There are many boiler brands on the market, and it can be hard to know which to choose. In this article, we going to cover why we would recommend a Vaillant Boiler.
Our dedicated team at JPS Plumbing, Gas and Electrical spends many hours working with boilers, installing, maintaining and repairing them, and have got to know them inside and out!
One brand that particularly stands out, consistently impressing our team with its quality, value for money and reliability, is Vaillant. It is, therefore, the brand we recommend the most as we always want the best for our customers.
Vaillant manufactures all common types of boilers – combi boilers, system boilers and heat-only boilers (also known as open vent boilers). We have prepared another article about boiler types.
Here is an overview of key features of their range.
Vaillant’s range of boilers
Combi boiler range
- ecoTEC exclusive with Green iQ combi
- ecoTEC plus
- ecoTEC plus combi store
- ecoTEC pro combi
- ecoFIT pure combi
System boiler range
- ecoTEC exclusive with Green iQ system
- ecoTEC plus system
- ecoFIT pure system
Heat-only boiler range
(also known as open vent boilers, conventional boilers and regular boilers)
- ecoTEC plus regular
- ecoFIT pure regular
Let’s put these boilers under the microscope…
ecoTEC exclusive with Green iQ combi
This is Vaillant’s highest specification boiler, made with stainless steel heat exchangers and brass hydroblocks. We can give a 10-year warranty on this model.
It is available in two different outputs:
- 35kW boiler, modulating down to 3.9kW
- 43kW boiler, modulating down to 4.8kW
The way these boilers modulate right the way down makes them incredibly energy efficient.
What ‘modulating down’ means is that the boiler will work itself out and use as little energy as it needs to heat the house. For example, if the house only needs 5kW of heat per hour, that’s what it will run at. It won’t run at its maximum 35kW. This is sophisticated technology compared with old boilers that used to be either on or off – in this case all 35kw, or nothing!
Modern boilers are designed to run for longer periods of time but at a lower kW rating, which is more energy efficient.
So, as this is a combi boiler, we also need to look at its hot water performance. We look for the ’35-degree rise’. For this model, the numbers are:
- 35kW boiler can run at 14.5 litres per minute of hot water
- 43kW boiler can run at 17.8 litres per minute of hot water
These numbers depend on the water flow rate that’s coming into the property. We size the boiler depending on how many litres per minute of cold water the house currently has, so that it can keep up with demand.
Another key feature to be aware of when you are appraising new boilers is the flue specifications – how far your flue needs to go will determine which boiler you can have.
For this model, both kW outputs’ flue specifications are:
- Standard horizontal flue is 5.5m (can be extended to 32m with an enlarged flue)
- Standard vertical flue is 8m (can be extended to 34m with an enlarged flue)
This versatility gives us huge scope to install these boilers practically anywhere.
ecoTEC plus combi
This is our most recommended boiler at JPS Plumbing, Gas and Electrical. It is made with stainless steel heat exchangers and brass hydroblocks and we can give a 10-year warranty on this model. As it’s quite universal, it is suitable for the majority of locations. Available in an LPG version and a natural gas version, it is A rated with an 89.4% energy efficiency rating.
This boiler is available in several different outputs:
- 25kW boiler, modulating down to 4.2kW
- 32kW boiler, modulating down to 5.7kW
- 35kW boiler, modulating down to 6.4kW
- 38kW boiler, modulating down to 7.1kW
With an ‘up to one in 6’ ratio this is slightly less than the ecoTEC exclusive with Green iQ combi, but it’s still an extremely efficient boiler.
It’s got built-in frost protection, which makes it ideal for a garage location, or anywhere else that can get very cold.
Again, being a combi boiler, the hot water performance is key:
- 25kW boiler can run at 10.5 litres per minute of hot water
- 32kW boiler can run at 13 litres per minute of hot water
- 35kW boiler can run at 14.3 litres per minute of hot water
- 38kW boiler can run at 15.9 litres per minute of hot water
We measure the property to work out what it needs, and use those measurements to spec the right boiler to meet the property’s needs. Usually, with a combi boiler, we spec it based on the hot water because the boiler is going to need a lot more power for the hot water, it will modulate itself down for the heating.
This model’s flue specifications:
- 25kW Standard horizontal flue is 12m (can be extended to 39m with an enlarged flue)
- 25kW Standard vertical flue is 16m (can be extended to 41m with an enlarged flue)
- 32kW, 35kW and 38kW Standard horizontal flue is 5.5m (can be extended to 32m with an enlarged flue)
- 32kW, 35kW and 38kW Standard vertical flue is 8m (can be extended to 34m with an enlarged flue)
Again, this versatility gives us huge scope to install these boilers practically anywhere.
ecoTEC pro combi
This model is very similar to the ecoTEC plus, including having stainless steel heat exchangers and brass hydroblocks. However, it has slightly less modulation, slightly less hot water performance, and only a 7-year warranty instead of a 10-year warranty.
This boiler has three output options:
- 24kW boiler, modulating down to 5.9kW
- 28kW boiler, modulating down to 6.9kW
- 30kW boiler, modulating down to 9kW
The modulation ratio is one in four, so less than the ecoTEC plus.
For a 35-degree rise, the hot water performance is:
- 24kW boiler can run at 9.6 litres per minute of hot water
- 28kW boiler can run at 11.1 litres per minute of hot water
- 30kW boiler can run at 12.3 litres per minute of hot water
This model’s flue specifications (it’s the same for all the kW output models) are:
Standard horizontal flue is 12m (can be extended to 39m with an enlarged flue)
Standard vertical flue is 16m (can be extended to 41m with an enlarged flue)
We don’t generally ever recommend fitting this model of boiler, as the ecoTEC plus is so similar but has a longer warranty, more modulation and better hot water performance.
ecoFIT pure combi
This combi boiler is lower priced than the Ecotec plus, which explains the lower quality aluminium heat exchanger and plastic hydroblocks. Although it comes with a 10-year warranty, we tend to not recommend this boiler but would instead recommend the Baxi boiler as it is similarly spec’d and priced but has the higher quality stainless steel heat exchangers and brass hydroblocks.
One scenario where we would recommend the ecoFIT pure combi over the Baxi boiler is if we need a rear flue option due to space restrictions, rather than having space for the flue to come out of the top.
This boiler has three output options:
- 25kW boiler, modulating down to 5.3kW
- 30kW boiler, modulating down to 6.3kW
- 35kW boiler, modulating down to 7.5kW
The modulation ratio is one in five, which is slightly less than the ecoTEC plus.
For a 35-degree rise, the hot water performance is:
- 25kW boiler can run at 10.4 litres per minute of hot water
- 30kW boiler can run at 12.2 litres per minute of hot water
- 35kW boiler can run at 14.1 litres per minute of hot water
This model’s flue specifications (the same for all kW output models) are:
Standard horizontal flue is 10m (can be extended to 25m with an enlarged flue)
Standard vertical flue is 10m (can be extended to 25m with an enlarged flue)
Controls for combi boilers
For Vaillant combi boilers, we would usually fit the wireless VRT 350f programmable thermostat. It comes with a 10-year warranty if fitted as part of a boiler installation.
The 350f has intelligent load compensating technology which helps the boiler modulate to only use the energy that the property needs.
This thermostat is also Boiler Plus compliant; government legislation which we must now adhere to.
ecoTEC exclusive with Green iQ system
Essentially, this Vaillant boiler is the system boiler version of the Green iQ combi boiler. It has a stainless steel heat exchanger and brass hydroblocks, and we can give you a 10-year warranty.
It only comes in a 27kW option, which modulates down to 4.2kW.
As there is no hot water output with a system boiler there are no hot water performance figures.
This model’s flue specifications are:
Standard horizontal flue is 5.5m (can be extended to 32m with an enlarged flue)
Standard vertical flue is 8m (can be extended to 34m with an enlarged flue)
ecoTEC plus system
This is our mostly widely recommended system boiler. It has a stainless steel heat exchanger and brass hydroblocks, and we can give you a 10-year warranty.
This boiler model is available in several output options:
- 12kW boiler, modulating down to 3.3kW
- 15kW boiler, modulating down to 3.3kW
- 18kW boiler, modulating down to 4.1kW
- 24kW boiler, modulating down to 5.7kW
- 30kW boiler, modulating down to 6.4kW
- 37kW boiler, modulating down to 7.1kW
We will work out which output option you will need by sizing it to the house, based on what your house needs to heat up. We estimate that as 1.5 kW per radiator plus your hot water cylinder – that will vary depending on whether you have a vented hot water cylinder or an unvented hot water cylinder.
This model’s flue specifications:
- 12kW and 15kW Standard horizontal flue is 22m (can be extended to 25m with an enlarged flue)
- 12kW and 15kW Standard vertical flue is 26m (can be extended to 27m with an enlarged flue)
- 18kW Standard horizontal flue is 12m (can be extended to 39m with an enlarged flue)
- 18kW Standard vertical flue is 16m (can be extended to 41m with an enlarged flue)
- 24kW, 30kW and 37kW Standard horizontal flue is 5.5m (can be extended to 32m with an enlarged flue)
- 24kW, 30kW and 37kW Standard vertical flue is 8m (can be extended to 34m with an enlarged flue)
ecoFIT pure system
It comes with a 10-year warranty but we wouldn’t recommend this boiler as it has an aluminium heat exchanger and plastic hydroblocks. Instead, we would recommend the ecoTEC plus or, if we were looking for a cheaper option, we would recommend Baxi because as it has a 10-year warranty and comes with a stainless steel heat exchanger and brass hydroblocks.
It comes in a range of output options:
- 12kW boiler, modulating down to 4.7kW
- 15kW boiler, modulating down to 4.7kW
- 18kW boiler, modulating down to 5.5kW
- 25kW boiler, modulating down to 6.4kW
- 30kW boiler, modulating down to 7.5kW
This model’s flue specifications (the same for all kW output models) are:
- Standard horizontal flue is 10m (can be extended to 25m with an enlarged flue)
- Standard vertical flue is 10m (can be extended to 25m with an enlarged flue)
Controls for system boilers
We don’t recommend a Vaillant control system for Vaillant system boilers as the wiring centres have another PCB in them which is another thing that could go wrong and makes your heating system over complicated.
Instead, we generally fit a Drayton Digistat or a smart thermostat like a Nest or a Hive.
ecoTEC plus regular heat-only
Vaillant do not manufacture a heat-only/open vent boiler variant in the ecoTEC exclusive range. Their highest specification model for this type of boiler is the ecoTEC plus. Even though it has a 10-year warranty, this is the only boiler where we feel that recommending the more premium ecoTEC plus boiler over the ecoFIT pure model is not justified as the ecoFIT pure boiler is cheaper and essentially the same product. In other types of Vaillant boiler the ecoTEC plus range has stainless steel heat exchangers and brass hydroblocks but the heat-only ecoTEC plus boiler has aluminium heat exchangers and plastic hydroblocks.
It comes in a range of output options:
- 12kW boiler, modulating down to 4.7kW
- 15kW boiler, modulating down to 4.7kW
- 18kW boiler, modulating down to 5.2kW
- 24kW boiler, modulating down to 6.3kW
- 30kW boiler, modulating down to 7.5kW
- 35kW boiler, modulating down to 7.5kW
This model’s flue specifications (the same for all kW output models) are:
- Standard horizontal flue is 10m (can be extended to 25m with an enlarged flue)
- Standard vertical flue is 10m (can be extended to 25m with an enlarged flue)
ecoFIT pure regular heat-only
We recommend this model over the ecoTEC plus boiler as its generally £100 cheaper than the plus model, even though it’s essentially the same because it still has an aluminium heat exchanger and plastic hydroblocks.
It comes in a range of output options:
- 12kW boiler, modulating down to 4.7kW
- 15kW boiler, modulating down to 4.7kW
- 18kW boiler, modulating down to 5.2kW
- 25kW boiler, modulating down to 6.4kW
- 30kW boiler, modulating down to 7.4kW
- 35kW boiler, modulating down to 7.5kW
This model’s flue specifications (the same for all kW output models) are:
- Standard horizontal flue is 10m (can be extended to 25m with an enlarged flue)
- Standard vertical flue is 10m (can be extended to 25m with an enlarged flue)
This model has a rear flue option.
As a general rule of thumb across the whole range of heat-only boilers, we spec the Vaillant ecoFIT pure because the Baxi (Main) alternative is a completely different boiler and for heat-only boilers we feel that Vaillant is the superior choice. However, when it comes to combi and system boilers, a Baxi boilers is often a high quality, lower cost alternative option to a Vaillant.
Controls for heat-only/open vent boilers
We don’t recommend a Vaillant control system for Vaillant system boilers as the wiring centres have another PCB in them which is another thing that could go wrong and makes your heating system over complicated.
How can I contact you to find out more?
Whatever your needs, or whatever queries you may have, please call or email our knowledgeable, experienced and friendly team at JPS Plumbing, Gas and Electrical who will be very happy to help you.
Southampton office: 02381 733139
Winchester office: 01962 448013
Email: admin@jpsplumbing-winchester.co.uk
All technical detail in this article was correct on the date of publication.