If you have a new account but are having problems posting or verifying your account, please email us on for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact

HRV maintenance - what can go wrong ?

  • 16-07-2010 10:52pm
    Registered Users Posts: 16

    Interesting reading all the threads on MHRV.
    Most installations seem to be relatively new.
    In terms of maintenance, I know that the filters have to be cleaned/replaced regularily.

    However my question is:
    - what is the likely lifetime of the fan motors before they need to be replaced ?
    - if they need replacement, how expensive are the parts/labour to do this ?

    The reason I ask is that my QS mentioned that the motors need replacemnet, or at least he's seen enough of them break down.


  • Registered Users Posts: 16 struggling1

    Any replies?

    No HRV supplier will admit that anything much goes wrong with their systems, so I was looking for peoples typical experience with these devices.

  • Registered Users Posts: 551 ✭✭✭Viking House

    We installed 9 MHRV systems last year and last winter we found the supply air coming back in at 14 degrees from some of them. The air was extracted from the coldest rooms in the house which were the bathrooms and utility room and by the time the air went through the heat exchanger and back into the house the temperature had dropped to 14 degrees.
    Most HRV systems have both motors running at the same speed and rely on having the same airflow moving through heat exchanger to maintain efficiency. When the wind blows or when a door is opened the efficiency of these machines can drop by between 10 and 15%.
    The efficiency figures from most HRV systems includes the heat from the motors so if you use crap motors you will get higher efficiency figures.
    These issues and the requirement to clean ductwork regularly has led us away from centralised MHRV to using individual ductless units.

  • Registered Users Posts: 648 ✭✭✭PeteHeat


    Based on my own research which goes back long before these systems were introduced to Ireland I have to agree with Viking House.

    The maintenance issues are still an unknown quantity, I am sure there are good systems available, unfortunately even the prices don't reflect the true quality.

    Probably not too bad in a bungalow where the duct work is easy to get at and worst case take it out to clean it, replacement motors should be easy enough to source for many of the systems I have seen.