here.

What Size Property Is The Worcester 30Si Compact Suitable For?

The central heating output of the 30Si Compact is 24kw, the same as the 25Si Compact. The main difference between the two is the hot water flow rate. The 25Si only hits 8.9 litres per minute, whereas the 30Si produces a much higher 10.7 litres per minute.

Typically, you’d expect the 25Si to be fitted in small properties such as 1-3 bedroom flats, or a small 2 bedroom terraced. The 30Si is going to be fitted in a 3 bedroomed semi, although in some scenarios, it may work in a 4 bed.

It’s important to note that whilst the output of the 30Si is reasonable, the output of combi boilers is limited.

You can use this boiler size calculator to determine whether the 30Si Compact is the most suitable boiler for your property.

How Much Does The Worcester 30Si Cost?

There’s no doubt that Worcester Bosch are up there with the more expensive boilers on the market; comparable in price to brands like Baxi, Potterton and Vaillant.

Using the boiler size calculator we mentioned above, we got a fixed price quote of £2,335, and that’s a great deal. It’s worth mentioning that prices will vary depending on what options you choose on the clickable form.

Worcester Bosch Greenstar Si Compact 30kW

In comparison, the quote we got for 30i using the same options was £1,970. So, if you don’t need to tuck your boiler away in a small cupboard, you could save £250 by going for the 30i, rather than the 30Si Compact.

Where’s The Cheapest Place To Get A 30Si Compact Installed?

For most brands, the best deal on installation prices comes from local installers; big nationals struggle to compete with them on price.

In the case of Worcester boilers, HEATABLE tend to be the cheapest.

Why? Because they concentrate on technology more than on salespeople, it’s fair to say HEATABLE get boilers like the 30Si Compact at preferential rates, so it’s hard for the smaller installers to compete on price.

Also, due to the quote process being online, that helps to remove the need for a site visit and sales person, reducing costs further.

How Long Is The Warranty?

We’re big advocates of big warranties. At the end of the day, a boiler manufacturer offering a 2-year warranty on a product, is hinting their appliance isn’t going to stand the test of time (*opinion).

You’ll find the price differences between boilers with 2, 5, 7 and 10 years warranty isn’t huge. And, as the boiler itself only makes up around 50% of the overall installation cost, we’d always be heading for boilers with the longest warranty.

That means completely avoiding boilers with a 2-year warranty. 5-years would be our bottom line, with anything higher being preferable.

The Worcester 30Si Compact? Using an accredited installer like HEATABLE, you’ll get a huge 10-year warranty.

Happy days!

Does It Have Frost Protection?

If you’ve been shopping around and reading reviews of some of the best boilers on the market, you’ll notice a lot of boilers and/or thermostats offering “frost protection”, and the likes.

The Worcester 30Si Compact has something much better than frost protection; the Condensesure Syphon.

Put simply:

Boilers are prone to locking up when temperatures drop below zero. Condensed flue gases freeze in the condense pipe, causing the boiler to shut down. And, that’s going to mean no hot water, no heating and an expensive emergency repair bill; bad news ☹.

The Condensesure Syphon is designed to keep your boiler operational down to -15, for a period of up to 48 hours; it’s a feature that’s going to keep your boiler running, rain or shine.

How Efficient Is This Combi Boiler?

If your boiler is 10+ years old, there’s a good chance you could be saving large chunks of cash by fitting a new one. As an example, a G-Rated boiler in a semi-detached house could cost around £200 per year more to run when compared to a brand new A-rated equivalent.

A G-Rated boiler is less than 70% efficient. The Worcester 30Si Compact? It’s 88.5% efficient when it’s running at full tilt. If it’s ticking over at around 30%, that efficiency rating can rise to a massive 99.5%.

So yeah, it’s efficient! And, that’s going to relate to pounds in your pocket when it comes to your gas bill.

Is The 30Si Compact Right For You?

If you’re looking for a compact boiler, the Worcester range is a good place to start. But, to ensure you don’t buy a boiler that’s too big (or small, for that matter), spend 90 seconds filling out this clickable form, which will give you your options on screen.

It maybe that anything from the 25Si Compact through to the 36cdi Compact is a more suitable option for your property.

What’s Next?

Thanks for reading our 30Si Compact review.

Looking for specs? The data sheet for the 30Si Compact can be found here.

Still got questions about choosing a boiler? Leave a comment or drop us a line through our contact form; we’ll get back to you as soon as possible.

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