See if you have a time controller on your system or if it just on and off at the boiler. Controlling your system by turning the boiler on an off could indicate a gravity system.

The final component, the smart radiator thermostat, is a white plastic cylinder, which fit to the radiator once the existing valve has been unscrewed. To manually override any schedules you may have set, simply swivel the top of the radiator thermostat right to start the radiator heating, or left to stop heating. An LED on the radiator thermostat glows red temporarily when the radiator is heating, and blue if it's been turned off. Turning and holding the radiator thermostat will also reset or put it into set-up mode, depending upon how long you hold it in that position. This type of system is effectively an upgraded gravity-fed system, where the central heating has been upgraded to be fully pumped, while the hot water remains gravity-fed. This type of upgrade allows separate central heating and hot water timer control, unlike standard gravity-fed systems, due to the addition of motorised valves and a cylinder thermostat. CHARACTERISTICS OF CONVENTIONAL BOILERS (with vented hot water and fully pumped)If you have a gravity-fed system, Wiser will only be compatible if it is fully pumped, by that we mean upgraded with motorised valves and a cylinder thermostat. A distinctive feature of a gravity-fed system is four 22mm or 28mm copper pipes connected to the boiler (sometimes three pipes if an injector T is fitted, but a fourth 22mm or 28mm copper pipe will still be nearby). Powered by two AA batteries, the smart thermostat can be freestanding on a table or shelf, or mounted on a wall. It has three touch controls on the front. The plus and minus button allow you to adjust the desired temperature of the room, while the middle button boosts the heating in said room by two degrees. The screen automatically goes to sleep after 15 seconds to conserve the battery, but pressing any of the three touch controls will wake it up. Gravity-fed systems are no longer fitted new and do not comply to current building regulations, therefore homeowners are increasingly opting to replace older gravity-fed systems to either combi or fully-pumped conventional boiler systems. CHARACTERISTICS OF GRAVITY-FED SYSTEMS (non-pumped)

HubR: User: Push Button/LED; I/O: Mains Relays (1-3), Digital Boiler Interface; Room thermostat: User: TFT display, touch buttons; I/O: None; Radiator thermostat: User: Twist Cap, LED; I/O: None The Insights tab includes information on how much energy you’ve saved with Eco mode enabled, while also presenting a ‘Heat Report’ that details how long and to what temperature over the past day, week, and month your rooms have been heated. Consists of a central heating boiler and a separate, pressurised hot water tank fed directly by the cold water mains feed, so the tank heats and stores hot water at mains pressure.If, however, but turning on the central heating side, the hot water also turns on, this would indicate a gravity system. ADVANTAGES OF CONVENTIONAL BOILERS (with vented hot water and fully pumped) A system that was originally fully gravity-fed that has been upgraded/retrofitted with motorised valves, such that the central heating is now fully pumped - a recommended upgrade if full replacement of an older gravity-fed system is not possible. On the 2-channel programmer where you set your schedules, try setting the hot water side to off and the central heating side to on. If doing this automatically turns on the hot water side as well, this would indicate a gravity system. ADVANTAGES OF GRAVITY-FED SYSTEMS (non-pumped) We also found it was easy to create some basic automations in the app using the Moments feature - such as turning the radiators in the lounge on, while also dimming the map connected to the Wiser smart plug to create a cozy atmosphere of an evening. App

Now that we’re clear what a combi boiler is, some combi boiler systems have two separate heating zones, controlled by two thermostats. CHARACTERISTICS OF COMBI BOILERS (two heating zones) With its intuitive user interface, the Wiser Home app makes it easy to adjust your room thermostat and radiator thermostats. Set up your app in seconds using simple step-by-step instructions. The Heat Hub is a rectangular box with two buttons. One button activates the set-up process, while the other starts the whole system heating. LEDs above the buttons glow green when these options are active. The Heat Hub should be screwed to the wall next to your boiler. The square smart thermostat has a two-inch screen that shows the current temperature of the room it’s in, as well as the desired temperature. It also displays the relative humidity and battery level, and features a flame icon to indicate if the heating is switched on. Older systems upgraded with pumps provide better thermostatic control of the central heating and the ability to control it independently of the hot water.We did notice a slight delay of around 10 seconds to one minute between boosting the heating from both the radiator thermostat or the app and the boiler springing into action. The further away from the Heat Hub the thermostat is, the longer the delay. Initially, we also struggled to get the radiator thermostat in the room furthest from the Heat Hub to remain connected to the system at all times. It would often drop the signal, meaning we were unable to control it via the app. However, after installing an optional Wiser Smart Plug – which also doubles as a range extender for the system – in a room between the Heat Hub and the troublesome radiator thermostat, connection issues were no longer a problem. Wiser thermostat and multi-zone kits 2 and 3 may be compatible with gravity-fed systems that have been retro-fitted or upgraded with pumps and cylinder thermostats - Please speak to our Technical Support Helpline on 0333 6000 622 for further advice on your system’s compatibility. Also known as sealed or system boiler systems, a conventional boiler system with an unvented hot water cylinder uses a hot water cylinder that’s separate to the boiler but does not require a cold water tank usually typical of vented gravity-fed systems. CHARACTERISTICS OF CONVENTIONAL BOILERS (with unvented cylinder and one heating zone) Wiser smart thermostats are compatible with most boiler makes and models, but it’s important to consider which boiler system type you have when selecting your Wiser kit. Here we’ll guide you through the most common boiler system types to help you find the ideal Wiser products to suit your home. Also try our online Product Selector to find the right kit in just a few short steps.