The Mixergy X Indirect Standard is a stainless steel unvented cylinder heated via an internal primary coil from a gas, oil or LPG boiler, with immersion backup and the 2.0 Controller for smart control. Every unit ships with WiFi connectivity and full compatibility with smart electricity tariffs for the immersion backup element.
The 550mm standard case spans 150 to 300 litres across five SKUs. Stratified thermocline sensing means the controller only heats the water volume actually needed, delivering minimum reheat times as fast as 11 minutes from the boiler coil.
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.
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.
Stratified Smart Charging
Thermocline sensors mean the controller only heats the volume of water required from the boiler coil, giving minimum reheat times as fast as 11 minutes.
Boiler-Fed with Immersion Backup
Heated primarily via the internal coil from a gas, oil or LPG boiler, with the 3kW immersion heater available as backup or for smart-tariff top-ups.
550mm Standard Case
The full-diameter case gives maximum capacity per unit height, suiting cylinder cupboards without width restrictions.
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.
High Coil Output
Coil ratings from 18.3kW to 23.6kW across the range support fast boiler-fed reheats even at the largest 300L capacity.
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 |
| Coil max. working pressure |
3.5 bar |
Construction
| Cylinder material |
Stainless steel |
| Insulation type |
CFC/HCFC-free polyurethane foam |
| Insulation thickness |
50mm |
| Connection size/type |
22mm compression |
| Coil max. working pressure |
3.5 bar |
| Diverter valve (>70°C boilers) |
Honeywell V4043H1056 2-port, or equivalent |
Model Range
| Model Code |
Capacity |
ErP |
Height |
Coil Rating |
Weight Full |
Min Reheat |
| MX-150-IND-550 |
150L |
B |
1117mm |
18.3kW |
178.2kg |
11 mins |
| MX-180-IND-550 |
180L |
B |
1305mm |
19.4kW |
212.2kg |
11 mins |
| MX-210-IND-550 |
210L |
B |
1493mm |
19.9kW |
245.2kg |
12 mins |
| MX-250-IND-550 |
250L |
C |
1743mm |
20.7kW |
289.8kg |
12 mins |
| MX-300-IND-550 |
300L |
C |
1989mm |
23.6kW |
344.6kg |
12 mins |
Please Note: Indirect Installations Over 70°C
Where the boiler or primary heat source is capable of exceeding 70°C, the supplied 2-port diverter valve (Honeywell V4043H1056 or equivalent) must be fitted, per the manufacturer's Installation & Servicing instructions.
What is the difference between Direct and Indirect models?
Indirect models heat water via an internal coil from a gas, oil or LPG boiler, with the immersion heater as backup. Direct models heat via immersion only.
Does the Mixergy X Indirect need an internet connection to work?
No — the cylinder heats and operates normally without WiFi. An internet connection unlocks app features such as remote control, smart tariff scheduling, and usage monitoring for the immersion backup.
Can the Mixergy X Indirect be used with a heat pump instead of a boiler?
Yes. The controller supports a heat pump heat source setting in place of a boiler, and cylinders have dedicated heat pump-ready ports. An optional plate heat exchanger is available.
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.
