Instant vs Storage Water Heaters in Singapore

Water Heaters Fall Into Two Categories – Storage and Instant

Instant Heaters

Instant water heaters are also known as tankless water heaters. They provide an unlimited supply of low-pressure hot water when needed, without using a storage tank. Here are some examples of instant heaters available in Singapore:

1. Instant Water Heater

 

  • Type: Instant, reduced water pressure
  • Single point, one heater for one bathroom
  • Runs on electricity
  • Price: $260+

2. Multipoint Water Heater

 

  • Type: Instant, reduced water pressure
  • Multi point, max 2 bathrooms
  • Runs on electricity
  • Price: $260+

3. Gas Water Heater

 

  • Type: Instant, reduced water pressure
  • Multi point, max 2 bathrooms
  • Runs on gas
  • Price: $390+

Storage water heaters (HDB and apartments)

Storage water heaters come with an insulated tank. A fixed quantity of pre-heated water is stored in the tank and available to you on demand. They are sized according to your usage. These are some popular storage heaters.

4. Electric Storage Water Heater

 

  • Type: Storage heater, high water pressure
  • Multi point, max 3 bathrooms
  • Runs on electricity
  • Price: $430+

5. Gen 6 Digital Storage Heater

 

  • Type: Storage heater, high water pressure
  • Multi point, max 3 bathrooms
  • Runs on electricity
  • Price: $620+
  • Energy saving: 10%

6. Gen 8 Digital Storage Heater

 

  • Type: Storage heater, high water pressure
  • Multi point, max 3 bathrooms
  • Runs on electricity
  • Price: $900+
  • Energy saving: 10%

7. Heat Pump Heater

 

  • Type: Storage heater, high water pressure
  • Multi point, max 3 bathrooms
  • Renewable energy heater
  • Price: $2,700+
  • Energy saving: 80%

Floor standing storage heaters

Floor standing storage heaters are mostly used as central water heaters in landed homes. They produce hot water at high water pressure and can support up to 10 bathrooms. These larger units are over 100 litres, can be installed at ground or roof levels and some are even weatherproof.

8. Integrated Heat Pumps

 

  • Type: Storage heater, high water pressure
  • Supports 4 to 7 bathrooms
  • Renewable energy heater
  • Price: $5700+
  • Energy saving: 80%

9. Heavy Duty Heat Pumps

 

  • Type: Storage heater, high water pressure
  • Supports 10+ bathrooms
  • Renewable energy heater
  • Price: $9200+
  • Energy saving: 80%

10. Solar Heaters

 

  • Type: Storage heater, high water pressure
  • Multi point, max 6 bathrooms
  • Renewable energy heater
  • Price: $7500
  • Energy saving: 50%

How to choose the RIGHT water heater?

There are no right or wrong answers. What matters is
What is important to you.
1. Water Pressure
2. Consistent Hot Water
3. Rain Shower Compatibility
4. Maintenance 
5. Cost
6. Energy Saving
7. Space Requirements

1. Water Pressure

Everyone wants good water pressure. But did you know the type of heater you choose affects water pressure?

Instant Heaters are Pressure Reducing

  • Instant heaters are pressure reducing systems.
  • They need to slow down the water flowing through their system to heat it up instantly.

Below is an example of how an instant system works. Water comes in from PUB mains at say 10 lit/min. The water passes through a flow restrictor and gets reduced to 4 lit/min. The lower pressure water passes through the heater to get heated.

Pressure-Reducing Water Heating System in Singapore

Instant heaters are pressure reducing systems

 

Storage Heaters Deliver High Water Pressure

  • Storage heaters are non-pressure reducing systems
  • They support all types of rain showers 
  • They support simultaneous showers for 2 to 3 bathrooms

Boost Your Water Pressure: 4 Must Know Water Pressure Facts in Singapore

Below is a diagram of how a non-pressure reducing storage heater works. Cold incoming water from PUB mains is fed into the tank at say 10 lit/min. At the same rate, hot water is released immediately at 10 lit/min. The system does not require a pressure reducer. 

Non-Pressure Reducing Water Heating System in Singapore

Storage heaters are non-pressure reducing systems

2. Consistent Hot Water

What is Consistency?

Consistency is how well a heater can maintain a steady flow rate of 38ºC of warm water. 38ºC is the average hot water temperature for showers. 

As storage heaters are drawing from a ready source of water, they can deliver a higher consistency of hot water. Instant heaters on the other hand are heating on the go, so their hot water consistency is lower. 

The higher the flow rate, the better the shower experience.

Unique situations

Cold Weather: When our weather drops to 21ºC, instant heaters cannot produce 38ºC of water. When incoming water temperature is lower, instant heaters cannot bring the temperature up as fast.

Concurrent Baths: For multipoint and gas heaters, users may experience a water pressure drop when two baths are in use.

4. Maintenance

Water Heaters are the highest wattage appliances in your home. For your safety, maintain them regularly. Heaters with poor maintenance fail fast and pose a risk.

Instant heaters should be checked every year. Watch out for loose electrical wiring, ELCB trips and old wires.

 

If you are using a storage tank, it is advisable to do a tank flushing every 3 years. This will clear out sediments that have accumulated in the tank so you can shower with cleaner water. 

Maintenance may cost around $130+ but if it keeps you safe, it is money well spent. Well maintained tanks can last over 10 years.

 

Renewable Energy Heaters

Maintain solar heaters every 6 months for best results as dust that collects on the panels will affect efficiency.

If you have a heat pump, they can be maintained every year. Maintenance for large central heaters are around $200+

3. Rain Shower Compatibility

Everyone wants a rain shower these days, but it is not enough to just BUY a rain shower. You also need to pair it up with a suitable water heater. Otherwise, you will just get a drizzle.

Instant Heater ‘Rain Showers’

  • These are not real rain showers, they are instant heater shower heads specially designed to look like rain showers because everyone wants a rain shower these days.
  • The flow rate of an instant heater is too low to feed a real rain shower.
  • Real 15cm diameter rain showers require a storage heater to operate
  • Cost: $420+

Instant PUMP Heater ‘Rain Showers’

  • Minimal increase in water flow
  • Not a real rain shower
  • Pump has been reported to be quite noisy
  • Price: $300+

Rain Showers Should Be Paired With a Storage Heater

  • If you buy a 15cm type rain shower, you should match it with a storage heater.
  • Storage heaters produce the high-pressure, piping hot-water shower effect that 5-star hotels have.
  • Choose the right size. The smallest storage heaters are 15-lit but you will only get 3 minutes of warm water out of them, hardly sufficient for a shower.
  • The most popular size is 40 lit. This will give you 8 minutes of hot water run-time.

 

Steam effects, rainshower, waterfall shower in Singapore

Steam effects, rainshower, waterfall showers produce best results when combined with a storage tank supply.

5. Initial Cost

HDB BTO, 2 Baths

These are the approximate heater prices for a BTO, including installation. The higher the technology, the 

Instant Heater $600 (qty: 2) 

Gen 1 Storage Heater $430 (qty: 2) 

Gen 6 Storage Heater $650

Gen 8 Digital Heater $900

Heat Pump $2,800

Resale HDB, Private Homes

Need a cost estimate for resale HDB or your private home? They’re not provided here as there are too many variations in layout. For us to understand your needs better, do drop us a WhatsApp Message we will be glad to assist.

7. Space Requirements

HDB BTO

  • Electric instant heaters can fit into any BTO bathroom
  • Gas heaters are usually installed in the yard or a well-ventilated space
  • Storage heaters can fit into any BTO bathroom, up to 50 lit
  • Heat pump are usually installed in the yard
HDB Resale or Private

Varied layouts. For guidance, send photos and measurements across to our WhatsApp line and we will be glad to help.

6. Running Cost

A water heater’s running cost is based on its wattage and usage time.

The Average Person’s Running Cost

The average water heater runs at 3000W, so if we use this energy calculator, we can see that the average person uses around $190 in heating a year.

For gas: A gas heater consumes as much as an instant water heater. Use 3000 watts for your calculation.

 

If you really want to save money, you can:

  • Use a digital heater and turn down your thermostat. Save 10%
  • Use renewable energy heaters. Heat pumps save up to 80%
  • Use renewable energy solar heaters; save up to 50%

Digital heaters, Heat pumps and solar save a lot more, because they have better technologies. But why do solar heaters save less than heat pumps? Read this article to find out more.

Conclusion: Instant or Storage?

The shower is one of the few places we can relax and unwind. Whether you prefer quick showers or long steamy ones, there is a suitable water heater for you.

  • There are no right or wrong answers.
  • Pick a heater that most suits your lifestyle. 

We advise you to start off with a heater quiz if you are unsure.

 

Other related articles:
How long do storage heaters take to heat? 

Did you know that if you use your storage heater daily, you may not have to wait for hot water at all!

 

 

Gas vs. electric heaters

Gas heaters are also pressure reducing systems. If showers in both bathrooms are running at the same time, users will feel a flow rate drop.

 

 

5 ways digital heaters saves you time and money

From our range, the most popular water heaters for HDB are digital heaters while heat pumps take top spot for private housing. Find out why.

Frequently Asked Questions About Instant Water Heater vs Storage Water Heater In Singapore

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