Domestic Hot Water
There are various domestic systems for heating water :
Hybrid systems: combine a boiler and water heater in one unit resulting in saving space.
Water heaters are used to heat your water. The most common types are:
- electric water heater which can be an instantaneous heating element or water storage heater which maintains the water at a given temperature.
- gas water heater, also instantaneous or storage, works with a gas burner which requires an annual review.
- solar water heater which heats water with free and renewable energy collected by solar panels.
- heat pump water heater which includes a heat pump that heats the water through the process of heat recovery from the ambient air.
Domestic hot water through your boiler: the different systems
Combi boilers are simpler and more economical than a boiler system + water heater
- Simplicity and space saving: a single device and a single pipe system.
- Economy: an independent heater operates with electricity or gas typically.
It may be desirable to have an independent water heater of your boiler in some cases:
- solar water heater: economic and ecological
- When the current boiler is not powerful enough to meet the hot water needs of occupants and water tanks are far from the boiler (to avoid installing additional piping).
- Instant mixed: for small homes
These systems do not use hot water. They heat the water directly, instantly, on demand when hot water is needed.
Recommended for small households (2-3 people) and small houses (one single room with shower rather than bath).
Advantages :
- Economical, not heating water unnecessarily.
Disadvantages :
- Limited by concurrent requests: it results in sudden jets of cold water in the shower for example, or warm tap water when the shower is running.
Mixed storage: for large and predictable applications
These systems use a balloon as a hot water tank, a large volume of water (between 80 and 300 liters) is heated and maintained at temperature of 45° minimum.
The idea is to anticipate the demand for hot water and maintain a constant and moderate supply of hot water. This avoids having to install a high-powered boiler.
Advantages :
- Performance: hot water all the time and immediately.
Disadvantages :
- Limited to cumulative capacity: if your home has many people, for example, once the capacity is exhausted then there is only cold water while the system is charging and heating again.
- Requires the placement of a balloon.
- This is an added expense and you need room to accommodate it.
- Health risk: the average temperature of standing water can develop bacteria.
Mixed semi-accumulation or micro-accumulation: an intermediate solution
This is the middle ground between the instant and cumulative systems, which combines the advantages of the two while limiting the disadvantages.
A hot water tank of small capacity (up to 30 liters) is integrated into the boiler. This provides hot water immediately, without waiting for the water heater. It loads quickly and can therefore cycle several times throughout the day. It is not bulky since it is built into the boiler.