Situated in a small picturesque Istrian village Ruzici, a few kilometres from the Istrian coast, Villas Bonadais a settlement comprising of 3 rental villas with independent swimming pools.

The facility owners initially planned to heat the new villas solely through air conditioning units. Due to the shortcomings that this would entail in comfort levels and long-term economy they opted for a hybrid heat pump system instead.

Gallery

Interior underfloor heating installation

The manifold

Mitsubishi PUHZ-FRP71VHA and additional multisplit outdoor unit

The plant room with TermoPlus® Hydrobox MZ for ECODAN and DHW tank

Mitsubithi indoor wall unit

The Istrian coast has mild winters and warm summers during which cooling will be important for the villas. A hybrid heat pump system was ideal for this situation as it could efficiently heat the properties during the winter and cool them during the summer.

How The System Works?

COP 7.0!

During winter the system will use the heat pump for incredibly efficient heating and Domestic Hot Water (DHW). In mild weather theair-conditioner can be used for heating and the heat pump for DHW.
During warm weather the air-conditioner will provide cooling and theextracted heat will be recycled for DHW such as shower facilities,
kitchen use, dishwashing, laundry, or heating swimming pools.

Heating and Sanitary Hot Water

The indoor heat pump heats the space via radiators, underfloor heating or fan coils. The hydrotank also produces domestic hot water autonomously during winter or by recycling heat from the air-conditioner during summer.

Air-conditioning: Heating and Cooling

The indoor air conditioner is very similar to a standard air-condition unit. Normal air-conditioners dispel heat via their outdoor unit which is a waste of energy. The hybrid system instead uses this heat to produce hot water for domestic use (dish-washing, showering, etc.)

One Outdoor unit for both systems

The outside unit replaces the need for a separate outside air-conditioning unit. This males the system even more affordable and takes up less space.

The hybrid system included the optional benefit of recouping the waste heat produced during cooling in order to heat the pool and the domestic hot water -essentially using free energy.

During winter the system will use the heat pump for incredibly efficient heating and Domestic Hot Water (DHW). In mild weather the air-conditioner can be used for heating and the heat pump for DHW. During warm weather the air-conditioner will provide cooling and the extracted heat will be recycled for DHW use such as shower facilities, kitchen use, dishwashing, laundry, or heating the swimming pools.

Since tranquility is very important in the hospitality sector, the installation needed to operate unobtrusively. Underfloor heating is completely silent and the external unit used is extremely quiet. The system components were also easy to tuck away neatly without being a visual distraction or taking up too much space.

We demanded the highest levels of comfort for our 5 stars villas but we also needed to minimize our cost of operation in the long term.

Davor Subotič, Owner, Villas Bonada

The System

Outdoor unit:
MITSUBISHI PUHZ-FRP71VHA system ECODAN Mr. SLIM +

Indoor unit:
TermoPlus® Hydrobox MZ for ECODAN Mr. SLIM + 2x 3,5 kW wall indoor units by Mitsubishi for cooling/heating. These are similar to fan coils but are connected directly to the outdoor unit.

Domestic Hot Water
300 liter TermoPlus®DHW tank

Under floor heating throughout the villas

Additional multisplit A/C systems
In some villas an additional multisplit A/C system was also added for supplemental cooling in the event demand exceeded the 7 kW provided by the hybrid system.