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Gas water heater buying guide

Updated: 17.10.2026

A gas water heater buying guide has to start with the room. Amazon.co.uk mixes a portable cylinder burner with a flued heater for a mains-gas wall, and the longer review counts sit on the camping showers. Those stars help if you are washing a horse. They send you the wrong way if you are choosing a bathroom. This page takes place, then fuel, then flow at a real temperature rise, then pressure, then the 15 October 2026 prices in this set. Every kept listing is on the [gas water heater comparison](/hub/hot-water/gas-water-heater). There is no lab test. A qualifying purchase through the links can earn a commission at no extra cost to you.

A gas water heater buying guide has to start with the room. Amazon.co.uk mixes a portable cylinder burner with a flued heater for a mains-gas wall, and the longer review counts sit on the camping showers.

Our top picks

CAMPLUX Camplux BW264BC 10 L gas water heater with rain cover

Best overall

CAMPLUX Camplux BW264BC 10 L gas water heater with rain cover
8.6/10about £289.99
View offer
CAMPLUX Camplux Climatech 4 GX318NG natural gas water heater

Alternative

CAMPLUX Camplux Climatech 4 GX318NG natural gas water heater
7.1/10about £179.99
View offer
CAMPLUX Camplux AY132B 5 L portable gas water heater

Preis-Tipp

CAMPLUX Camplux AY132B 5 L portable gas water heater
8.5/10about £150.44
View offer
On this page
  1. 1.Outdoor LPG or indoor natural gas
  2. 2.Flow, rise, and pressure
  3. 3.What this Amazon set costs
  4. 4.When a Gas Safe engineer takes over

Outdoor LPG or indoor natural gas

An outdoor LPG water heater stands in free air, lights from batteries, and has no balanced flue. The Camplux AY132B is that machine here: 5 litres a minute, 10 kW, a 37 mbar propane regulator in the box, and about £150.44. In England, Wales, and Scotland, regulation 30 requires a room-sealed appliance in a bathroom or shower room. A carbon monoxide alarm does not shut the gas off. The GX318NG describes a 60/100 mm balanced flue, 12 litres a minute and 24 kW, at about £179.99. The BD300NG bullets put it on a balcony or in a kitchen with a 108 mm exhaust, while the title also says bathroom.

Flow, rise, and pressure

Litres a minute here are usually a mild-weather figure, often around a 25 °C rise. A plumbing rule of thumb, as set out by PlumbRevise, puts about 24 kW at roughly 9.8 litres a minute for a 35 °C rise. That is a sizing guide, not a test of these Amazon units. The AY132B at 10 kW can be a mild-weather rinse. The BW264BC at 20 kW and 10 litres a minute gets closer to one outdoor shower. The BE158BP60 prints 6 litres a minute and 37 kW, which do not describe one duty. Several outdoor listings start at 0.25 bar, so a garden tap often works and a water butt often does not. The BE158BP60 and the G10 Pro include a pump. One review says that pump did not run.
CAMPLUX Camplux BW264BC 10 L gas water heater with rain cover

Testsieger

CAMPLUX Camplux BW264BC 10 L gas water heater with rain cover
8.6/10about £289.99
View offer

What this Amazon set costs

These prices are an amazon.co.uk snapshot on 15 October 2026. About £74 to £160 holds both Gearpass listings and the AY132B. The £74.13 Gearpass is 3.4 from 19 reviews and never names 37 mbar. A review says the reducer does not fit European bottles. About £180 to £220 covers the pumped Gasland units, both indoor Camplux models, and the BW158BC. That star line is 4.4 from 518, but the written reviews match the BW264BC file. The BW264BC is about £289.99, with its own 4.4 from 519 reviews. Named picks are on the best gas water heater page.

When a Gas Safe engineer takes over

Clipping a camping shower to its own propane cylinder, outdoors, is a different job from cutting into a house gas pipe. Paid domestic gas work in Great Britain is for a Gas Safe registered engineer. The public line to check a card is 0800 408 5500. Hand the job over for a fixed gas supply, a flue, a fuel conversion, a smell of gas, or an appliance a landlord provides. Landlords arrange yearly checks on appliances they provide and keep the record for two years. In England, from 1 October 2022, a relevant landlord also fits a carbon monoxide alarm for a fixed combustion appliance other than a gas cooker. Pressures are on the LPG or natural gas page. For a pitch, start from the portable gas shower for camping.

Common questions

Should I buy an outdoor cylinder shower or an indoor heater on the gas main?
Buy the outdoor shower when the burner will stand in free air on propane or butane. Buy an indoor heater when the listing describes a suitable flue and a Gas Safe engineer will commission it. In this set the AY132B is the outdoor 5 litre propane unit at about £150.44, and the GX318NG is the indoor listing with a 60/100 mm balanced flue at about £179.99. Sorting by stars follows the camping units, because that is where the longer review counts sit.
Does a bathroom need a room-sealed gas water heater?
In England, Wales, and Scotland, regulation 30 requires a room-sealed appliance in a bathroom or shower room. An instantaneous heater must be room-sealed or have a shutdown control before fumes build up. A portable cylinder heater in this set is not that appliance. The BD300NG title mentions a bathroom, while the bullets say balcony or kitchen and a 108 mm exhaust. Use the flue description, not the bathroom word in the title.
Do I need a pump for a water butt?
You need one if the butt cannot deliver the start pressure. Several outdoor listings here start from 0.25 bar, which suits a garden tap and leaves a static tank short. The BE158BP60 and the G10 Pro include a pump. The AY132B and the BW264BC do not. Test a supplied pump on the first fill, because one BE158BP60 review says the pump did not run. A pump moves water. It does not, by itself, heat a freezing inlet.
Who has to fit a fixed indoor unit?
A Gas Safe registered engineer does paid domestic gas work, including a fixed heater, a flue, and any recommission after a fuel change. Check the card. Clipping a supplied regulator to a cylinder is the outdoor job, and it is the wrong sequence for house pipework. If you smell gas, stop and use the emergency service.
Why is the cheapest listing a poor shortcut?
The Gearpass outdoor unit at £74.13 has 3.4 from 19 reviews. The page places a tankless flow beside an 18 litre capacity field, and a reviewer says the reducer does not fit European gas bottles. No 37 mbar figure is printed. The short sample also includes failed ignition and a gas smell. The AY132B costs more and names the regulator that listing leaves out.

Related pages

Gas boiler comparison

Gas water heater

Best gas water heater: outdoor pick and who to skip

Portable gas shower for camping: where it may stand

How to use a portable gas water heater, step by step

LPG or natural gas water heater: pressure and flue

Sources

Public UK sources and the amazon.co.uk listings used for this comparison, last checked on 15 October 2026.

  1. Gas Safety (Installation and Use) Regulations 1998 (retrieved 15.10.2026)
  2. HSE: Gas safety in the home, FAQs (retrieved 15.10.2026)
  3. HSE: Gas safety for landlords (retrieved 15.10.2026)
  4. HSE: Check a gas engineer (retrieved 15.10.2026)
  5. Smoke and Carbon Monoxide Alarm (England) Regulations 2015, regulation 4 (retrieved 15.10.2026)
  6. GOV.UK: Gas types and supply pressures in the UK (retrieved 15.10.2026)
  7. Liquid Gas UK, Consumer Guidance Sheet 39 (retrieved 15.10.2026)
  8. nidirect: Carbon monoxide dangers if camping, caravanning or boating (retrieved 15.10.2026)