The Mixergy Solar X Indirect Slimline combines a boiler-fed primary coil with a factory-fitted embedded PV diverter, built into a narrower 475mm case for restricted cylinder cupboards and loft hatches.
Spanning 120 to 210 litres across four SKUs, this model shares the same 2.0 Controller, embedded diverter modulating between 30W and 3000W, and stratified thermocline smart charging as the standard-case Solar X Indirect.
30W–3000W
Modulation Range
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: Solar Surplus, Automatically Used
The embedded diverter continuously modulates output between 30W and 3000W, matching the immersion load to whatever solar surplus is available at any given moment.
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.
Factory-Fitted PV Diverter
The diverter ships embedded and pre-wired at the factory, cutting installation time and eliminating a separate wall-mounted diverter unit.
Boiler-Fed with Solar-Boosted Backup
Heated primarily via the internal coil from a gas, oil or LPG boiler, with the immersion backup topped up by diverted solar surplus.
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.
Coil Output for Every Size
Coil ratings from 17.8kW to 19.9kW across the range support fast boiler-fed reheats even at the taller 210L 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.
Embedded Solar Diverter
| Thermostat cut-out temperature |
80°C |
| Immersion heater(s) rating |
230–240V~, 2.7–3.0kW |
| Immersion heater(s) specification |
EN 60335-2-73 |
| Immersion heater(s) type |
356mm Incoloy/Ti |
| Modulation range |
30W–3000W |
Controller & Electrical
| Controller generation |
2.0 Controller |
| Electrical supply |
16A, dedicated MCB-protected circuit |
| 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-120-IND-475-PVE |
120L |
B |
1247mm |
17.8kW |
146.6kg |
11 mins |
| MX-150-IND-475-PVE |
150L |
C |
1518mm |
18.3kW |
180.4kg |
11 mins |
| MX-180-IND-475-PVE |
180L |
C |
1790mm |
19.4kW |
214.8kg |
11 mins |
| MX-210-IND-475-PVE |
210L |
C |
1962mm |
19.9kW |
247kg |
11 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.
How does the embedded PV diverter work alongside the boiler coil?
The boiler coil provides the primary heating; the embedded diverter separately routes solar surplus into the immersion element, modulating between 30W and 3000W.
What is the difference between the slimline and standard case?
Both share the same controller and diverter. The slimline case is 475mm diameter but taller at equivalent capacity; the standard case is 550mm diameter.
Can the Solar X Indirect Slimline 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, with the PV diverter continuing to serve the immersion element.
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.
