50kw Combi Boiler

50kw combi boiler

50kw combi boiler; 50 kw gas combi boiler;

Our Flexiheat 50kW combi boiler is a well-designed condensing combination boiler with 97% efficiency making this an “A” rated boiler for heating and hot water. Due to this efficiency, it can reduce fuel bills and reduce your carbon footprint as it can generate enough heat to meet the demand of your home using less fuel than an older inefficient boiler. The boilers installation is easy, and we can supply the boiler in either natural gas or LPG (Propane) gas

Combi boilers are one-of-a-kind, compact, and cost-effective solution that are ideal for houses with limited space. They combine a water heater and a central heating boiler into a single device, eliminating the need for additional water cylinders or tanks in your home.

With boilers account for approximately 60% of a household’s yearly energy costs, they have an enormous impact on fuel bills. With more seasoned older gas boilers, a significant sum of heat that may be utilized to produce warming and hot water is wasted, making them progressively costly to run.

Our 50KW combi boiler is more than 97% efficient, so 97p of each £1 you spend on gas for your combi boiler is utilized.When using an Opentherm internet-connected Smart controller, you can control our ERP “A” rated device, on the go from your mobile, or tablet – now becoming a must for people with busy lives.

ErP A-rated for both heating and hot water, this efficient, reliable combi boiler provides effortless comfort at a reduced running cost. All while you sit comfortably in complete peace of mind, knowing that you have a highly efficient 50kw combi boiler, that is also one of the quietest in its class at 52 decibels installed (for comparison a refrigerator is around 50 Decibels).

Key features of our 50kW combi boiler are –


1.Increased power- compared to the competition – we actual make a 50kW combi boiler – that will do 53.85 kW of heating power based on an 50C/30C flow and return system, or 49.19kW at 80C/60C.


2.Fantastic new design – this 50kW combi boiler benefits from aesthetically pleasing looks


3.increased burner modulation ratio of 1:10, which prevents on/off cycling for a lengthy product life.


3.It’s inbuilt intuitive controller, which benefits from an intuitive menu structure for, commissioning, and fault finding if so required, which means no need to search through manuals for fault codes. Resulting in rapid diagnosis of any issues. Not that you’ll use the fault finding much with our quality range of efficient 50kw gas fired combination boilers


4.Servicing – With plenty of room within the appliance casing – this range of 50kW combi boilers is installers dream to work on.


5.Installation of the boiler – which must be done by gas safe qualified installers or company – can be in any location, as we do various flue options, such as a room sealed range (see details below) also being one of the quietest boilers, you’ll have complete peace where ever you locate the boiler.


6.Can be operated on a system pressure of 0.3 to 2.1 Bar for the heating side and 0.5 to 6 Bar system pressure for the Domestic Hot Water side of the appliance


7.This range of combi boiler is suitable for natural gas or LPG (must be specified at date of customers order) – sit comfortably knowing if you change your gas type the boiler is easily converted over.


8.DHW flow rate at a 35 Degrees C temperature rise is 20.30 litres/min or at a 40 Degrees C rise then its 17.5 litres/min. 


Heating system side of the boiler

Central heating output – Based on flow and return temperatures of 80/60 and the fact that current new build homes have radiators that on an average of 1.5kw output the 50kw combi boiler can produce 53.85kw of output power which is enough to heat up to 35 radiators on the system. (Please note: If retrofitting, the number of radiators cannot exceed the out power of the boiler at 53.85kw in total)

Some of our competitors claim a 50 kW combi – but in reality, the heating side of the boiler is only 35 kW of output

There is not may companies producing a 50kw combination boiler, some people may regard a boiler produced by the Worcester Bosch company – namely the worcester greenstar 8000 50kw combi boiler range as a direct competitor to our boiler, but in reality, this boiler, will only produce –

Central heating output (kW) – 33.8 kW at 80/60C or at 50/30C condensing mode – 35.7 kW

While our unit will produce 49.19 kW of heating power at 80/60C or at 50/30C condensing mode – 53.85 kW

Thus, can you really call the worcester greenstar 8000 a 50 kW combi ?? you decide, but it seems a bit short to us?

On the Domestic Hot Water performance –

The worcester greenstar 8000 is 48.9 kW rated on the dhw side, the dhw output is –

Flow at the DHW tap (35°C temperature rise) – 20.3 l/min

Flow at the DHW tap (40°C temperature rise) – 18 l/min

With a plus or minus of 15%  quoted.

Whilst our boiler will produce the following outputs

Flow rate at the DHW tap (35°C temperature rise) – 20  l/min

Flow rate at the DHW tap (40°C temperature rise) – 17.5 l/min

There’s no plus or minus 15% for our data – we will produce those figures quoted above

Domestic hot Water performance

Due to its excellent domestic hot water flow rate, with a temperature rise of 30 degrees C @ 23.40 ltrs/min of hot water flow or with a temperature rise of 35 degrees C @ 20 ltrs/min, the 50kW combi boiler is ideal for a two-bathroom house.


Heat Exchanger

These devices are equipped with a stainless-steel exchanger with a large Ø 28mm monotube coils, which not only benefits from very low pressure drops, but guarantees lower risk of clogging, with greater thermal efficiency, and greater ease of cleaning. We guaranteed the heat exchanger for 10 years, when a good quality magnetic dirt and air separator is fitted to the system, and the devices is serviced annually.

Technical Data




large combi boiler UK; inc vat; bosch easycontrol; Best 50kW combimation boiler

Best 50kW combination boiler; gas fired combi for a large house; inc vat;date

inc vat; increased power; intuitive menu structure; customers; fantastic new design;company

Download the 50kW Combi Boiler Manual Fleixheat UK

Boiler Flue Options

We do various flue options, the most common is a co-axial, which takes the combustion air from outside, and the combustion gases from the device to the outside – making these combi units room sealed when used.

The most common flue kit is our horizontal co-axial kit – both of these can be used up to 10 metres in length

Horizontal flue kit from flexiheat UK;worcester greenstar 8000;ex vat;worcester bosch;ex vat;worcester bosch;ex vat;inc vat;quietest boilers;inc vat;ex vat

Horizontal kit from Flexiheat UK


Or the vertical option

Vertical flue kit from Flexiheat UK;ex vat;worcester bosch;worcester greenstar 8000;ex vat;worcester bosch;ex vat;worcester bosch

Vertical kit from Flexiheat UK


Both of these can be used up to 10 metres in length, losing 0.8 metres off the length for every 90° elbow used, and 0.5 metres for every 45° elbow used from the overall distance.

Or by using a split system, we can achieve routes of up to 60 metres

boiler Split flue pipe system;

Split pipe system from Flexiheat UK

Boiler controls

With an easy-to-use display with an intuitive menu structure and greater connectivity with any Opentherm compatible controller, our 50kw combi or combination boiler is made to suit your lifestyle, as well as your home.

One of the new features of OpenTherm – (which is a standard communication system that connects natural gas, lpg gas, oil or even electric boilers with room thermostats). This means that your combi boiler can be used with any OpenTherm compatible thermostats or controllers – the best-known brand on the UK market to date is between Nest or Hive, but we also provide a solution from stock, which has extended range, and key features such as the ability to control your boiler from a mobile phone, pad or your computer.

This means if your away on from home, you can have controllers that will activate your boiler based on your postcode location in relation to your property – so it’s nice and warm when you get in or should you be travelling, you can adjust the boiler start time in relation to when your due home on your phone or other device, should you be delayed for any reason you simply adjust the time on your device.

Class 5 modulating controls, can provide an increase of 3% system efficiency, as they have a direct impact on the efficiency of the modulating combi boiler, by modulating the flow temperature in line with the internal temperature of the property.

Easy Remote

Advanced class 5 remote control, which performs the dual function of a thermostat and remote control of the boiler. This controller must be wired from its location to the appliance

Easy remote controller from Flexiheat UK; Class 5 modulating boiler controller range;bosch easycontrol;stock;website;inc vat;delivery;stock;England;delivery;intelligent filling system;worcester greenstar 8000:stock;inc vat

Easy remote controller – Wired – from Flexiheat UK

  • Daily / weekly heating and DHW programming;
  • Heating system and DHW temperature setting;
  • Reset by remote control in the presence of resettable fault codes;
  • Thermoregulation management;
  • Appliance parameter programming (technician level)


Cloud Warm WIFI (Wireless) Controller

A free-standing class 5 advanced remote control thanks to the free downloadable app which performs the dual function of chrono thermostat and remote control of the device from a mobile phone or tablet.

Cloud Warm Wired controller from Flexiheat UK; stock;delivery;stock;website;inc vat;stock;delivery;stock;worcester greenstar 8000;ex vat

Cloud Warm Wired controller from Flexiheat UK


  • Daily / weekly heating and DHW programming;
  • Cloudwarm application available for free on the Apple Store and Google Play; No annual charges to pay
  • Heating and DHW temperature setting;
  • Push notifications to a mobile device in the presence of any abnormality or fault;
  • Reset from a mobile device in the presence of resettable fault codes;
  • Thermoregulation management;

Cloud Warm WIFI (Wired)

As above functions, but this unit must be wired back to the 50kw combi boiler
Stock;delivery;ex vat;worcester bosch; inc vat;worcester bosch;ex vat;inc vat; ex vat;inc vat;ex vat; ex vat;inc vat;ex vat;inc vat;ex vat;inc vat

Cloud Warm Wireless Opentherm controller from Flexiheat UK



Brand and Quality manufacturing

Our 50kw combi boiler is manufactured in accordance with ISO 9001 and ISO 1400 certified management systems and testing techniques. Should you require more information, prices or delivery times, then please contact our sales teams for the best 50kw gas combi boiler on the UK and Irish market. You can call our office on 01202 822221 or send an email via our contact form.