
Stiebel Eltron MAG 12 Expansion Vessel
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The Stiebel Eltron MAG 12 is a high-quality expansion vessel designed to manage pressure fluctuations within your heating or cooling system. Essential for maintaining system integrity, this robust accessory prevents damage caused by thermal expansion, ensuring your Stiebel Eltron heat pump or air conditioning setup operates safely and efficiently. Its compact design allows for straightforward integration into existing pipework, making it a vital component for both residential and light commercial installations. By absorbing excess pressure, the MAG 12 helps extend the lifespan of your primary equipment and reduces the risk of leaks or component failure. This is a must-have for any professional installer or homeowner looking to protect their investment in high-performance climate control technology. Built to the exacting standards of German engineering, it provides reliable, long-term performance in demanding UK environments.
Self-install friendly
EasyThis unit is designed for confident DIYers. Guides & video below.
Add smart control
No built-in Wi-Fi — automate this unit with a smart plug & temperature sensor.
- Free UK mainland delivery on in-stock units
- Manufacturer warranty included
- 14-day returns
Technical documents & videos
More from Stiebel Eltron →Official Stiebel Eltron manual
The manufacturer's PDF for this model is being sourced and will be downloadable here.
Full Specifications
Description
The Stiebel Eltron MAG 12 is a high-quality expansion vessel designed to manage pressure fluctuations within your heating or cooling system. Essential for maintaining system integrity, this robust accessory prevents damage caused by thermal expansion, ensuring your Stiebel Eltron heat pump or air conditioning setup operates safely and efficiently. Its compact design allows for straightforward integration into existing pipework, making it a vital component for both residential and light commercial installations. By absorbing excess pressure, the MAG 12 helps extend the lifespan of your primary equipment and reduces the risk of leaks or component failure. This is a must-have for any professional installer or homeowner looking to protect their investment in high-performance climate control technology. Built to the exacting standards of German engineering, it provides reliable, long-term performance in demanding UK environments.
Common questions about the Stiebel Eltron MAG 12 Expansion Vessel
How many BTU is the Stiebel Eltron MAG 12 Expansion Vessel?
The Stiebel Eltron MAG 12 Expansion Vessel is a Accessories — check the specifications for capacity details.
What room size is the Stiebel Eltron MAG 12 Expansion Vessel suitable for?
The Stiebel Eltron MAG 12 Expansion Vessel is recommended for rooms N/A.
Can I install the Stiebel Eltron MAG 12 Expansion Vessel myself?
Yes — the Stiebel Eltron MAG 12 Expansion Vessel is rated as Easy for self-installation. Guides and video tutorials are available on the product page.
Is the Stiebel Eltron MAG 12 Expansion Vessel smart-home compatible?
The Stiebel Eltron MAG 12 Expansion Vessel does not have built-in Wi-Fi control, but you can add smart control using a compatible smart plug.
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Mitsubishi ElectricAnnual energy savings estimate
How much this A-rated unit could save versus a standard C-rated model, based on your usage.
This unit
95 kWh/yr
EER 10
Standard model
119 kWh/yr
EER 8
Est. saving
£6.41
24 kWh/yr less
Estimate based on the unit's energy-rating efficiency factor and cooling capacity (~9,000 BTU assumed). Actual savings vary with room size, climate and usage patterns.
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