The Mixergy X Direct Slimline is a stainless steel unvented cylinder for electric-only properties, built into a narrower 475mm case for cylinder cupboards and loft hatches where width is restricted. It shares the same 2.0 Controller, WiFi connectivity and smart tariff compatibility as the standard-case Mixergy X.
Spanning 120 to 210 litres across four SKUs, the slimline case is taller than the standard case at equivalent capacity, but uses identical stratified thermocline smart charging to heat only the water volume actually required.
Please Note: Current Lead Times
Mixergy cylinders typically ship on a 3 to 6 week lead time, depending on model and quantity ordered. Please call us to check current availability before confirming an installation date.
Good to Know: Smart Tariff Compatible
The Mixergy app supports automatic scheduling against Octopus Agile, Octopus Go, EDF GoElectric Overnight, E.ON Next Drive and British Gas Heat Power tariffs.
Important: Unvented Installation Requirement
This is an unvented cylinder. Installation must be carried out by a G3-competent operative and commissioned per the manufacturer's Installation & Servicing instructions. Incoming mains pressure must be less than 10 bar and at least 1 bar, with a minimum flow rate of 10 L/min. Unvented cylinders must never be used with a solid fuel heat source.
Slimline 475mm Case
Purpose-built for restricted cylinder cupboards or loft hatches, trading additional height for a narrower footprint versus the 550mm standard case.
Stratified Smart Charging
Thermocline sensors mean the controller only heats the volume of water required, giving fast top-ups from as little as 32 minutes rather than a full reheat.
Electric-Only Design
Purpose-built for properties without a gas or oil boiler, using the 3kW immersion heater as the sole heat source, ideal for off-peak and time-of-use tariffs.
Full App Control & Monitoring
The bundled WiFi dongle connects to the Mixergy app for remote boost, live charge-state monitoring, and voice control via Google Assistant or Amazon Alexa.
Low Standing Heat Loss
50mm CFC/HCFC-free polyurethane foam insulation keeps standing heat loss low across the range despite the taller, narrower profile.
Safety-Certified Components
Factory-fitted monobloc cold water inlet control group, T&P relief valve (7 bar/90°C), and expansion vessel charged to 3 bar.
Controller & Electrical
| Controller generation |
2.0 Controller |
| Immersion heater rating |
3kW, 230–240V~ |
| Immersion heater specification |
EN 60335-2-73, 356mm Incoloy |
| Electrical supply |
16A, dedicated MCB-protected circuit |
| Thermostat safety cut-out |
80°C |
| Adjustable temperature range (digital) |
50–65°C |
| Connectivity |
WiFi dongle (supplied) or hardwired Ethernet |
Unvented Safety Components
| Max. supply pressure to PRV |
10 bar |
| Operating pressure |
3 bar |
| Expansion vessel charge pressure |
3 bar |
| Expansion relief valve setting |
6 bar |
| T&P relief valve setting (pressure) |
7 bar |
| T&P relief valve setting (temperature) |
90°C |
Construction
| Cylinder material |
Stainless steel |
| Insulation type |
CFC/HCFC-free polyurethane foam |
| Insulation thickness |
50mm |
| Connection size/type |
22mm compression |
Model Range
| Model Code |
Capacity |
ErP |
Height |
Weight Full* |
Std. Heat Loss |
Min Reheat |
| MX-120-ELE-475 |
120L |
B |
1247mm |
143kg |
1.25 kWh/24h |
32 mins |
| MX-150-ELE-475 |
150L |
B |
1518mm |
173kg |
1.42 kWh/24h |
32 mins |
| MX-180-ELE-475 |
180L |
B |
1790mm |
208.4kg |
1.51 kWh/24h |
32 mins |
| MX-210-ELE-475 |
210L |
B |
1962mm |
231.4kg |
1.58 kWh/24h |
32 mins |
What is the difference between the slimline and standard case?
Both share the same controller, insulation and connections. The slimline case is 475mm diameter but taller at equivalent capacity, for restricted cupboard or loft hatch installations; the standard case is 550mm diameter.
Does the Mixergy X need an internet connection to work?
No — the cylinder heats and operates normally without WiFi. An internet connection unlocks the app features: remote control, smart tariff scheduling, and usage monitoring.
What does the weight full* figure account for?
Add 5kg to the full cylinder weight shown for cylinders fitted with an external heat exchanger.
What certification does the installer need?
Installation must be carried out by a competent operative who has completed a recognised unvented hot water systems course, with commissioning recorded per Building Regulations (G3) requirements.
What is included in the box?
Each cylinder ships with the monobloc cold water inlet control group, expansion vessel with mounting bracket, factory-fitted immersion heater(s), WiFi dongle, Ethernet cable, gauge, and user guide.
How long is the lead time and how do I check stock?
Lead times typically run 3 to 6 weeks depending on model and order quantity. Please call us to confirm current stock and expected delivery before booking an installation.
