Cloakroom and workshop
You need one warm spout on cold mains, for a short wash in a cloakroom, workshop or shed. A 3 kW instantaneous handwash fits that job. It does not fill a washing-up bowl.
Point-of-use water heater comparison 2026
The best point-of-use water heaters, compared.
Top pick: COMFEE' 10 L undersink Best value: Triton T30i handwash – Lowest price among listings that still score at least 80: about £55.99, with 4.4 from 842 reviews. Reviewers call it lukewarm for a kitchen, so it is a hand basin only. Updated 17.10.2026.
A point-of-use water heater makes hot water at one outlet, or at two a short pipe apart, instead of feeding a whole home from a cylinder. In the UK that is a small store, usually 5–15 litres, or an instantaneous heater from about 3 kW for a hand basin up to about 9–12 kW for a kitchen sink or a modest shower. Typical jobs are a cloakroom, a garden room, a kitchenette or an all-electric flat. Quality shows up as an honest kilowatt and voltage figure, a tap that matches the vessel, and a circuit that can carry the current. At 230 V, 3 kW is about 13 A, 6 kW about 26 A, and 12 kW about 52 A. A 6 kW or 10–12 kW heater is not a 13 A plug. Litres, kilowatts and supply are in the [point-of-use water heater buying guide](/hub/hot-water/point-of-use-water-heater/sub/point-of-use-water-heater-buying-guide). A 100 litre wall heater is a dwelling store, and one such listing was left out of this set.
A point-of-use water heater makes hot water at one outlet, or at two a short pipe apart, instead of feeding a whole home from a cylinder.
38 products checked · 61 hrs invested · +18,600 readers
11 of 11: Best point-of-use water heaters compared
Swipe for more
1-2 of 11Best overall
8.9/10
9.0/10
9.0/10
9.0/10
8.4/10
6.4/10
5.6/10
1.0/10
1.0/10
1.0/10
1.0/10
∼ £80
∼ £56
∼ £413
∼ £133
∼ £95
∼ £45
∼ £45
∼ £58
∼ £54
∼ £50
∼ £45
4.7(21)
4.4(842)
4.4(116)
4.4(30)
4.1(63)
3.1(5)
2.7(8)
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Personal buying guide
Which point-of-use water heater fits?
Question 1 of 2
What are you heating?
The best point-of-use water heaters in detail
Our view
The COMFEE' stores 10 litres under the sink and draws 2 kW at 220 V. Of 21 amazon.co.uk ratings the average is 4.7, the highest in this set, and UK reviewers describe quick heat for washing-up in a holiday home, a garden-room kitchen or a small shower for two. One buyer measured the stated 2 kW draw, and another removed a shelf to clear the 30 cm depth. A professionally fitted unit failed and the return was slow, and a separate review called the UK paperwork thin. The case is 32.4 cm wide, 32.4 cm high and 30 cm deep, at 7.4 kg, with a stated maximum of 75°C. Energy class A still depends on the declared load profile. A 10 litre, 2 kW store will not keep a shower going, even where the listing text mentions showering.
Pros
- 10 litre undersink store at £79.99 with energy class A
- 4.7 from 21 UK ratings, the highest average in this set
- Buyers report a fit under a sink after measuring the 30 cm depth
- Stated maximum of 75°C, with dry-burn protection listed
Cons
- One professionally fitted unit failed and the refund was slow
- One reviewer called the UK paperwork thin
- The 30 cm depth can mean taking out a shelf
- 21 ratings is a much smaller file than the Triton's
Best for: A single sink that needs about a bowl of hot water and a cupboard around 32 cm square and 30 cm deep.
Less suitable: A long shower, or a buyer who wants a review file of several hundred ratings.
Specifications
- Model
- COMFEE' 10 L undersink
- Brand
- COMFEE'
- Price
- ∼£80
- Customer rating
- 4.7/5(21)
- Type
- Undersink store
- Power
- 2 kW
- Capacity
- 10 litres
- Voltage
- 220 V
- Supply
- Corded
- Mount
- Undersink
- Max temperature
- 75°C
- Energy class
- A
Common questions
Is this an undersink storage heater?
Yes. The listing is a 10 litre undersink storage water heater.
What electrical load does it state?
2,000 W at 220 V AC.
How large is the case?
32.4 cm wide, 32.4 cm high and 30 cm deep, at 7.4 kg.
Our view
The Triton T30i, model SPT303I, is a 3 kW instantaneous handwash for a basin on cold mains, listed at £55.99. It averages 4.4 from 842 amazon.co.uk reviews, the largest file in this comparison, and several buyers fit it in a cloakroom, workshop or shed as a replacement for an older T30i. The same reviews say the water stays lukewarm if you expected kitchen-hot water, and that flow and pressure drop. Comments on the build mention two wall fixings and a plastic water-inlet thread. The listing states 8 litres per minute; at that flow a 3 kW element adds only a few degrees, so the figure is not a hot-water promise. One installer reported a thermostat failure after about three days. The unit weighs about 1 kg and the listing does not describe a shower.
Pros
- 4.4 from 842 reviews, the largest file in this set
- £55.99 for a named 3 kW handwash
- UK reviewers use it where only cold mains is available
- Several treat it as a direct replacement for an older T30i
Cons
- Lukewarm if you wanted washing-up heat
- Flow and pressure drop in the reviews
- Plastic inlet thread, and a spout arm reviewers find awkward
- The stated 8 L/min is not hot water at that flow
Best for: A cloakroom, workshop or shed basin on cold mains, where a short warm wash is the job.
Less suitable: A kitchen bowl, a shower, or a long 3 kW duty left on a 13 A plug for hours.
Specifications
- Model
- Triton T30i handwash
- Brand
- Triton Showers
- Price
- ∼£56
- Customer rating
- 4.4/5(842)
- Type
- Instant handwash
- Power
- 3 kW
- Capacity
- None
- Supply
- Corded
- Mount
- At the basin
- Temperature control
- Single control
- Energy class
- A
Common questions
Is this for a shower?
The listing calls it a handwash water heater for use where only a cold mains supply is available. It does not describe a shower.
What power does it state?
3 kW, energy class A, with a stated flow of 8 litres per minute.
What pressure does the listing allow?
Maximum pressure is stated as 10 bar.
Our view
The Stiebel Eltron DCE-X 10/12 Premium is an instantaneous oversink heater listed at up to 12 kW, 5 litres per minute and 55°C, on 220/240 V. Across 116 amazon.co.uk reviews the average is 4.4, and UK buyers praise a steady set temperature at a kitchen sink or basin once a dedicated cable is in. Reviewers describe their own supplies as 10 mm² or 16 mm² cable and a 50 A or 60 A breaker; those are install reports, not a design for your consumer unit. Shower comments split between a usable shower and a flow that collapses. Running cost is compared unfavourably with a standard electric shower, even in the ECO mode. The case is about 217 mm wide, 372 mm high and 109 mm deep, at 2.5 kg, and it cannot go on a 13 A socket. The shelf price on 15 October 2026 was £412.86, before that circuit.
Pros
- Electronically controlled 10/12 kW output, stated 5 L/min and 55°C
- 4.4 from 116 reviews, many of them in the UK
- Compact oversink case at 2.5 kg
- Display, two memory keys and an ECO mode on the listing
Cons
- Needs its own high-current circuit, not a 13 A socket
- Shower reviews disagree
- £412.86 before the cable and the breaker
- One report of noise and a stop from the first day
Best for: An all-electric sink, or a modest shower, only after an electrician has confirmed the consumer unit.
Less suitable: A plug-in cloakroom, a bath, or a buyer who wanted a guaranteed shower.
Specifications
- Model
- Stiebel Eltron DCE-X 10/12 Premium
- Brand
- Stiebel Eltron
- Price
- ∼£413
- Customer rating
- 4.4/5(116)
- Type
- Instant oversink
- Power
- 10/12 kW
- Capacity
- None
- Voltage
- 220/240 V
- Supply
- Own circuit
- Mount
- Oversink
- Max temperature
- 55°C
- Temperature control
- Display, ECO
- Energy class
- A
Common questions
Can it be plugged into a normal socket?
The listing says an electric cable prepared for the power connection. Reviewers say it cannot be plugged into a mains socket and describe a dedicated high-current circuit.
Does the listing say it suits a shower?
The title says suitable for showers, and also for kitchens or utility sinks. Review texts both support and reject shower use.
What output does the listing print?
The model name is 10/12 kW. Wattage and heat output are printed as 12 kW, flow as 5 litres per minute, maximum temperature 55°C.
Our view
The Ariston Andris R stores 15 litres under the sink and heats that water with a 3 kW element at 230 V. Across 30 amazon.co.uk ratings the average is 4.4, and the written UK reviews mostly describe a kitchen, annexe or staff-room sink with enough hot water for washing up. The box includes a pressure relief valve, dielectric junctions and a wall bracket, while the same listing says installation kits are bought separately. One UK reviewer found the inlet and outlet rusty after about three months, with black particles in the water, so the short file is not a clean record. The case is 34.6 cm wide and 38.5 cm high at 7.5 kg, and the depth is not stated. Energy class B describes this load profile rather than a smaller bill, and the listing does not sell the tank as a shower.
Pros
- 15 litre undersink store at 3 kW and 230 V
- Relief valve, dielectric junctions and wall bracket included
- UK reviews describe enough hot water for a sink
- Three-year warranty stated on the listing
Cons
- One UK review reports rust and black particles after three months
- Depth is not stated, and installation kits are extra
- Only eight written reviews sit under a count of 30
- £133.19 is the dearer store in this set
Best for: A kitchenette, annexe or staff sink that needs a bowl of stored hot water on a 3 kW supply.
Less suitable: A handwash-only cloakroom, a shower, or a cupboard that cannot take a tank 38.5 cm high.
Specifications
- Model
- Ariston Andris R 15 L undersink
- Brand
- Ariston
- Price
- ∼£133
- Customer rating
- 4.4/5(30)
- Type
- Undersink store
- Power
- 3 kW
- Capacity
- 15 litres
- Voltage
- 230 V
- Supply
- Corded
- Mount
- Undersink
- Temperature control
- Economy dial
- Energy class
- B
Common questions
Can this heater go under a sink?
The listing titles it as a 15 litre undersink electric water heater and gives a wall mount.
What power does the listing state?
3 kW at 230 V, with energy class B.
What comes in the box?
A pressure relief valve, dielectric junctions, a wall bracket, an installation manual and a warranty certificate. The same listing says installation kits are to be purchased separately.
Our view
The FVSTR title offers a small undersink store at 2 kW, 2.5 gallons and a UK plug, priced at £94.95. The specification block on the same amazon.co.uk page says 120 V, 1,500 W and 2.16 gallons, and a bullet also mentions 240 V. The average is 4.1 from 63 ratings, but almost every written review in the sample is from the United States, Canada or Australia, with one from the UK. Those buyers like the size for one tap and report weak pressure on the hot side, plus a relief valve that opens when there is water hammer. A Canadian electrician refused a unit for lack of a local approval mark, and another buyer reported three units that did not work. Until the nameplate on the delivered heater reads 230 V, this is not a settled UK mains product.
Pros
- Small listed case, about 20 cm wide by 27 cm high
- 4.1 from 63 ratings for single-tap use, mostly outside the UK
- Pressure relief valve included
- Adjustable thermostat stated on the listing
Cons
- Specification says 120 V and 1,500 W against a UK-plug, 2 kW title
- Written reviews are almost all from outside the UK
- Weak hot-side pressure and relief-valve discharge in the sample
- A leak, and a report of three units that did not work
Best for: Only a buyer who checks the delivered nameplate for 230 V before connecting it.
Less suitable: Anyone who needs a settled UK mains heater, or a kitchen bowl from a confirmed 2 kW element.
Specifications
- Model
- FVSTR small undersink tank
- Brand
- FVSTR
- Price
- ∼£95
- Customer rating
- 4.1/5(63)
- Type
- Undersink store
- Power
- 1.5 kW spec
- Capacity
- 2.16 gal
- Voltage
- 120 V
- Supply
- UK plug title
- Mount
- Undersink
- Temperature control
- Thermostat
- Energy class
- A
Common questions
Does the listing agree on voltage?
No. The title says a UK plug. The specification says 120 V and 1,500 W. A bullet also mentions a 240 V connection.
What capacity is stated?
The title says 2.5 gallon. The specification says 2.16 gallons.
Is a relief valve included?
Yes. The included-components line lists a pressure relief valve, the body and a manual.
Our view
The Axelrivet is listed as a 3,000 W instantaneous heater with a UK plug, IPX4 and a 30–55°C display, at £44.99. Five UK reviews average 3.1. Two are short and positive once the unit is under a sink. The others say it powered for about 10 seconds and then died, that it heats only when the flow is very low, and that one buyer measured over 4,200 W against the 3,000 W claim. The page prints both flow and capacity as 2.9 and does not state a voltage. Five reviews cannot turn the two kind comments into a pattern, and a 3 kW element at a normal sink flow adds little heat.
Pros
- Shelf price of £44.99
- UK plug and IPX4 stated on the listing
- Two of five UK reviews were positive once it was under a sink
Cons
- 3.1 from only five reviews
- One unit died after about 10 seconds
- Heat only at a very low flow in another review
- One buyer measured over 4,200 W against a 3,000 W claim
Best for: Only a cautious trial on a small basin, if you can return it.
Less suitable: A kitchen sink, a shower, or anyone who needs a stable 3 kW draw.
Specifications
- Model
- Axelrivet 3,000 W undersink
- Brand
- Axelrivet
- Price
- ∼£45
- Customer rating
- 3.1/5(5)
- Type
- Instant
- Power
- 3 kW
- Capacity
- None
- Supply
- UK plug
- Mount
- Above or under
- Max temperature
- 55°C
- Temperature control
- Touch display
- Ingress protection
- IPX4
Common questions
Does it come with a UK plug?
The title and the bullets say a standard UK plug with a built-in fuse.
What flow does the listing claim?
2.9 litres per minute, with a 30–55°C touch display. Capacity is also printed as 2.9 litres.
Is it for under a sink?
The title says under sink. A bullet says it can go above or under a sink.
Our view
The Builrand is a 3,000 W, 220 V undersink instantaneous heater with IPX4 and a stated maximum of 50°C, listed at £44.99. Eight amazon.co.uk ratings average 2.7, and five written UK reviews sit in the file. Four of those five say it does not heat or only takes the chill off, and one describes a leak from the bottom and a return. The remaining review accepts that mild output because young children only needed the chill taken off. The listing says a lower flow runs hotter, which is what a 3 kW element does, not a 50°C result at a normal tap. It does not claim a UK plug, and the energy class is printed as a lowercase a.
Pros
- Shelf price of £44.99
- 220 V and IPX4 stated
- One reviewer found the mild output acceptable for children's handwashing
Cons
- 2.7 from eight ratings
- Four of five written reviews report almost no useful heat
- A leak from the bottom in the sample
- No UK plug claim
Best for: Not a working-heater pick on the written reviews in this set.
Less suitable: Washing up, a shower, or a buyer who needs the stated 50°C at a normal flow.
Specifications
- Model
- Builrand 3,000 W undersink
- Brand
- Builrand
- Price
- ∼£45
- Customer rating
- 2.7/5(8)
- Type
- Instant
- Power
- 3 kW
- Capacity
- None
- Voltage
- 220 V
- Supply
- Corded
- Mount
- Undersink
- Max temperature
- 50°C
- Temperature control
- LED display
- Ingress protection
- IPX4
- Energy class
- A
Common questions
Is it sold for under a sink?
Yes. The title describes a 3,000 W under-sink instantaneous heater for a kitchen or bathroom.
What temperature does the listing state?
Maximum temperature 50°C. Bullets give a band of about 20–50°C and say a lower flow runs hotter.
Does the listing claim a UK plug?
No. Power source is corded electric at 220 V. A bullet recommends professional installation for UK plumbing.
Our view
The Mulcort listing states 3,000 W, a UK plug, a G1/2 connection, IPX4 and control from 28°C to 55°C, at £57.99. The amazon.co.uk dump has no star rating and no review text, so nothing here shows that it heats a basin. A bullet lists a shower head, hose and wall bracket, while the included-components line lists only a user manual, and the remote needs two AAA batteries that are not in the box. At 3 kW that shower head does not make a shower. The case is about 20 cm by 11.5 cm by 7.7 cm and 1.67 kg, in ABS. The listing itself says the socket and circuit must suit a 3,000 W appliance.
Pros
- States a UK plug, a G1/2 connection and IPX4
- Compact case, about 7.7 cm deep
- Temperature band printed as 28–55°C
Cons
- No ratings and no written reviews
- Shower kit in the bullets, user manual only on the components line
- 3 kW is a handwash load, not a shower
- Remote batteries are not included
Best for: Not a pick from this file until UK reviews exist.
Less suitable: A shower, a kitchen bowl, or a buyer who needs customer evidence.
Specifications
- Model
- Mulcort 3,000 W with remote
- Brand
- Mulcort
- Price
- ∼£58
- Type
- Instant
- Power
- 3 kW
- Capacity
- None
- Supply
- UK plug
- Mount
- Undersink
- Max temperature
- 55°C
- Temperature control
- Remote
- Ingress protection
- IPX4
Common questions
Does it state a UK plug?
Yes. The bullets say a UK plug and a G1/2 water connection, and that the socket and circuit must suit a 3,000 W appliance.
What temperature range is printed?
28°C to 55°C. The listing says outlet temperature depends on inlet temperature and flow.
Is a shower head included?
A bullet lists a shower head, hose and wall bracket. The included-components line lists only a user manual.
Our view
The Normodic undersink listing states 6,000 W at 220 V, a 30–52°C display and a 2.5 mm² copper wire rather than a UK plug, at £53.99. The amazon.co.uk file has no review score and no review text. At about 6 kW the current is roughly 26 A, so this is a dedicated-circuit appliance, and a shower head in the marketing text is not evidence of a shower. The included-components line names one heater, while the bullets also mention a hose, a shower head and brackets. The case is listed at 22 cm wide by 34 cm high and 1.9 kg. Leak detection and the nine protections in the title remain catalogue claims until a buyer reports them.
Pros
- 6 kW is in the range a kitchen instant heater needs on paper
- States 220 V and a 2.5 mm² cable rather than a 13 A plug
- Listed case about 22 cm wide by 34 cm high
Cons
- No ratings and no reviews
- About 6 kW is not a 13 A socket
- Included parts conflict between the heater-only line and the shower kit
- Ingress protection is not stated
Best for: Not a buy until an electrician has specified the circuit and UK reviews exist.
Less suitable: A plug-in basin, or anyone choosing from star ratings.
Specifications
- Model
- Normodic 6,000 W undersink
- Brand
- Normodic
- Price
- ∼£54
- Type
- Instant undersink
- Power
- 6 kW
- Capacity
- None
- Voltage
- 220 V
- Supply
- 2.5 mm² cable
- Mount
- Undersink
- Max temperature
- 52°C
- Temperature control
- LED display
Common questions
What power supply does the listing describe?
6,000 W at 220 V, with a 2.5 mm² copper wire mentioned. A UK plug is not stated.
Is it described as a point-of-use heater?
Yes. The title says an under-sink tankless point-of-use heater for a kitchen sink and hand wash.
Are there customer reviews in the saved listing?
No review score and no review text are present.
Our view
This second Normodic states 6,000 W at 220 V and 50 Hz, IPX4, a 30–55°C control with memory, and a 25 A or larger residual current device, at £49.99. There is no customer-review line in the dump. Depth is 7.9 cm and weight is 1.44 kg; width and height are not given. The bullets claim a kitchen, handwashing and a shower. A 6 kW element can raise water by about 29°C at 3 litres a minute, which is a calculation from the power figure, not a test of this unit, and it still needs its own circuit. The included-components line is absent. The low price is not evidence that the heater works.
Pros
- States 6,000 W, 220 V, IPX4 and a 25 A residual current device
- Slim listed depth of 7.9 cm
- Temperature band of 30–55°C with memory claimed
Cons
- No reviews
- Width and height are missing from the saved listing
- 6 kW cannot use a 13 A plug
- The shower claim is a bullet, not a reported result
Best for: Hold it until there is a UK review file and a confirmed circuit.
Less suitable: A cloakroom on a fused spur, or a shower bought from the bullet list.
Specifications
- Model
- Normodic 6,000 W tankless
- Brand
- Normodic
- Price
- ∼£50
- Type
- Instant
- Power
- 6 kW
- Capacity
- None
- Voltage
- 220 V
- Supply
- 25 A RCD
- Mount
- Undersink
- Max temperature
- 55°C
- Temperature control
- Stepless
- Ingress protection
- IPX4
Common questions
What circuit does the listing mention?
It says the unit is compatible with a 25 A or above residual current device. Power is stated as 6,000 W at 220 V.
Where does it say it can be fitted?
The bullets describe an under-sink heater for a kitchen, handwashing and a shower.
Are width and height given?
No. Depth is 7.9 cm and weight is 1.44 kg. Width and height are not in the saved listing.
Our view
The laloohome title says 6,000 W, while the technical details say 5,500 W at 220 V, and the two size lines also disagree. Technical details give 26 × 23 × 8 cm; a bullet gives about 21 × 15 × 5.1 cm. The amazon.co.uk dump has no reviews, and the listing was first available on 19 August 2026. It asks for a dedicated circuit, cable of 2.5 or 4 mm² and a fuse of at least 40 A, which is the seller's figure rather than a design for your consumer unit. IPX4 and a 30–55°C display are printed, and the box list includes the heater, mounting hardware and a manual. At £44.99 it is the cheapest high-wattage claim here, with no customer evidence behind it.
Pros
- States a dedicated circuit rather than a UK plug
- IPX4 and a 30–55°C display are claimed
- Mounting hardware and a manual are listed in the box
Cons
- Title says 6,000 W and the technical details say 5,500 W
- Two conflicting dimension sets
- No reviews, on a listing first available on 19 August 2026
- A fuse of at least 40 A is a circuit project, not a socket
Best for: Not a buy from this file.
Less suitable: Any outlet until the wattage, the size and a UK review agree.
Specifications
- Model
- laloohome tankless heater
- Brand
- laloohome
- Price
- ∼£45
- Type
- Instant
- Power
- 5.5 kW spec
- Capacity
- None
- Voltage
- 220 V
- Supply
- 40 A fuse
- Mount
- Over or under
- Max temperature
- 55°C
- Temperature control
- Touch control
- Ingress protection
- IPX4
Common questions
Is the wattage consistent?
No. The title says 6,000 W. The technical details say 5,500 watts. A bullet again says 6,000 W.
What supply does the listing require?
220 V, a dedicated independent circuit, cable of 2.5 or 4 mm², and a fuse of at least 40 A.
Which dimensions are printed?
Technical details say 26 x 23 x 8 cm and 1.25 kg. A bullet says about 21 x 15 x 5.1 cm.
How we compared
Scores compare the eleven amazon.co.uk listings kept for this category. The dump date is 15 October 2026. They are not a laboratory test, and they do not name the best point-of-use heater in the UK. Each score weighs the four points below. A listing with no customer-review line scores 0.
1
Customer evidence
40%Stars and the review count on that ASIN, the heaviest part of the score. Written themes come from the review sample. A listing with no customer-review line scores 0.
2
A coherent UK job
25%Litres or kilowatts, voltage, and a tap or cable story that matches one outlet. A title that fights the specification loses points.
3
Price against that job
20%A low shelf price does not repair a dead element or an empty review file. The best value is the lowest price among listings that still score at least 80.
4
Recurring faults
15%Voltage clashes, a 3 kW unit sold as a shower, a failed fitted unit, and a tiny or hostile review sample are already reflected in the score.
Independent review
Last updated: 17.10.2026
8 sources checked
Point-of-use water heater buying guide
Choose the outlet first, then stored or instant heat, then the tap and the circuit. A hand basin, a kitchen bowl and a modest shower are different loads. Prices below are the amazon.co.uk shelves on 15 October 2026, and fitting is not included. Energy class A or B describes a load profile. It is not a promise that the bill halves.
What is a point-of-use water heater?
A point-of-use water heater makes hot water at one outlet, or at two outlets a short pipe apart, instead of feeding a whole home from a cylinder. In the UK that means a small store, usually 5–15 litres under or over a sink, or an instantaneous heater from about 3 kW for a hand basin up to about 9–12 kW for a kitchen sink or a modest shower. A bath is outside this category. A 100 litre wall heater is a dwelling store, and one such listing was left out of this set.
Best for
- A cloakroom, workshop or shed basin on cold mains
- A kitchenette that needs about a bowl of stored hot water
- An all-electric sink after an electrician has confirmed the circuit
Not ideal for
- A shower bought as a 3 kW plug-in heater
- A bath, or a whole flat run from one 15 litre tank
- A buyer who treats energy class A as a cut in the bill
Mistakes to avoid
- 1
Buying 3 kW instant heat for washing up
A 3 kW element adds about 21°C at 2 litres a minute and about 5°C at 8 litres a minute. That is a calculation, not a test. Reviewers call the Triton T30i lukewarm when they wanted a kitchen bowl. A washing-up bowl suits about 10 litres stored.
- 2
A standard mixer on a vented tank
Open-outlet storage must use the maker’s tap and will drip while it heats. A normal mixer on that tank is a mistake. Do not cap a drip that only happens during heat-up.
- 3
Trusting a UK-plug claim against the specification
The FVSTR title says a UK plug and 2 kW. The specification says 120 V and 1,500 W. A 6 kW listing is about 26 A and is not a 13 A plug. Check the nameplate, and the cable, before you connect it.
What to weigh up
Outlet, stored or instant
HighThe outlet decides the heater. One hand basin is a 3 kW instant handwash or about 5 litres stored. A kitchen sink wants about 10–15 litres stored, or an instantaneous heater nearer 6–12 kW. A shower is not a 3 kW job, and a bath is outside this category. Storage gives a proper flow until the tank is empty, then a wait. Instant heat never runs out in that sense, but temperature rise is capped by power and flow.
Tap type, supply and temperature
HighOpen-outlet storage uses one vented tap and drips while it heats. Unvented storage of 15 litres or less can feed a normal tap if the safety kit is fitted. A normal mixer on a vented tank is a mistake. At 230 V, 3 kW is about 13 A, 6 kW about 26 A, and 12 kW about 52 A. A new circuit is notifiable in England, and so is a bathroom-zone alteration. A 6 kW or 10–12 kW heater is not a 13 A plug. A long 3 kW immersion is a poor match for a BS 1363 plug.
Which option suits you?
Three typical situations, each with a recommendation from this comparison.
Kitchenette
You need a bowl’s worth of hot water and usually a cupboard. About 10 litres stored at 2 kW matches a single sink. It will not keep a shower going.
All-electric flat
You want a 10–12 kW instantaneous heater at a sink, or a modest shower, and an electrician has confirmed the consumer unit. This is not a plug-in job.
Common questions about point-of-use water heaters
Which point-of-use water heater is the top pick in this comparison?
The top pick on this page is the COMFEE' 10 litre undersink store, about £79.99, rated 4.7 from 21 amazon.co.uk reviews. It draws 2 kW at 220 V and is meant for about a bowl of hot water at one sink. It is not a shower, and it is not a laboratory winner. One professionally fitted unit failed, and 21 ratings is a much smaller file than the Triton T30i. It leads because that average is the highest on a clear 10 litre listing.
How much does a point-of-use water heater cost on amazon.co.uk?
On these eleven shelves, checked on 15 October 2026, prices run from about £44.99 to £412.86. Entry instant listings are about £44.99 to £57.99. The Triton T30i is about £55.99, the COMFEE' 10 litre store about £79.99, the FVSTR about £94.95, and the Ariston 15 litre store about £133.19. The Stiebel Eltron DCE-X 10/12 is about £412.86 before any new circuit. Fitting is not in those prices.
What should you check before you buy a point-of-use water heater?
Start with the outlet. A hand basin is a 3 kW instant handwash or about 5 litres stored. A kitchen sink wants about 10–15 litres stored, or an instantaneous heater nearer 6–12 kW. Then check stored or instant heat, and whether the tank is open-outlet or unvented. A vented tank needs the maker’s tap and will drip while it heats. At 230 V, 3 kW is about 13 A. 6 kW is about 26 A, and 12 kW about 52 A. Those last two are not 13 A plugs.
Is a 3 kW heater enough for a kitchen sink or a shower?
No, if you want a proper hot flow. A 3 kW element gives about 21°C at 2 litres a minute and about 5°C at 8 litres a minute. That is a calculation, not a test. The Triton listing states 8 litres a minute, and reviewers call the T30i lukewarm when they wanted washing-up heat. A kitchen bowl suits about 10 litres stored. A shower is not a 3 kW job, and a bath is outside this category.
What is the difference between a vented tank and an unvented tank?
Open-outlet, or vented, storage uses one special tap and drips while it heats. Do not fit a normal mixer, and do not cap that heat-up drip. Unvented storage of 15 litres or less can feed a normal tap if the safety kit is fitted, because the tank sits on mains pressure. England and Wales water fittings need a servicing valve. An unvented store above 15 litres needs temperature relief. Call a professional for that safety kit and its discharge.
Does under 15 litres mean Building Regulations do not apply?
No. In England, Approved Document G says 15 litres or less, with suitable safety devices, generally meets G3(3). Notification usually falls away if the electrics are also non-notifiable. The safety duty remains. A new circuit, or work in a bathroom zone, is notifiable under Part P. Scotland and Northern Ireland use their own building and water rules. A 100 litre wall heater is a dwelling store, which sits with a hot water cylinder, not on this page.
When should you call an electrician?
Call a professional for any new circuit or bathroom-zone wiring, for an unvented safety kit and its discharge, and for a 9–12 kW heater such as the Stiebel Eltron DCE-X. The Stiebel listing prepares a cable, and reviewers describe a dedicated high-current supply, not a 13 A socket. Also call if a valve is discharging outside heat-up, or if a plug smells hot. A UK plug printed on a title does not make a 6 kW heater safe to plug in.
Why do some cheap listings score zero?
Four listings have no customer-review line on the amazon.co.uk dump of 15 October 2026, so the score stays at 0. They are the Mulcort, both Normodic 6 kW heaters, and the laloohome. A low shelf price does not repair an empty review file. The laloohome title says 6,000 W and the technical details say 5,500 W. The FVSTR title says a UK plug and 2 kW, while the specification says 120 V and 1,500 W. Check the nameplate before you connect it.
Our verdict
The top pick is Triton T30i handwash, with the highest score in this comparison (9 out of 10, from 842 amazon.co.uk reviews). The best value is the Triton T30i at about £55.99, with 4.4 from 842 reviews, and only for a hand basin. The Stiebel Eltron DCE-X 10/12 stays at the same score band as the Triton because it needs its own high-current circuit and the shower reviews disagree.
Best value
View offer
Triton T30i handwash
Lowest price among listings that still score at least 80: about £55.99, with 4.4 from 842 reviews. Reviewers call it lukewarm for a kitchen, so it is a hand basin only.
Editorial
Editor
DIY & toolsWater heatersElectrical fittings
Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Updated: 17.10.2026
8 sources checked
Guides to point-of-use water heaters
Guides on what to look for, how to use a product, and common mistakes.
Point-of-use water heater buying guideLitres, kilowatts, tap type and supply, without an ASIN ranking.Best point-of-use water heaterWho the Triton, the small stores and the Stiebel are for, and who should skip them.How to install a point-of-use water heaterFill, the vented tap, isolation, and the point where you stop and call a professional.Undersink or instantA stored tank against on-demand heat, as one technology choice.Kitchen or basinA hand basin against a kitchen sink, and why a shower is a different job.
Related comparisons
Sources
Public UK sources used for this comparison. Listing prices, stars, and review counts are from amazon.co.uk extracts dated 15 October 2026.
- Approved Document G, with 2024 amendments (retrieved 15 October 2026)
- Approved Document P, 2013 (retrieved 15 October 2026)
- Water Supply (Water Fittings) Regulations 1999 (retrieved 15 October 2026)
- HSE HSG274 Part 2 (retrieved 15 October 2026)
- IET Wiring Matters, September 2025 — 3 kW and BS 1363 (retrieved 15 October 2026)
- Retained regulation 812/2013, Annex II (retrieved 15 October 2026)
- Ariston Andris Lux, UK (retrieved 15 October 2026)
- Stiebel Eltron — instantaneous versus stored water heaters (retrieved 15 October 2026)
This page contains affiliate links to amazon.co.uk. If you buy through them, we may earn a commission at no extra cost to you. Prices, stars, and review counts are the UK listing lines. We did not run a lab test.