FAQs

Question 1

Heat Interface Unit (HIU) efficiency

Accepted Answer

Using a twin plate HIU (indirect Heating & Domestic Hot Water) as an example, there are a few ways in which product efficiency can be measured. Read more..

Question 2

Heat Interface Unit (HIU) pros and cons

Accepted Answer

Find out the pros and cons of Heat Interface Units (HIUs) here at Baxi FAQs...

Question 3

How to reset pressure on my Heat Interface Unit (HIU)?

Accepted Answer

Watch this video to find out how  to reset pressure on my Heat Interface Unit (HIU)...

Question 4

What is the price of a HIU (Heat Interface Unit)?

Accepted Answer

Average cost for a Heat Interface Unit (HIU) can be from around £800 to £1500, depending on the HIU type, performance of the unit and equipment provided.

Question 5

What support is available in the design of my system?

Accepted Answer

Our Application Engineers can assist in advising clearances, dimensions, and possible locations for consideration. Find out more...

Question 6

What support is available for installation / set up of the Heat Interface Unit (HIU)?

Accepted Answer

Baxi’s technical helpline supports you at every step of your installation & commissioning process. Find out more about training & enhanced warranty here.

Question 7

How often does a Heat Interface Unit (HIU) need servicing?

Accepted Answer

Heat Interface Units (HIUs) have an annual maintenance requirement to ensure safe working and optimum performance. Find out more...

Question 8

Are the Baxi AquaHeat HIUs compatible with our range of boilers, water heaters and cylinders?

Accepted Answer

At Baxi we have a broad range of products to help meet our customers needs. Find out if HIUs are compatible with Boilers, water Heaters, & Cylinders here.

Question 9

Does the Baxi AquaHeat range come with any remote monitoring or control capabilities?

Accepted Answer

Yes, all Baxi AquaHeat models are compatible with our Baxi Data Management, Mercurius platform. Find out more about all the functionality it has to offer.

Question 10

What type of control system is used on the Baxi AquaHeat range?

Accepted Answer

Baxi AquaHeat HIUs contain a full electronic control system, using our in-house designed TR-04 controller. Some Key Functions can be found here...

Question 11

In what lead time are the Baxi AquaHeat range products available?

Accepted Answer

Baxi AquaHeat range & associated accessories & controls are available on an 8-week lead time. Baxi can also manage a phased delivery depending on project.

Question 12

What accessories do I need for my Heat Interface system?

Accepted Answer

The full list of compatible accessories required for your Heat Interface system can be found here...

Question 13

What is VWART?

Accepted Answer

VWART stands for Volume Weighted Average Return Temperature. Read more about it in our Baxi FAQ section...

Question 14

What approvals and certification does the Baxi AquaHeat range hold?

Accepted Answer

Baxi AquaHeat range of Heat Interface Units (HIUs) are all compliant with UK Water Regulations & Bylaws, with the certification carried out by NSF. Read more

Question 15

What primary (Heat Network) conditions are the AquaHeat HIUs suitable for operating at?

Accepted Answer

The AquaHeat range of HIUs can operate with primary temperatures from the Heat Network up to 90°C and maximum primary operating pressures of 16 bar.

Question 16

What temperatures can the Baxi AquaHeat Heat Interface Units (HIUs) operate at?

Accepted Answer

The Baxi AquaHeat Heat Interface Unit (HIU) range can provide space heating from 15 to 85°C. The AquaHeat HI / HWI models can provide DHW from 40 to 65°C.

Question 17

What outputs are the Baxi AquaHeat range available in?

Accepted Answer

Baxi AquaHeat HI/HWI is available in two different outputs, available with or without a Heat Meter and the Mercurius connected module factory fit. Read more

Question 18

What types of HIU are available as part of the Baxi AquaHeat range?

Accepted Answer

With two models, the Baxi AquaHeat Heat Interface Unit (HIU) range can meet the needs of most apartment building developments. Find out more...

Question 19

What applications are Heat Interface Units (HIUs) suited for?

Accepted Answer

Through these various product types, HIUs are suitable for residential and commercial applications as well as providing heat for communal spaces. Read more

Question 20

Does a Heat Interface Unit (HIU) use gas or electricity?

Accepted Answer

There is no gas connection required with an Heat Interface Unit. Energy required for heating and hot water is taken from the heat network. Find out more...

Question 21

How does an HIU work?

Accepted Answer

FAQ Description/Answer Here

Question 22

What is a Hydraulic Interface Unit (HIU)?

Accepted Answer

Find out what an Hydraulic Interface Unit or HIU is at our Baxi FAQ's section...

Question 23

What is a Heat Network?

Accepted Answer

Find out what heat networks are and different types of heat networks at our Baxi FAQ's section...

Question 24

What is the Boiler Upgrade Scheme (BUS)?

Accepted Answer

Find out what Boiler Upgrade Scheme (BUS) is and how it works at Baxi FAQs section...

Question 25

Who needs to know, when installing an air source  heat pump?

Accepted Answer

Who needs to be informed when installing an Air Source Heat Pump? Find out the lost of people/authorities here...

Question 26

Do I have to be Gas Safe registered to install an air  source heat pump?

Accepted Answer

A competent knowledge in plumbing and heating is all that is needed as a prerequisite for the NVQ Level 3 Heat Pump Installation qualification. Read more...

Question 27

Do I have to be F-Gas certified to fit an ASHP?

Accepted Answer

Monobloc style air source heat pumps contain a hermetically sealed refrigeration circuit and do not require F-Gas certification to install.

Question 28

Why such a big push to install air source heat  pumps now?

Accepted Answer

Find out why there is such a big push to install Air Source Heat Pumps now...

Question 29

What is a monobloc air source heat pump (ASHP)?

Accepted Answer

Monoblocs are self-contained heat generators. All the hydronic, refrigeration & electrical components are inside the casing, similar to a boiler. Read more

Question 30

How do I connect My Baxi app to my Alexa?

Accepted Answer

Learn how to connect My Baxi app to Alexa. Once you've linked your uSense to Smart Home device, you can ask Alexa to announce or set the Room Temperature.

Question 31

What are the different hot water settings and how do I change them?

Accepted Answer

Learn the different hot water settings and how to change them at Baxi FAQ section here...

Question 32

How do I set up holiday mode?

Accepted Answer

During Holiday mode, the heating temperature will be set to ‘anti-frost’ to protect your home from frozen pipes in cold weather. Learn how to get started.

Question 33

How can I set the schedule for my central heating?

Accepted Answer

The existing central heating schedules should have been migrated over from your old uSense app. If you need to change them, follow the instructions here...

Question 34

How can I set the temperature for my hot water?

Accepted Answer

Want to set the temperature for hot water? Here are the instructions. Remember to set between 50-60 degrees Celsius for a combi boiler. Find out more here.

Question 35

How do I refresh the dashboard page on the app?

Accepted Answer

Want to refresh the dashboard page on the My Baxi app? Pull down the home screen until the ‘refresh’ icon appears.

Question 36

How long does a boiler last?

Accepted Answer

Find answers to how long does a boiler last, when does a boiler need replacing, and how you can make my boiler last longer here...

Question 37

How long is the warranty on a Baxi boiler?

Accepted Answer

Find answers to Boiler warranties, warranty cover, if warranties can be transferrable and how a Baxi boiler warranty work here at Baxi FAQs...

Question 38

How do I set up my new My Baxi app for my uSense smart control?

Accepted Answer

All the information on your old uSense app should be migrated automatically on My Baxi app. Simply follow the steps or watch our video to complete setup.

Question 39

What happens at a boiler service?

Accepted Answer

Make sure the installer who carries out your service is Gas Safe registered. Find out what the engineer will check for and how long the service takes...

Question 40

Do I need a carbon monoxide detector fitted?

Accepted Answer

For you and your family's safety, it is advisable to fit a carbon monoxide alarm in each room in your home that has a gas appliance or solid fuel heating.

Question 41

Are there grants available for heat pumps?

Accepted Answer

Different areas may offer different grants to help you with the cost of installing an air source heat pump. Find out if you are eligible on this page.

Question 42

Can I still replace my old gas boiler?

Accepted Answer

Yes, you can replace your existing gas boiler but you don’t have to do this before 2025. Find out more at Baxi's FAQ section...

Question 43

What is the Boiler Upgrade Scheme?

Accepted Answer

Find out everything you need to know about Boiler Upgrade Scheme and if you eligible for the Boiler Upgrade Scheme.

Question 44

Should I turn off my boiler in the summer?

Accepted Answer

Is it ok to turn off your boiler in summer? The short answer is: it depends on your home and your circumstances. Find out more...

Question 45

Why should I have a filter fitted?

Accepted Answer

Many boiler breakdowns occur are due to sludge in the heating system. Find out the many benefits of fitting a magnetic filter & how it can save you money.

Question 46

Why should I get the water in my central heating system cleaned?

Accepted Answer

If Boiler breaks down due of sludge in the system, the repair work is not covered by the Boiler warranty & can lead to expensive repair bills. Read more...

Question 47

Why are my radiators cold?

Accepted Answer

Not sure why your radiators cold at the top or bottom? Find out the reasons and simple solution to resolve this.

Question 48

What is central heating sludge?

Accepted Answer

Sludge or magnetite if left to build up, can damage the boiler and the heating system. Find out everything you need to know about Sludge here...

Question 49

What is a magnetic boiler filter?

Accepted Answer

Find out everything you need to know about the magnetic boiler filter, how they function, why should the filter be fitted, and how to look after them.

Question 50

How do I know if I've got sludge in my central heating system?

Accepted Answer

Find out if there is sludge in my central heating system with these common signs. As the installer to check for sludge during your annual boiler service.

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FAQs

Heat Interface Unit (HIU) efficiency

Heat Interface Unit (HIU) pros and cons

How to reset pressure on my Heat Interface Unit (HIU)?

What is the price of a HIU (Heat Interface Unit)?

What support is available in the design of my system?

What support is available for installation / set up of the Heat Interface Unit (HIU)?

How often does a Heat Interface Unit (HIU) need servicing?

Are the Baxi AquaHeat HIUs compatible with our range of boilers, water heaters and cylinders?

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