How Do I Size A Hot Water Cylinder?

When selecting the size of the hot water cylinder, a simple rule of thumb is that for a typical domestic household, you should allow between 35 and 45 litres for every occupant. That said a mains pressure system can use about 18 litres of water per minute at 40 degrees Celsius if a decent quality shower head is used.

How big should my hot water cylinder be?

To put it briefly, for a family of 4 you will need: Electric Hot Water: A 125–160L tank for a continuous system or 250–315L for off-peak. Gas Hot Water: A tank of about 135–170L, however there are also instantaneous system options.

How do you measure a hot water cylinder?

Hot water cylinders come in all many shapes and sizes but are generally circular in shape and are fitted in a cupboard of some sort, with the most common location being the traditional airing cupboard. The cylinder is measured using the actual size of the copper itself and does not include the insulation around it.

What size hot water tank do I need in Litres?

The most important and easy rule of thumb is basing your hot water cylinder size on the number of people living in the house. E.g. your average 4 person household uses 250litres of hot water per day.

What size boiler do I need for a 300 Litre cylinder?

If you had a 300 litre tank, your requirement would be 19.5Kws. You now have a heating requirement of 18kw and a hot water requirement of 7.8Kw. Rounded up, this means you need a boiler with at least 26Kw output.

What size water tank do I need for a family of 4?

So with a family of 4 that has visitors staying occasionally, you could need 225,000 -250,000L of water per year. As your tank should fill up by the end of winter, you may not need a 250,000L tank but simply enough water in storage to get you through the 6-7 months of dry weather with a bit of buffer.

What size water heater is needed for a family of 4?

For a four-person family, a 50-gallon water heater is sufficient. 50-gallons is good if you’re using electricity, and 40 gallons will work for natural gas or propane. Families with more than five persons may benefit from an 80-gallon electric water heater or 50-gallon gas water heater.

How big a cylinder do I need?

When selecting the size of the hot water cylinder, a simple rule of thumb is that for a typical domestic household, you should allow between 35 and 45 litres for every occupant. That said a mains pressure system can use about 18 litres of water per minute at 40 degrees Celsius if a decent quality shower head is used.

How do you size a water tank?

You can estimate the necessary tank capacity (in gallons) based on the number of people in the house:

• 1 or 2 people—23 to 36 gallons.
• 2 to 4 people—36 to 46 gallons.
• 3 to 5 people—46 to 56 gallons.
• 5 or more people—over 56 gallons (add 10 gallons per additional person)

What size water tank do I need for a family of 5?

Water tank size for family of 5:- for a standard normal house, an estimated 200 litres per person is the thumb rule.

How many Litres is a water cylinder?

How many people does the hot water cylinder need to cater for? Keep in mind that typically one person uses approximately 50 litres of hot water a day, and the standard sizes of hot water cylinders are 135, 180, 250 and 300 litres.

How long does it take for a 180 Litre hot water cylinder to heat up?

A hot water cylinder heated by a boiler can be re-heated from cold, usually within 30 to 45 minutes, depending on the type of boiler and size of hot water cylinder.

How long does it take to heat a 300 Litre hot water cylinder?

One minute per litre, as a minimum for a modest temperature rise, so at least 210 minutes. One and a half minutes per litre to get really hot if starting very cold, so up to 315 minutes.

How do I calculate boiler size?

A good way of determining the size of boiler you need is to count your radiators around the home. Obviously the more you have, the more power the boiler will need to deliver to make sure they are all piping hot.
Count your radiators

1. Up to 10 radiators: 24–27 kW.
2. 10 to 15 radiators: 28–34 kW.
3. 15 to 20 radiators: 32–40 kW.

How many kW does it take to heat water?

Calculate the kilowatt-hours (kWh) required to heat the water using the following formula: Pt = (4.2 ? L ? T ) ? 3600. Pt is the power used to heat the water, in kWh. L is the number of liters of water that is being heated and T is the difference in temperature from what you started with, listed in degrees Celsius.

What’s the difference between a direct and indirect cylinder?

Direct and Indirect
A ‘direct’ cylinder is heated via an electric immersion and does not work with gas, oil or heat pump systems. An ‘indirect’ cylinder has coil running through the cylinder.The heated coil imparts its heat onto the fresh (potable) water in the tank that is used for washing or showering.

What size water tank do I need for a 3 bedroom house?

For most families, the number of bedrooms plus one is a good number to use for the number of people. For instance, a three-bedroom house would typically have a family size of four. Then, multiply this number by 12 gallons.

How big is the average water tank?

Generally, rainwater tanks can be classed as: Small – less than 2,000L • Medium – between 2,000L and 10,000L • Large – greater than 10,000L.

What size water tank do I need for a 4 bedroom house?

So for a four-bedroom house, you’d calculate based on having five people live there. Multiply this number by 12 gallons, and that is the FHR. So in a three-bedroom home that has four people, the FHR would be 48 gallons (4?12 gallons).

How many showers can you take with a 50 gallon water heater?

A 50 gallon water heater is the most common tank we install. It is such a common size because it can supply hot water for 3 – 5 people. Considering an average shower uses 17.2 gallons of water you can typically have enough hot water for up to five people to take a shower within an hour.

Is there a big difference between a 40 gallon and 50 gallon water heater?

The Energy Factor
The cycling losses measure how much heat is lost as the water circulates through the system.With the energy factors being equal, the difference in cost of running a 50-gallon heater over a 40-gallon heater is essentially insignificant.