Buying guide · plain English4.9340+ reviews

Storage or instant?

Both heat water. They use space, energy and capacity differently lengths, and suit different households. Plain-English comparison from a Singapore-licensed installer — and an honest recommendation for your specific home.

LEW for fixed-wiring scope Mounting + plumbing quoted separately We install both
Storage
Capacity30L
Hot supplyFinite
Best for2-bath
Instant
Capacity
Hot supplyEndless
Best for1-bath
Pick by home size, occupants, and ceiling space
Head-to-head

Side by side, no marketing.

Model-specific trade-offs, with no universal lifespan or household-size shortcut.

FeatureStorageInstant
Hot water supplyFinite stored volume; usable mixed water depends on tank temperature, inlet temperature and shower flowContinuous only while flow and temperature rise stay within the model's rated performance
SparkFlow guide service$250 storage-heater installation; confirm tank supply, support and pipe scope$180 instant-heater supply + install package; confirm included model and site assumptions
Installation variablesFilled weight, structural support, valves, discharge route, pipework and service accessMounting, flow and pressure, shower set, fixed wiring, isolation and model-specific load
Electricity bill impactHas standby heat loss; controls, insulation, set point and usage affect consumptionAvoids tank standby loss, but running cost still depends on power, flow, temperature rise and use
Hot water pressureDepends on supply, system design, pipework, fittings and simultaneous outletsDepends on incoming pressure, flow controls, shower set and rated heating performance
Reliable hot temperatureCan supply stable mixed water until stored heat is depleted; set points vary by modelTemperature can fall when requested flow or temperature rise exceeds model capacity
Space takenBulky tank (typically 50–80cm tall)Slim — wall-mounted, often above the shower
Replacement decisionCondition of tank, valves, supports, parts, warranty and installation matters more than age aloneCondition of controls, heater body, protection, parts and wiring matters more than age alone
Best forHomes that need stored capacity or simultaneous outlets after a proper demand calculationA point where the selected model can meet the required flow and temperature rise
Sizing recommendations

Pick by household, not by brand.

We size to how you actually use hot water — occupants, bathrooms, shower frequency. Not whichever unit the marketing pushed.

Instant
One shower point · predictable flow
Compare a model-rated instant heater

Check the measured flow, desired temperature rise, available electrical installation, shower set and mounting space. Occupant count alone does not size the unit.

Either
One bathroom · back-to-back use
Compare rated instant performance with usable stored volume

Use shower duration, flow and recovery rather than a fixed household rule. Either type can work when the model and installation meet the demand.

Storage
Two bathrooms or simultaneous outlets
Calculate peak demand and system layout

A storage system, separate point-of-use heaters or another designed arrangement may fit. Tank litres alone do not guarantee two simultaneous showers.

Storage
Multiple outlets · variable schedules
Use model data and a room-by-room demand plan

Compare usable mixed volume, recovery, pipe losses, electrical capacity, support and service access. Larger is not automatically better or compatible.

Quick numbers

Worth knowing before you decide.

Avg shower
35 L
for a 5-min Singapore shower
Tank reheats
15–25 min
from cold to 50°C on a 30L
Electrical load
Model-rated
LEW assesses the exact circuit
Instant supply
Endless
as long as power + water on
Frequently asked

Common questions.

Still not sure? Let us recommend.

Tell us your home size, number of bathrooms, and how many people live there. We'll come back with one specific recommendation — brand, size, price, install date.

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