How to Program a Megaflo Direct Cylinder Timer in Horsham, West Sussex

July 2026 Horsham Mend Your Home DIY/Owner Knowledge

Struggling with high energy bills from your hot water cylinder? In this guide, we walk you through a recent job in Horsham where we helped a customer program their Megaflo direct cylinder. Learning how to properly use your off-peak timer can save you hundreds of pounds a year on electricity.

What is a Direct Cylinder?

If you have a Megaflo direct cylinder, it means you don't have a boiler heating your water. Instead, you have two immersion heaters built directly into the cylinder. Think of them exactly like the element inside a kettle. They use electricity to boil the water inside the tank.

Because they use direct electricity, they can be quite expensive to run if they are left on 24/7. That's why setting up off-peak programming is absolutely crucial.

Step 1: Check Your Electrical Tariff

Before programming your timer, you need to know when your electricity is cheapest. This is called your "off-peak" rate (like Economy 7 or Economy 10).

Pro Tip: Contact your electrical supplier. They will tell you exactly what hours your off-peak rate applies (e.g., usually between 1:00 AM and 5:00 AM or 1:15 AM and 8:00 AM depending on your plan). If you are on a fixed single-rate tariff, you won't have an off-peak period, but you can still use the timer to only heat water when needed.

Step 2: Setting the Off-Peak Timer

Once you know your cheap hours, you can program the Megaflo timer (the small digital box connected to your cylinder).

Set the Clock: Ensure the time on the programmer is correct. Use the directional buttons to move over the options and press 'Select'.
Go to Off-Peak Programming: Navigate to the off-peak section.
Set the On Time: Program the timer to turn ON at the start of your cheap rate (e.g., 1:15 AM).
Set the Off Time: Program it to turn OFF around 8:00 AM (or whenever your cheap rate ends).

The cylinder has a built-in thermostat. If the water gets hot enough before 8:00 AM, it will automatically turn itself off so you don't waste energy!

Step 3: Using the Boost Function

What happens if you run out of hot water in the middle of the afternoon when electricity is most expensive? That is what the Boost Function is for.

For example, if you know you need to wash dishes and have evening showers around 7:00 PM, you can set the Boost timer to come on at 5:30 PM. It generally takes about half an hour to an hour for the immersion heater to boil the water. You can also manually hit the physical "Boost" button on the timer anytime you need a quick top-up outside of your normal scheduled hours.

Need Help with Your Heating in Horsham?

If your Megaflo isn't heating properly, or you need a professional to inspect your hot water cylinder, Mend Your Home is here to help.

Call: 07960 066300 Request Callback