120 Litre Direct Unvented Cylinder

120 Litre direct unvented cylinder

120 Litre direct unvented cylinder in highly corrosion resistant duplex stainless steel with 2 x 3kW immersion heaters for mains pressure hot water

120 Litre direct unvented cylinders in corrosion resistant duplex stainless steel from Flexiheat UK

 

Our 120 litre direct unvented cylinder is engineered in corrosion-resistant duplex stainless steel and is a competitively priced cylinder. We designed it to achieve high flow rates and a long product life using proven technology and a quality manufacturing process for this unvented hot water cylinder for mains pressure hot water.

We’re so sure of the quality of our 120 litre unvented direct cylinder that they come with a 25-year warranty for use in residential locations like homes, apartments, and so on. The warranty covers the stainless steel hot water cylinder for 25 years, while the other parts, like the immersion heaters, control thermostats, and so on, are covered for one year from the date of purchase, subject to conditions.

What is a 120L direct unvented cylinder suitable for?

A rough guide is that 120 litre direct unvented hot water cylinders suit flats or smaller homes with one or two bedrooms and a bathroom with one bath and/or shower.

However, people’s hot water usage patterns can vary from household to household. We prefer to give you the hot water usage data, and you, our customer, decide if it suits your hot water needs.

In the United Kingdom, we are required to keep DHW at 60°C since it eliminates the possibility of Legionella disease and is the minimum recommended water temperature.

If the stored water temperature is 60°C, the amount of required water is in red, to be blended down to 43°C (the maximum bathing temperature before scalding can occur).

Please use 10°C for England and Wales as the lowest cold-water wintertime temperature and use 5°C for Scotland and Northern Ireland.

If the incoming cold-water temperature                                            is 10°C                                   is 5°C

A bath uses around 135 litres of water at 43°C                                 89 litres                                 94 litres

A standard 8-litre shower head x 5 minutes                                     30 litres                                 31 litres

And yes, 5 minutes is the average showering time—say all the time and motion studies report.

A kitchen sink holds up to 20 litres of water                                    16 litres                                   16.5 litres

To ensure the removal of grease from dishes and cooking utensils, the standard temperature for washing up water is 50°C.

Toilet sink taps—standard type—are around 4 litres per minute; “spray” type taps are 2 litres per minute and tend to be on for a brief period.

Please see the recovery time data below for our 120L direct cylinder to establish if this is the right 120L electric water heater for your circumstances and demands.

This 120 Litre volume direct unvented cylinder is the second most popular seller in this range, however, should you wish a larger volume cylinder, which is  our most popular direct unvented cylinder that we sell, then please see the following webpage – 150 Litre direct unvented cylinder

Hot water heat-up time and recovery rates for our direct unvented cylinder, 120 litres in capacity

As standard, our 120 litre direct-pressurised hot water cylinders in high grade stainless steel are fitted with 2 x 3 kW immersion heaters with proven technology and quality.

Our 120 Litre unvented indirect cylinder has the following hot water heat-up time and recovery rates with standard 2 x 3 kW immersions fitted:

Hot water heating and recovery times for our 120 Litres direct unvented cylinders -130 Litre actual from Flexiheat UK

Hot water heating and recovery times

Upgraded immersion heater options 

We have the option of upgrading the immersion heaters to larger outputs for rapid heat recovery.

We can supply this 120 Ltr capacity direct unvented cylinder with 2 x 6kW immersion heaters, which can be wired in either 1 phase/240 volts (32 amps per immersion is required) or 3 phases (10.66 amps per phase is required); this will halve the recovery times stated above in the chart. We also must upgrade the standard temperature and pressure relief valve to a larger output model.

Or alternatively, you can have 1 x 6kW and 1 x 3kW immersion heater fitted, for a total kW input of 9kW; the standard 10kW T & P valve will remain if this configuration is used.

All of our unvented cylinders have a pressure test, and all are tested to 10 bar pressure and have a max working pressure of 5.5 bar.

Unvented hot water expansion system

The patented internal hot water expansion system, which uses a venturi valve to maintain an air pocket within the stainless steel cylinder, eliminates the need for an external expansion vessel. This unvented system has a long product life because it has no moving parts, which reduces running and lifetime costs.

Internal air gap system for our direct unvented hot water cylinders- no external expansion vessel is required as this is a self-sustaining air gap in our unvented hot water cylinder range that requires little to no maintenance ensuring mains pressure hot water flow throughout the property whatever the heat source feeding the unvented hot water cylinder.

Our internal air gap and venturi valve system used on our direct unvented hot water cylinders- no external expansion vessel is required and little to no maintenance is required for the unvented hot water system.

 

As a result, our direct unvented cylinders need less space, pipework and plumbing fittings, making the installation process simpler and lowering both costs and time required for installation.

Unvented Direct Cylinder 120 Litres: Features and Benefits

  • Enhanced Venturi valve technology, which automatically replenishes the internal air gap within the unvented cylinder.
  • Dual immersion cylinder: 2 x 3kW immersion heaters as standard.
  • 3 bars of water pressure at the outlet (subject to incoming pressure).
  • Mains pressure hot water directly delivered—enabling high flow rates.
  • No expansion vessel or moving parts, ensuring low maintenance.
  • ErP “B” heat loss rating for reduce energy consumption
  • Benefits from an evolved design and quality manufacturing for improved performance at low flow rates.

120 litre unvented direct cylinder dimension

Our 120 litre stainless steel direct unvented cylinder has the following dimensions:

Dimensions drawing of our direct unvented cylinders in duplex stainless steel - 80 litre to 500 Litre - Flexiheat UK

Unvented direct hot water cylinders – Dimensions drawing for 80 Litre to 500 Litre models

 

The highly corrosion-resistant duplex stainless steel 120 Ltr capacity direct unvented cylinder has the following engineered dimensions in mm:

 

Direct unvented 120 Litre cylinder in stainless steel dimensions, which is a direct pressurised hot water cylinder and a dual immersion cylinder from Flexiheat UK

130L Direct pressurised hot water cylinder details highlighted in red – yes, we give you 10 more litres of capacity for free, as they can hold / have 130 Litres of capacity.

 

Our duplex stainless steel cylinders are available in both direct and indirect configurations as you can see in the following manual 

Download the installation & technical manual for our direct and indirect hot water cylinders

Unvented direct cylinder 120 ltr approvals

Our 120 ltr direct unvented cylinder we sell has been approved by the CE, BBA, and WRAS independent approvals (Water Regulations Approval Scheme—a certification body for domestic hot water heating products that assists businesses and customers choose safe products that comply with hot water regulations) and benefits from ISO, KIWA, and WRC approvals as well, proving the quality manufacturing process of our stainless steel cylinders.

Components supplied with our stainless steel unvented cylinder: 120L direct unvented cylinder

2 x 3kW immersion heaters manufactured in incoloy (a super austenitic stainless steel—with high resistance to oxidation), with a control thermostat and high-temperature thermal/energy cut-out thermostat.

Front access to the controls on our electric pressurised hot water cylinder.

A temperature and pressure relief valve to comply with the hot water unvented cylinder regulations.

A complete pressure-reducing valve combination valve/6-bar expansion relief valve (the maximum inlet pressure to the mains pressure hot water cylinder) for the cold water mains inlet 

A Tundish: A Tundish has a clear window that allows you to see if water is flowing from the pressure relief valve (PRV). This helps you identify potential issues with the unvented hot water system.

Heat loss ErP rating for this direct unvented cylinder

This direct unvented cylinder has an ErP level of “B” for the thermal insulation to reduce heat loss and ensure running costs are kept to a minimum, which is an excellent rating for an unvented direct cylinder.

The injected polyurethane foam thermal insulation, with an ODP=0 and a GWP=1 rating, is free of CFC/HCFC and provides 60mm of fire-retardant protection. Similar competitor products only have 40 mm insulation to reduce heat loss, and thus the ErP insulation ratings are lower than our direct unvented cylinder.

Delivery of the unvented cylinder

We deliver these direct unvented cylinders on a small pallet delivery service that comes on a lorry directly, with your responsibility to offload. We can upgrade the delivery service to have a tail lift at request to get the stainless steel 120L direct unvented cylinder to floor level.

Contact Flexiheat UK

Please contact us at 01202 822221 to answer any questions or use the company site contact email form to get more information or details, the current stock situation, delivery options, or a cost on the best 120 litre direct unvented cylinder/120Ltr unvented direct cylinder models on the UK market. These are manufactured from high-grade duplex stainless steel (a high-grade stainless steel), with a 25-year warranty, with WRAS independent approvals, have a built-in expansion system, and are a competitively priced cylinder.

150 Litre Direct Unvented Cylinder

150 Litre direct unvented cylinder

150 Litre direct unvented cylinder in highly corrosion resistant duplex stainless steel with 2 x 3kW immersion heaters for mains pressure hot water fromFlexiheat UK

150 Litre direct unvented cylinders in corrosion resistant duplex stainless steel for mains pressure hot water from Flexiheat UK

Our 150 Litre direct unvented cylinder is a competitively priced cylinder manufactured for mains pressure hot water and engineered in corrosion-resistant duplex stainless steel for high flow rates and longevity of performance via quality manufacturing processes.

So confident are we in the quality of our 150 litre unvented direct cylinder that for use in domestic locations, such as homes, flats, etc., they have a 25 year guarantee for these direct unvented cylinder models (the stainless steel hot water cylinder has a 25 year warranty; the ancillary components, i.e., the immersion heaters, control thermostat, etc., have a one year warranty.

An unvented water heating system delivers mains pressure hot water, enabling high flow rates for showers and baths without the need for a hot water booster or boost pump.

Patented unvented hot water expansion system

With a patented internal hot water expansion system, via a venturi valve to maintain an air pocket within the cylinder, it ensures an external expansion vessel is not required. This unvented system has a long product life because it has no moving parts, which reduces running and lifetime expenses.

Internal air gap system for our direct unvented hot water cylinders- no external expansion vessel is required as this is a self-sustaining air gap in our unvented hot water cylinder range that requires little to no maintenance ensuring mains pressure hot water flow throughout the property whatever the heat source feeding the unvented hot water cylinder.

Our internal air gap and venturi valve system used on our direct unvented hot water cylinders- no external expansion vessel is required and little to no maintenance is required for the unvented hot water system.

Due to this, our direct unvented cylinders require less space, pipework, and pipe fittings, which simplifies the installation and reduces install costs and time.

Features and benefits

  • Enhanced Venturi valve technology which automatically replenishes the internal air gap within the unvented cylinder.
  • 3 bars of water pressure at the outlet (subject to incoming pressure)
  • Mains pressure hot water – enabling high flow rates
  • No expansion vessel or moving parts, ensuring low maintenance
  • Energy cut out thermostat for saftey
  • Evolved design for improved performance at low flow rates

Download the installation notes for the internal air gap valve and system for unvented hot water cylinders

A 150L direct unvented cylinder is suitable for?

A rough guide is that 150 litre direct unvented hot water cylinders are suitable for flats or smaller homes with one or two bedrooms with one bath and/or shower.

However, people’s hot water usage patterns can vary from household to household. We prefer to give you the hot water usage data, and you can make the decision, as they say.

In the United Kingdom, we are required to keep DHW at 60°C since it eliminates the possibility of Legionella disease and is the minimum recommended water temperature.

If the stored water temperature is 60°C, the amount of required water is in red, to be blended down to 43°C (the maximum bathing temperature before scalding can occur).

Please use 10°C for England and Wales as the lowest cold-water wintertime temperature and use 5°C for Scotland and Northern Ireland.

If the incoming cold-water temp                                              is 10°C                                   is 5°C

A bath uses around 135 Litres of water at 43°C                    89 litres                                 94 litres

A standard 8 Litre shower head x 5 minutes                         30 litres                                 31 litres

And yes 5 minutes is the average showering time – say all the time and motion studies report.

A kitchen sink holds up to 20 litres of water                          16 litres                                   16.5 litres

N.B Washing up water temperature is normally 50C to ensure that grease is removed from dishes and cooking utensils.

Toilet sink taps—standard type—are around 4 litres per minute; “spray” type taps are 2 litres per minute and tend to be on for a brief period.

Please see the recovery time data below for our 150l direct cylinder to establish if this is the right 150l electric water heater for your circumstances and demands.

This 150 Litre volume direct unvented cylinder is the most popular seller in our range, however, should you wish a smaller volume cylinder, then please see the following webpage – 120 Litre direct unvented cylinder, this is our second most popular direct unvented cylinder that we sell.

150 litre unvented direct cylinder dimension

Our 150 litre stainless steel direct unvented cylinder has the following dimensions:

Dimensions drawing of our direct unvented cylinders in duplex stainless steel - 80 litre to 500 Litre - Flexiheat UK

Unvented direct hot water cylinders – Dimensions drawing for 80 Litre to 500 Litre models

 

 

For the 150 Litre capacity direct unvented cylinder manufactured in highly corrosion resistant duplex stainless steel, the dimensions are:

Direct unvented 150 Litre cylinder dimensions for our internal expansion unvented hot water system Flexiheat UK

150L direct highlighted in red

 

Download the installation & technical manual for our direct and indirect hot water cylinders

Being manufactured with high grade stainless steel and using quality manufacturing processes for the cylinder ensures long product life.

Hot water heat-up time and recovery rates for our direct unvented cylinder 150 litre volume

As standard our 150 litre direct pressurised hot water cylinders in high grade stainless steel are fitted with 2 x 3kW immersion heaters 

Our 150 Litre unvented indirect cylinder has the following hot water heat-up time and recovery rates with standard 2 x 3kW immersions:

 

Hot water heating and recovery times for our 150 Litre direct unvented cylinders from Flexiheat UK

Hot water heating and recovery times

Upgraded immersion heater options 

We have the option of upgrading the immersion heaters to larger outputs for rapid heat recovery –

We can supply this with 2 x 6kW immersion heaters which are be wired in either 1 Phase/ 240 volt (32 amps per immersion is required) or 3 Phase (10.66 amps per phase is required), this will half the recovery times stated above in the chart. We also must upgrade the standard Temperature and pressure relief valve to a larger output model

Or alternatively you can have 1 x 6kW and 1 x 3kW immersion heater fitted, for a total kW input of 9kW, the standard 10kW T & P valve will remain if this configuration is used.

All of our unvented cylinders have a pressure test, and all are tested to 10 bar pressure. The maximum working pressure is 5.5 bar.

Our unvented cylinders are available in direct and indirect configurations at a competitive price.

Components supplied with our stainless steel unvented cylinder: 150L direct unvented cylinder

2 x 3kW immersion heaters manufactured in incoloy (a super austenitic stainless steel—with high resistance to oxidation), with a control thermostat and high temperature thermal/energy cut-out thermostat.

Front access to the controls on our electric pressurised hot water cylinder

A temperature and pressure relief valve to comply with the unvented cylinder regulations.

A complete pressure reducing valve combination valve/6-bar expansion relief valve for the cold water mains inlet

A Tundish – A tundish has a clear window that allows you to see if water is flowing from the pressure relief valve (PRV). This helps you identify potential issues with the unvented hot water system.

Heat loss ErP rating for this direct unvented cylinder

This direct unvented cylinder, 150 litres in capacity, has an ErP level of “B” for the thermal insulation / to reduce heat loss and ensure running costs are kept minimum,which is a very good heat loss rating for an unvented direct cylinder.

The thermal insulation, which is a injected polyurethane foam is CFC/HCFC free, with an ODP=0 and a GWP=1 rating, being 60mm fire-retardant insulation. Similar products only have 40mm insulation to reduce heat loss , and thus the ErP insualtion ratings are lower than our direct unvented cylinder.

Unvented direct cylinder 150 litre approvals

Our 150 ltr direct unvented cylinder has the following approvals: CE, BBA, and WRAS independent approvals (Water Regulations Approval Scheme—a certification body for domestic hot water heating products that assists businesses and customers choose safe products that comply with regulations) and benefits from ISO, KIWA, and WRC approvals as well, proving the quality manufacturing process of our stainless steel cylinders.

Unvented cylinder delivery

We deliver these direct unvented cylinders on a small pallet delivery service that comes on a lorry, with your responsibility to offload. We can upgrade the delivery service to have a tail lift at request to get the stainless steel 150L direct unvented cylinder to floor level.

Contact Flexiheat UK

Please call us at 01202 822221 to answer any questions or use the contact form above to get more information, the current stock situation, delivery options, or a cost on the best 150 litre direct unvented cylinder/150Ltr unvented direct cylinder models on the UK market. These are made from high-grade duplex stainless steel (A high grade stainless steel) ,with a 25 year warranty, with WRAS independent approvals, have a built-in expansion system, and are a competitively priced cylinder.

Highest Flow Rate Combi Boiler

Highest Flow Rate Combi Boiler ? High domestic hot water flow rate combination boiler

Our high flow rate combi boiler from Flexiheat UK. This 50kW combination boiler is the highest flow rate combi boiler on the UK market, which is a combi boiler for two showers

Combi boiler with highest flow rate – Flexiheat UK

Our 50kW combination boiler is the highest flow rate combi boiler / combi boiler with the highest flow rate (23.4 litres per minute with a temperature rise of 30°C) on the UK market. No other combination boiler comes close to this high flow rate combi boiler, which is available in natural gas or LPG (propane) gas boiler.

With a combination boiler, you’re only heating the cold water up to the normal domestic hot water temperature of 38°C to 40°C on demand, so you save money on your hot water bills, as you’re not heating a hot water cylinder storage up that may not be used in its entirety.

Most combi boilers on the UK market have average hot water capabilities and aren’t suitable for more than one bathroom homes.

Our combination boiler is ideally suited to properties with high flow rate requirements, especially large properties with two showers or more that can be used at the same time.

With exceptional performance, being ErP rated “A” for both heating and hot water, making our boiler the right choice as a new boiler or retrofit replacement replacements especially in larger homes.

Our 50kW combination boiler type is the right boiler for homes or properties with high demands for heating and hot water.

What is a Combi Boiler?

A combi boiler is a type of heating system that provides both a central heating system and a domestic hot water supply in one unit. A combination boiler produces instantaneous hot water on demand.

Combi boilers are ideal for homes or properties with limited space, as they eliminate the need for a separate hot water cylinder and a system boiler, reducing installation costs.

They are also known for their energy efficiency (energy-saving by the fact that your heating domestic hot water on demand when required) and cost-effectiveness.

Our combination boilers are not suitable for an open-vented system like conventional boilers. The system needs to be converted to a sealed system by heating engineers.

There are storage combi boilers on the market, but you don’t need storage combi boilers when you have the hot water requirements fulfilled with a true combination boiler. 

Understanding Combi Boiler Flow Rate

What does the term “flow rate” mean?

The amount of hot water that a combi boiler can supply to your hot water outlets (such as taps or showers) in a minute is indicated by its flow rate, i.e.,

  • Combi boiler flow rate refers to the amount of hot water a boiler can provide in a set timeframe, normally quoted as litres per minute, at a standard temperature rise of 30°C for the domestic hot water from the cold mains water supply.

However, everything is dependent on how quickly your home’s main water supply flows. It will never reach the desired level if your mains flow rate is less than the combi boiler’s flow rate.

  • Mains water supply pressure will affect the flow rate of a combi boiler.

A combi boiler could achieve a flow rate of 20 litres per minute, for instance. In your home, that equates to 20 litres of hot water per minute. However, the combination boiler will not be able to achieve 20 litres per minute if the mains water supply flow rate is only 10 litres per minute to the property.

A higher flow rate means more hot water can be supplied, making a combi boiler with the highest flow rate suitable for homes, especially larger homes with multiple bathrooms (two or more bathrooms) or high hot water demand.

Factors Affecting Flow Rate

Water flow rate is the volume of water that runs through a pipe, while water pressure is the force that pushes the water through the pipe.

A number of factors influence the flow rate, including:

  1. The mains pressure and mains supply flow rate to the property
  2. The length of the pipe from the cold mains to the home
  3. The diameter of the pipe from the main supply.
  4. The surface characteristics of the pipe (frictional resistance) and the number and angle of any bends in it from the mains to your property.

There is a relationship between water flow rate and water pressure. Flow rate rises with increasing water pressure, and flow rate typically decreases with decreasing water pressure. However, it is possible that a high water pressure might have a low flow rate, and vice versa.

  • Water pressure affects flow rates, and a more powerful combi boiler can heat water faster, but only if the mains water pressure is sufficient.
  • A local installer / heating engineer can help determine the water pressure and flow rate in a home.
  • The number of bathrooms and taps in a home also affects the required domestic hot water flow rate.

How to Check Your Home’s Water Flow Rate

You can perform a simple test to find out the current flow rate in your home by filling an empty measuring container with water and measuring the time it takes to fill it.

Calculate the liters-per-minute flow rate by dividing 60 seconds by the time recorded.

Alternatively, you can use a water flow gauge, also known as a weir gauge or cup, which is a device to measure the flow rate of water.

 

Choosing the right combi boiler for your properties water heating demands.

How much hot water you require is calculated by your domestic hot water fixtures, i.e., your quantities and types of hot water outlets you need to provide for; generally, how many bathrooms do you need to service? as these have the highest hot water demands.

Standard showers

Standard shower head 7 to 8 litres a minute flow rate

Standard shower head 7 to 8 litres a minute flow rate

Standard shower heads use 78 litres of hot water per minute at a temperature of 38°C to 40°C. Although the newer “green band” shower heads have a demand of 6 litres per minute, these are the current “ErP” (energy-related product) regulations that aim to reduce water consumption and thus save energy.

Drench showers

Drench showers with hot water flow rates from 15 to 30 litres a minute

“Drench” type showers can have extremely high flow rates, ranging from 15 litres per minute to almost any flow rate—30 litres is not unusual, for example.

Bath taps

Standard bath tap mixer type with a flow rate of around 12 litres per minute at full flow

Bath Tap – 12 L/Min Flow

Standard bath taps have a demand rate of around 12 litres per minute, again at 38°C to 40°C in temperature.

Other types of hot water taps

Standard washbasin taps have a flow rate of four litres per minute.

Kitchen sink taps: 4 to 6 litres per minute.

Washroom basin with “spray type taps”—2 litres per minute.

You may calculate your hot water demand by adding all of your prospective hot water outlets and then using a diversity factor (a variable that accounts for the fact that not all of the hot water outlets will be used simultaneously).

Example: You have two bathrooms or more in your large property—let’s call it three bathrooms, each fitted with a standard 7 L/min shower. For all three showers to be running at the same time, you will require 21 litres of domestic hot water flow to satisfy all the showers simultaneously in the winter period.

So can our boiler cope with two or more bathrooms ?Yes is the straight answer ! as long as you have the mains water flow rates to the home,and you have standard shower heads of 7 of 8 L/min.

Water temperature rise

The required temperature rise directly affects the amount of hot water a combi can produce.Domestic hot water bathing requires a temperature of around 40°C.

You want hot water the most in the winter period; generally, for most of the UK, 10°C is the coldest mains temperature in winter that we experience; however, for Scotland and Northern Ireland, this is 5°C.

Thus the temperature rise that is required for 40°C hot water (standard bathing temperature) is:

30°C for most of the UK – at this rise the boiler will produce – 23.4 L/min of DHW – which is enough hot water for 3 standard showers

35°C for Scotland and Northern Ireland – at this rise the boiler will produce – 20 L/min of DHW – which is enough hot water for 2 standard showers, plus some extra.

Our 50kW gas-fired combi boiler will produce:

Domestic hot water flow rates of our high flow rate combi boiler at various hot water temperature rises from Flexiheat UK

High domestic hot water flow rates from our 50kW gas fired combination boiler – at various temperature rises.

Combination boiler central heating output

The heating side of the combi boiler

A combi boiler also must provide heat for the central heating system, be it a radiator or underfloor heating system, just like a regular or system boiler does. Our 50 kW combi boiler can operate on an 80°C/60°C hot water flow and return temperature for existing high-temperature heating systems, producing a central heating output of 49.19 kW at this flow temperature of 80°C.

Now with wet heating systems to be designed with a maximum flow temperature of 55°C to lower running costs (energy bills) and reduce carbon emissions by running in a condensing mode continuously.When run at 50°C flow temperatures, the boiler will produce 53.40 kW of heat output for the central heating.

Or alternatively, the combi boiler can be used on lower flow temperature heating systems such as underfloor heating, which normally runs between 25°C to 45°C, as our combination boiler comes with a central heating output setting especially for underfloor heating systems, which limits the boiler output to a maximum of 45°C.This is one of the key features of our high hot water flow rate combi boilers.

Larger homes typically have a higher heating load compared to smaller homes. However, the benefit of our 50kW combination boiler is the larger boiler modulation rate, meaning our boiler is a great choice for smaller homes that have more bathrooms than normal or a high demand for hot water, as the heating side of the boiler will ramp down to 4.83kW on an 80/60C or 5.29kW at 50/30C of central heating output, which is exceptional performance—meaning you have the capability of providing hot water for three bathrooms and not an oversized boiler for the heating system, due to our boiler’s modulation rate. This high-output modulation feature makes our gas boiler one of the best combi boilers on the market.

 

Energy efficiency

Our 50kW unit is one of the best combi boilers on the UK market with

ErP “A” rated energy efficiency for heating and hot water, with up to 108.83% energy efficiency for this high flow rate combi boiler from Flexiheat UK, designed for multiple bathrooms properties.

With a warranty period of 5 years on the heat exchanger, as long as there is a high quality dirt and air separator fitted (it’s a requirement now as part of the building regulations for the UK) to the system and the combi boiler is serviced every year.

System Boiler vs. Combi Boiler

System boilers can offer higher flow rates than combi boilers, but require space for an indirect hot water tank.

System boilers are less affected by mains water flow rates, making them suitable for homes with low water pressure.

Combi boilers are ideal for homes with limited space, but may not be suitable for homes with very high hot water requirements.

Power Showers and Combi Boilers

Combi boilers cannot run power showers, as they require a boiler connected to a hot water cylinder.

Regular boilers are suitable for power showers but may not be as energy-efficient as combi boilers.

Power showers are not compatible with combi boilers because they operate with an in-built pump that needs to be connected to a hot water cylinder.

Contact Flexiheat UK

For the best highest flow rate combi boiler for homes and large properties with high hot water demand.Please contact our sales team on 01202 822221 to get the best deal or simply click on the following to use our site email contact form to get boiler quotes or for any technical boiler type queries.

Boiler low gas pressure

Boiler low gas pressure?

 

Boiler low gas pressure? Some boilers have problems with not having enough gas pressure. These problems aren’t always dangerous or common, but they can happen, especially in newer heating systems and result in low gas pressure to your boiler.

This is more noticeable when an installer or service worker goes to your home and finds that the gas pressure at the boiler’s intake is not high enough. Because of this, a Combi boiler won’t heat water to the same temperature and flow rate that it was made to do.  This problem often surprises homeowners because it can have a big effect on how well their hot water works, especially in the winter when the cold water coming from the mains is colder.

Why it can go wrong with different gas boilers

This problem isn’t as obvious with central heating because it needs less power. Most of the time, central heating systems are more forgiving because they don’t need as much immediate energy as combi boilers do to make hot water.

It’s also not as bad for regular or system heaters that store hot water in a cylinder. Even though it might take a little longer to heat the cylinder, the water temperature will still hit the right amount. In places where gas pressure problems are common, this can make them a safer choice. However, the right gas pressure should always be available.

A drop in gas pressure can cause combi boilers to produce less heat and water that isn’t hot enough, especially those that need higher outputs (30 to 40KW) to heat water right away. Users can be especially annoyed by this drop in performance, since combination boilers are advertised as being able to constantly provide hot water on demand.

How to fix boiler low gas pressure?

When low gas pressure is found, the gas engineer will usually check the gas pressure at the boiler’s inlet test point while it’s running at full capacity. This is a normal troubleshooting step that helps figure out what’s wrong. If the appliance’s inlet pressure isn’t high enough, the gas meter’s input pressure is checked.

If the pressure on the meter isn’t high enough, you should call the network gas supplier. It’s their job to investigate it and make any necessary changes to make sure all homes connected to the gas line have enough pressure. If the meter’s inlet pressure is good, on the other hand, it means that the gas supply pipes to the boiler is probably either too small or partly blocked. When you use Flexiheat UK boilers, the gas valve entry pressure needs to be between 16.5mb and 20mb. If the drop in hot water temperature is new and the boiler and hot water temperature were fine before, you might also want to check any filters that are attached to the boiler’s gas valve input. This can happen, especially if there has been work on the grid.

Gas pressure drop

Most of the time, the gap isn’t dangerous. Of course, the pressure drop would be small—maybe 3 or 4mb—rather than the usual 16.5 to 20mb at the boiler inlet. The operator might see 13 to 14mb. Even though this means the boiler isn’t working as well as it could, it will still work and fire safely.

Conclusion

One important thing for gas engineers to remember is to figure out where the low gas pressure is coming from, whether it’s in the property’s pipes or a problem with the outside gas mains network, and then fix the problem so the system works as it should. This could mean talking to other pros, like gas network engineers, or giving people advice on what system changes they need. Customers need to be told what happens when their gas pressure is low and how to fix it. This helps set realistic goals and makes sure safety standards are met.

Can I fit a waste or multi oil burner to my existing boiler?

Can I fit a waste or multi oil burner to my existing boiler?

Can I fit a waste or multi oil burner to my existing boiler by Flexiheat UK

Can I fit a waste or multi oil burner to my existing boiler ? by Flexiheat UK

A Kroll KG/UB waste or multi oil burner from Flexiheat UK is a great way to significantly reduce your heating costs. With its ability to burn almost any used oils from waste engine oils and hydraulic oils to used vegetables oils and Bio Diesel.  In fact, our range of waste/multi oil burners are so universal that they can also burn 100% rapeseed oil and heating oils. Because of these wonderful advantages, more and more people are looking to replace their existing oil burner with one of our KG/UB  waste / multi oil  burners.

Also, these burners are open to atmosphere and not a “sealed burner”– so aren’t suitable for being inside a property , as they will give off an “oil smell” – they should be used in an out house or out building as such.

Below, we have set out a variety of questions which should help you decide if a waste / multi oil burner is suitable to fit and work for your existing boiler.

1. Will the KG/UB waste / mutli oil burner fit onto my existing boiler?

Please check the dimensions, especially the dimensions of the “holes of the burner plate” and the “dimension of the burner tube”. If these dimensions correspond to the dimensions of the burner’s flame tube, the burner flange can be connected.

Please check the below paying particular detail to dimensions “E” and “G”. If the burner tube will fit and you can pick up the burner mountings (G) which have a range due to the slotted burner mounting flange

Download technical details of the KG/UB burners

2. The minimum combustion chamber diameter is 180mm – The minimum combustion chamber length must be

KG/UB20 Burner model = 320 mm

KG/UB55 Burner model= 360 mm

KG/UB70 Burner model = 360 mm

KG/UB100 Burner model = 380 mm

KG/UB150 Burner model= 400 mm

KG/UB200  Burner model = 400 mm

Download “Can I fit a kroll waste multi oil burner to my existing boiler” document 

3.Construction of your boilers combustion chamber;-

We have developed and patented our “ZVP” burner tube. This acts like another combustion chamber, within a combustion chamber, ensuring higher efficiency, better combustion, lower flue gas temperatures and longer maintenance periods.

 

ZVP Tube
The following picture shows one of our 200kW waste / multi oil burners with our ZVP tube attached

Waste / Multi Oil Burner

 

The ZVP burner tube ,which is attached directly to the burner comes with a ceramic mat for combustion chambers with convex rear as standard or a 500mm x 500mm ceramic fiber board for combustion chambers with a vertical rear panel

 Download drawing of combustion chamber variants

4. The Kroll waste/multi oil burners range require a compressed air supply.

This is neither a large amount of air (cfm) nor a high pressure (1.5 Bar Maximum). We  produce a whisper quiet compressor, which is extremely quiet and compact (roughly the size of a briefcase), this compressor is controlled by the burner, and is only in use when the burner has a demand. You can utilise your own compressor, as long as it meets the requirements of the burner, and you fit a good quality filter, regulator, water trap prior to the burner.

Whisper quiet air compressor for our waste and multi oil burners from Flexiheat UK

Whisper quiet air compressor for our waste / multi oil burners from Flexiheat UK

 

5. We would recommend that your existing flue system is at least, 4 meters, and includes an open terminal and a draught stabilizer is required. See below drawing of our recommended flue kit that is required.

Download recommended flue kit configuration for a waste oil boiler

For more information on our waste / multi  oil burner range, please click here  Alternatively, please give us a call on 01202 822222 and our dedicated sales team will be happy to offer advice and assistance or just contact us by email by clicking  here.