Joule Invacyl Slimline Direct Unvented 150L Cylinder
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The Joule Invacyl Slimline Direct Unvented 150L Cylinder is a slim-profile stainless-steel hot water cylinder engineered for unvented mains-pressure systems. With a 150-litre capacity, it provides reliable hot water to multiple outlets while helping maximise available floor and plant-room space. Manufactured from LDX 2101 stainless steel and insulated with dense 50mm PU foam, the cylinder is designed for durability, efficient heat retention and dependable hot water performance in family homes, renovation projects and small commercial installations.
Applications & suitability
Family homes
The 150-litre capacity is suited to family-sized households requiring reliable mains-pressure hot water for multiple outlets.
Renovation & retrofit
The slimline profile helps maximise available floor space, making the cylinder suitable for renovation and retrofit projects where space is limited.
Multiple outlets
Designed for applications where showers, taps and appliances may require dependable hot water supply at the same time.
Small commercial settings
Suitable for small commercial or office installations with moderate hot water demand and a requirement for mains-pressure hot water.
Key specifications
| Product details | |
| Product model | Joule Invacyl Slimline Direct Unvented 150L Cylinder |
| Actual capacity | 150 L |
| Unit weight empty | 33 kg |
| Unit weight full | 177 kg |
| Cylinder material | LDX 2101 stainless steel |
| Outer casing | Coated mild steel |
| Thermal insulation | Dense PU foam |
| Foam thickness | 50 mm |
| No. of immersions | 2 |
| Immersion specification | 3 kW @ 230 V |
| Maximum mains water pressure | 10 bar |
| Operating pressure (T & P) | 7 bar |
| Safety temperature | 90°C |
| Heat loss | 1.61 kWh/24h |
| Tested to standard | BS EN 50440:2015 |
| Warranty | 25 years |
Installation & compatibility
The Joule Invacyl Slimline Direct Unvented 150L Cylinder is engineered for unvented mains-pressure hot water systems. Its slimline construction is designed to help make efficient use of available installation space, while the 150-litre capacity provides hot water for multiple outlets. The cylinder is suitable for residential, renovation, retrofit and small commercial applications where reliable mains-pressure hot water is required.
Design & performance benefits
Slimline space-saving design
The slim-profile cylinder is designed to maximise available storage and installation space, making it suitable for locations where floor area is limited.
Stainless steel construction
Manufactured using LDX 2101 stainless steel, the cylinder is designed to provide corrosion resistance and long service life.
Efficient insulation
Dense 50mm PU foam insulation helps reduce heat loss, with a specified heat loss of 1.61 kWh/24h.
Dual immersion heaters
Two 3 kW immersion heaters operating at 230 V provide the cylinder with a direct heating arrangement designed to support fast recovery times.
Additional features
High pressure capability
Supports mains water pressure up to 10 bar, with an operating pressure of 7 bar for dependable hot water delivery to multiple outlets.
Protected outer casing
The coated mild steel outer casing provides additional protection while giving the cylinder a neat and durable external finish.
Safety performance
Designed with a specified safety temperature of 90°C and tested to BS EN 50440:2015.
Ideal for
The Joule Invacyl Slimline Direct Unvented 150L Cylinder is ideal for family homes, multi-occupancy properties, renovation and retrofit projects, and small commercial or office installations requiring reliable mains-pressure hot water. Its slimline construction helps make efficient use of limited floor space, while the 150-litre capacity and dual 3 kW immersion heaters provide a practical solution for installations serving multiple showers, taps and appliances. With LDX 2101 stainless steel construction, 50mm PU foam insulation, high pressure capability and a 25-year warranty, it is designed for dependable long-term hot water performance.
At GetPlumb, we strive to provide reliable and cost-effective delivery options to our customers. Please review our shipping policy below.
🆓 Free Local Delivery (Orders £100 & above)
We offer FREE delivery on orders £100 or more
for selected local areas.
Eligible Postcodes Include:
- RG*
- SL*
- OX10*, OX11*, OX49*
- HP1*, HP3*, HP8*, HP9*, HP10*, HP11*, HP12*, HP13*, HP14*
- WD*, HA*, UB*, TW*, KT*
- W1* – W9*
- NW*, SW*
Delivery Time: 2–4 working days
Shipping Cost: £0.00
📦 Standard Shipping (Weight-Based Rates)
For orders that do not qualify for free delivery, standard
shipping rates apply based on total cart weight.
- For cart weight between 0–2 kg, the shipping cost is £4.50 with a delivery time of 2–4 working days.
- For cart weight between 2–24 kg, the shipping cost is £9.99 with a delivery time of 2–4 working days.
- For cart weight between 24 kg and above, the shipping cost is £60 with a delivery time of 2–4 working days.
🧱 Block Salt (Harvey’s) – Unit-Based Shipping
This rate applies only to Harvey’s block salt products.
- £7.99 is charged for every 3 items.
- The charge increases by £7.99 for each additional set of 3 items.
Examples:
- 1–3 items → £7.99
- 4–6 items → £15.98
- 7–9 items → £23.97
Delivery Time: 2–4 working days
📏 Large / Long Items (Length-Based Shipping)
For oversized items where the product length is 1.5 metres or more:
Conditions:
- Product length ≥ 1.5 m
- Cart weight ≤ 40 kg
Shipping Cost: £18.00 (flat rate)
Delivery Time: 2–4 working days
Collection from Store
Customers can also choose to collect their order from our store in
Reading, UK, at no additional charge. For any questions regarding shipping, please contact our support team at online@getplumb.co.uk.
