Best Hot Water Reservoirs of 2025

Corey Phillips Avatar
Corey Phillips
Last Updated: 19 Jan 2023

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On the hunt for the UK's best hot water reservoirs? We're here to help. We searched 9 hot water reservoirs of different brands including Tesy, Eldom, GRANT, Eccotemp, Caleffi to bring you a trustworthy list of our favorite ones.

Below we compiled a list of the 6 Best Hot Water Reservoirs we believed to meet the demand from various aspects and recommended Tesy Hot Water Reservoir as the best of the best one. You can also have a look at other hot water reservoirs we recommend which are also of great quality and value.

At a Glance: Our Top Picks

TESY Bi-Light 30 Litre Hot Water Cylinder Cover #TOP 1
TESY Bi-Light 30 Litre Hot Water Cylinder
ftb score rating icon 9.8
Eldom Favourite WU08046 80 Litre Electric Hot Water Tank for Universal Mounting, White, 230 V Cover #TOP 2
Eldom Favourite WU08046 80 Litre Electric Hot Water Tank for Universal Mounting, White, 230 V
ftb score rating icon 9.7
Grant Mpss01 12Ltr Expansion Vessel Cover #TOP 3
Grant Mpss01 12Ltr Expansion Vessel
ftb score rating icon 9.5

Top 6 Hot Water Reservoirs

#TOP 1

TESY Bi-Light 30 Litre Hot Water Cylinder

TESY Bi-Light 30 Litre Hot Water Cylinder Cover
TESY Bi-Light 30 Litre Hot Water Cylinder

Features
Patented Piston Effect To Control Refilling
Glass Ceramic Coating,
Wall Mounted
Light Indicator To Show Heating Status
Freeze Protection
#TOP 2

Eldom Favourite WU08046 80 Litre Electric Hot Water Tank for Universal Mounting, White, 230 V

WU08046
19.06 x 18.19 x 32.87 inches
57.32 pounds
Eldom Favourite WU08046 80 Litre Electric Hot Water Tank for Universal Mounting, White, 230 V Cover
Eldom Favourite WU08046 80 Litre Electric Hot Water Tank for Universal Mounting, White, 230 V

Features
Pressure Resistant, Maximum Pressure: 8 Bar.
The Hot Water Tank Can Be Used Both Horizontally And Vertically.
WRAS Approval
Steel Container And Wear-Resistant Zirconium Enamel Coating Of The Water Tank.
Pressure Limiting Valve, The Drain Valve And Check Valve In One, Also Known As Inlet Combination, Included.
Dimensions: 835 X 462 X 484 Mm
#TOP 3

Grant Mpss01 12Ltr Expansion Vessel

GRANT
Grant Mpss01 12Ltr Expansion Vessel Cover
Grant Mpss01 12Ltr Expansion Vessel

Features
Trust A Part Boiler Experts With Over 25 Years Of Heating, Boiler Maintenance And Spare Parts Experience
Same Day Dispatch To The UK Mainland
Family Run Business Priding Itself On High Levels Of Customer Satisfaction
All New Parts Come With A 12 Month Warranty
#TOP 4

Eccotemp ECCL530 Tankless Portable Water Heater, White

ECCL530
12.60 x 7.87 x 22.05 inches
14.55 pounds
Eccotemp ECCL530 Tankless Portable Water Heater, White Cover
Eccotemp ECCL530 Tankless Portable Water Heater, White

Features
Lightweight, Easy To Carry, And Compact, Makes Using It For Camping, Hunting, In Your Tiny Home, RV's, Poolside, Washing Pets, Equestrian, Cleaning Vehicles, Greenhouses Or Anywhere Else That You Need Instant Reliable Endless Hot Water Perfect For Hot Water Anywhere You Need It.
Being Designed And Developed In Summerville SC USA, The Eccotemp CEL5 Is The Only Legal CE GAR Certified Portable Tankless Water Heater On The Market That Can Legally Be Sold In Europe!
Runs On A Standard 20 Lb. Liquid Propane Tank And Is Equipped With An Electronic Ignition. Powered By 2 “D” Cell Batteries, Making It Ideal For On-The-Go. Make The L5 Even More Convenient And Pair It With The EccoFlo 12v Water Pump, Allowing You To Have Hot Water In The Most Remote Locations!
Real, Appointment Based Dedicated Support Available M-F, 8am-8pm EST. Eccotemp Also Offers Live Chat And 24/7 Self Help Desk To Keep You In HOT WATER. With Educated Technical Support, Manuals, Troubleshooting All Available At Your Fingertip You'll Have Peace Of Mind When Purchasing An Eccotemp Product.
Rated At 6 Liters Per Minute (LPM), The CEL5 Can Produce Hot Water With Water Pressure As Low As 20PSI And Achieve Temperatures Ranging From 10-60 Degrees Celsius. Simply Adjust The Water And Gas Flow To Achieve Your Desired Temperature.
#TOP 5

Caleffi SiCalCenter 528821 Security Centre for Closed WW Seperators 3/4 Inch 10 Bar AD 12 L Max. 380 L Multi-Coloured

K12845-003
15.75 x 15.75 x 15.75 inches
Caleffi SiCalCenter 528821 Security Centre for Closed WW Seperators 3/4 Inch 10 Bar AD 12 L Max. 380 L Multi-Coloured Cover
Caleffi SiCalCenter 528821 Security Centre for Closed WW Seperators 3/4 Inch 10 Bar AD 12 L Max. 380 L Multi-Coloured

Features
With Expansion Vessel According To DIN 4807 For Hot Water Heating Systems According To DIN 1988.
SiCalCenter - Safety Centre For Closed Water Heaters In Accordance With DIN EN 1488
Max. Operating Temperature: 70°C.
Max. Operating Pressure: 10 Bar.
For Horizontal And Vertical Installation.
#TOP 6

Bosch Thermotechnik TR3500 T 30 B TR3500T Wall Storage, 230 V, White-Grey

TR3500 T 30 B
20.08 x 20.16 x 19.69 inches
44.09 pounds
Bosch Thermotechnik TR3500 T 30 B TR3500T Wall Storage, 230 V, White-Grey Cover
Bosch Thermotechnik TR3500 T 30 B TR3500T Wall Storage, 230 V, White-Grey

Features
Economical And Efficient: Low Standby Consumption For An Effective, Decentralised Hot Water Supply.
Electrically Powered Wall Storage For Comfortable Supply Of Warm Water In The Kitchen Or Bathroom.
User And Comfortable: Clear User Interface With Display Of The Available Water Quantity.
Safe And Reliable: With Frost Protection Setting To Prevent The Water From Freezing - Safety Tested By The VDE Testing Institute.
Product Data: 20 Kg I 490 X 500 X 512 Mm I 230 Volt I Installation Method: Hanging I Colour: White/grey
Predecessor: DG30011D2, DG30011D2.
Buying Guide Image

Frequently Asked Questions (FAQs)

1. How long do geothermal reservoirs last?

Geothermal energy infrastructure has longevity Geothermal heating and cooling systems have a very long lifespan in comparison to many other green energy solutions. The US Department of Energy estimates a 20 year lifespan for heat pumps, and up to 50 years for the underground infrastructure.

2. What heats geothermal reservoir?

1 Geothermal Heating Systems. The geothermal reservoir is an aquifer with hot water or steam. A geothermal heating system is illustrated in Figure 16.1. A production well is used to withdraw hot water from the geothermal reservoir, and an injection well is used to recycle the water.

3. How hot can geothermal water get?

Credit: Patrick Laney, NREL 13104 Direct use geothermal systems use groundwater that is heated by natural geological processes below the Earth's surface. This water can be as hot as 200°F or more. Bodies of hot groundwater can be found in many areas with volcanic or tectonic activity.

4. What are the four types of geothermal reservoirs?

Today's Geothermal Energy There are four main kinds of geothermal resources: hydrothermal, geopressured, hot dry rock, and magma.

Editor's Notes

During our hot water reservoir research, we found 9 hot water reservoir products and shortlisted 6 quality products. We collected and analyzed 4,307 customer reviews through our big data system to write the hot water reservoirs list. We found that most customers choose hot water reservoirs with an average price of £198.38.

The hot water reservoirs are available for purchase. We have researched hundreds of brands and picked the top brands of hot water reservoirs, including Tesy, Eldom, GRANT, Eccotemp, Caleffi. The seller of top 1 product has received honest feedback from 69 consumers with an average rating of 4.6.

Written by
Corey Phillips Avatar

Corey Philips is an electrician and lighting expert. He graduated from the University of Birmingham in 2012 with a Bachelor's degree in electrical and electronics engineering. Corey is a specialist contractor in lights. He sells and installs and recommends lights and lamp sheds, and other lights accessories. Aside from that, Corey is vast in installing and maintaining electrical appliances like air conditioners, water heaters, and the likes.