Why DHR solutions are better than PIV

Ebac’s Dehumidification with Heat Recovery (DHR) is a new way of removing moisture from homes without the heat loss and higher running costs associated with the alternative method of ventilation Positive Input Ventilation (PIV). Call our team on 0333 880 3427 for further information.

What is DHR?

DHR systems, are an effective solution for addressing moisture and condensation issues in properties. They offer several advantages over other systems, such as the ability to mitigate these problems without requiring extensive ducting throughout the property. This makes DHR systems relatively easy to install.

One significant advantage of DHR systems over Positive Input Ventilation (PIV) systems is their ability to recover up to 88% of the heat from the air they extract from the property. The recovered heat is then reintroduced into the fresh, inbound air, which minimizes the amount of energy needed to reheat the air to maintain comfort.

In summary, DHR systems address moisture and condensation issues, are easy to install without extensive ducting, have low running costs compared to some other systems, and recover up to 88% heat energy.


Heat recovery

Easy to install

Low running cost

What is PIV?

PIV systems work by introducing air into the home through a central unit. The system creates positive pressure in the home, which forces moist air out through natural ventilation points like windows and doors.

PIV systems are relatively simple and inexpensive to install, making them a popular choice for homeowners looking for a quick fix to their ventilation problems. However, the major downside with PIV systems is that they also push out the warm heated air and this lost heat has to be replenished. 

Low cost


Easy to install

How much can you save by using Ebac’s DHR?

Our engineers have calculated that to reheat the warm air lost with PIV systems – it would cost £158.35 every year. Over the course of 7 years (the estimated lifespan of a PIV unit) that represents a cost of over £1,100 in wasted energy.

Test conditions / Assumptions: 

  • Heating season is from October - March (6 Months) as per "Table 5 Commission Regulation (EU) No. 813/2013", for the purposes of this illustration, the conditions have been averaged.
  • Outside RH% remains constant @ 80%.
  • Same air flow rate at all conditions for DHR to be comparable to PIV (in reality will run at lower speed)

Benefits of DHR


Easy Install

Non intrusive installation with minimal ducting 


Effective Solution

Proven to solve condensation and dampness


Super Efficient 

EC fans and 88% heat recovery minimise running costs

For further advice and information please call our team on 0333 880 3427.