Decision Time: Single Heat Pump or Dual Installation? Expert Guidance on this Crucial Choice

In the quest for energy-efficient home heating solutions, heat pumps have emerged as a popular choice. However, it's essential to understand their limitations and potential solutions when considering a home renovation.

Firstly, it's important to note that alternative systems such as bivalent or hybrid systems, which combine a heat pump and a boiler, are not eligible for the Boiler Upgrade Scheme grant.

Heat pumps, like the 16kW air source heat pump, often deliver around 11kW of energy in the worst-case scenario. This means they may not be as effective as gas or electric boilers in extreme temperatures.

Most air source heat pumps are sized at an ambient air temperature of 7°C and a delivered water temperature of 35°C. However, for homes with higher heat requirements, a larger home than 300m2, or properties with specific high heat loads such as swimming pools or hot tubs, more than one heat pump may be necessary.

A cascaded system is one way to install multiple heat pumps, where one heats up water and then passes it to the next to heat it further. Another option is to fit a larger heat pump on a more powerful electric supply, such as three-phase electricity.

Installing more than one heat pump in a dwelling can be beneficial in larger apartments or buildings where heat distribution is uneven or where multiple heating zones exist. This allows for better temperature control and efficiency. It is also advantageous in hybrid systems to combine heat pumps with other heat sources to ensure supply security, particularly in very cold conditions or in older buildings where a single heat pump might not meet all heating needs.

However, careful control management is required when operating more than one heat pump, especially if they are delivering heat together. This is to ensure they are working efficiently and not wasting energy.

An interesting alternative to installing two heat pumps is to use Exhaust Air Heat Pumps (EAHP) or micro heat pumps, which are smaller heat pumps built into the hot water cylinder. These draw stale, humid air from the bathroom, kitchen, or ensuite and extract heat from that air before expelling it to the atmosphere outside the home.

If the heat loss for an old property is higher than the heating capacity of a single heat pump, a second heat pump could be added. However, it's important to note that two outdoor heat pumps would require specific planning permission, as a single air source heat pump often falls under the General Permitted Development Order (GPDO).

In conclusion, while heat pumps may not deliver the same amount of heat as gas or electric boilers, they offer advantages such as increased flexibility, reliability, and potentially lower operating costs. However, they do come with higher installation complexity, greater space requirements, and increased initial investment. It's crucial to consider all factors when making an informed decision about heat pump installation during a home renovation.

Decision Time: Single Heat Pump or Dual Installation? Expert Guidance on this Crucial Choice