Frequently Asked Questions (FAQs)

  • When should I get my appliance serviced?
  • If I need a visit from a Heatrae Sadia engineer, who can I contact?
  • Where can I obtain a spare part for my Heatrae Sadia product?
  • Can you send me literature on a Heatrae Sadia product?
  • Where can I get a copy of the installation instructions and user manual for my product?
  • Where can I receive training for Heatrae Sadia products?
  • Where can I go to meet the Heatrae Sadia team?
  • I have a technical question on a Heatrae Sadia product, can you help?
  • How do I regenerate the airgap on my Megaflo?
  • What size cylinder would you recommend for my property?
  • Can I fit plastic pipework to a Megaflo?
  • Do you suggest using a water softener for a Megaflo?
  • Can I install a Megaflo in the basement?
  • Would you suggest using a timer for a Supreme?
  • Can I use a Streamline for two or three sinks?
  • Do I need an expansion kit for a Multipoint?
  • Can I use a vented unit with an expansion kit (vessel and relief valves)?
  • Which engineers can work on my unvented system or can I work on it myself?
  • What qualifications does my engineer need to install an unvented appliance?

We recommend all our appliances are serviced annually. Contact our customer support team on +44 (0)344 871 1535 to book an appointment.

Our Customer Support team provide Heatrae Sadia's aftersales service. To arrange a visit please call +44 (0)344 871 1535.

All enquiries received by our Customer Service Centre 0344 871 1535 are directed to one of our approved stockists. Heatrae Sadia does not sell spare parts directly to installers or the general public. Find your nearest stockist from our dedicated genuine parts partner.

You can contact our Literature Hotline on 0344 871 1535 or download literature from the Literature library or relevant product page on our website.

These can be ordered through our literature hotline on 0344 871 1535 or downloaded by the Literature library or relevant product page on our website.

We have a number of training centres around the country, offering an excellent standard of training on our products. Find out more about our centres and the courses they offer on our Training pages. 

We attend a number of exhibitions and events during the course of the year. Find out about our upcoming events on our News & events website page.

The Customer Support team can be reached on +44 (0)344 871 1535.  We have a number of experienced engineers who will be able to answer your query.

To re-charge the air gap please use the following simple instructions:

  • Turn off the mains cold water supply to the Megaflo
  • Open the lowest hot tap in the property
  • Hold open the temperature / pressure relief valve until the gurgling noise stops and water stops running from the tap and valve
  • Close the temperature / pressure relief valve; open the mains cold water supply to the Megaflo. When water flows from the hot tap close the tap
  • If water continues to drop or flow from the overflow the Megaflo requires attention. Switch off heat soures (immersion heaters and boiler), DO NOT turn off water supply. Contact a competent install for advice. Watch a video that demonstrates who to replenish the air-gap on a Megaflo cylinder.


Our specification team can give you all these details, they can be contacted on 0344 871 1535 or by email at

Yes you can providing the pipework is suitably rated to the application.

You can use a water softener with a Megaflo if you so wish but this must not be detrimental to the incoming flow rate, and the softened water must not exceed a chloride value of 250 mg/litre.

A Megaflo can be sited anywhere in your property but the installation of the discharge pipework has to be taken in to account when deciding on where to install the unit.

Yes, you can use a timer for this and it can be ordered as an accessory to the Supreme, download the Supreme brochure for more information.

No, the unit is designed to work with one tap outlet only.

This would depend on the type of application the unit is being used for.  Please contact our technical team on +44 (0)344 871 1535 for further details.

No, this would not apply to building regulations and goes against the manufacturers installation instructions which would invalidate your warranty.

We would always recommend a suitably qualified engineer carries out any necessary servicing and repairs on your unvented system. Contact us for more information.

You will need a plumber or heating installer who is fully qualified and competent to install unvented products. In England and Wales, check your installer has a G3 unvented qualification - they will have a registration card to prove they have obtained the necessary qualifications. The equivalent for Scotland is P3 and for Northern Ireland it is P5.

Related information

Our factory compliance standards

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