Reverse Cycle Heating and Cooling - New Home Recommendations

• 

  JIMB0 on 22/08/2024 - 16:25

  +6

  You'll only need to run the down stairs unit in winter as warm air rises and vice vera in summer. 2 separate units gives you some redundancy.

  • 

    niish150887 on 22/08/2024 - 16:29

    We were going to add a wall controller upstairs if we proceed with one unit

    • 

      lgacb08 on 23/08/2024 - 19:47

      Wall controller can only helps so much, ideally separate return air duct for each level. 2 separate systems will completely eliminate the problem.

• 

  sumyungguy on 22/08/2024 - 16:28

  Where approximately do you live and do you have solar? This will impact your decision

  • 

    niish150887 on 22/08/2024 - 16:29

    Live in Melbourne

    • 

      sumyungguy on 22/08/2024 - 16:42

      Being a custom home, do you have advice from an architect? Builders tend to recommend whatever returns the biggest margin

• 

  Taro Milk Tea on 22/08/2024 - 16:32

  -1

  who is the builder?

• 

  tanksinatra on 22/08/2024 - 16:51

  What sort of cost?

• 

  cashless on 22/08/2024 - 16:55

  +1

  40 square what?

  • 

    niish150887 on 22/08/2024 - 16:57

    +1

    372 square meters

  • 

    CheapandUsed on 22/08/2024 - 18:53

    +1

    What are house squares or builder's squares?

    Weirdly, I can imagine how big a 40square house is, but 372sqm is meaningless to me… Even though I've only ever known/used metric.

    • 

      ripprind on 24/08/2024 - 13:27

      "squares … are the most common measure of house size used in Australia. "
      Is that true? The Most common?
      I've worked as a carpenter in NSW for 10 years. Building residential from start to finish and have never come across this measurement 🤷‍♂️🤔

• 

  Ocker on 22/08/2024 - 17:57

  +1

  We have a 19kW Actron system with 7 zones. One master wall unit and each zone has its own wall unit to set temperature. All done by a WiFi remote control unit.
  A new build will be energy efficient and not like out 98 year old house. On a really (really) hot or cold day the system will consume anywhere from 8kW-10kW per hour. Having less zones operating will reduce this usage, albeit not by a proportionate amount. Note, that is a net usage, after any solar feed-in that occurs.

  Would go the Actron router rather than 2 Daikin units

• 

  dtc on 22/08/2024 - 19:01

  Actron are excellent and you can zone down to a really small area. You will find its more efficient to run the Actron across both floors than running both Daikin systems at the same time; and the Actron is probably going to be about the same efficiency as running a single Dakin to heat/cool only one floor (because you can zone the Actron down to the same level as the Daikin is running). Actually the Actron is probably marginally better (better COP)

  But two units does provide some redundancy

  What is the cost differential?

• 

  candobetter on 22/08/2024 - 22:43

  We have a 17kW ActronAir refrigerative cooling add-on in a similar-size double-storey house. The problem with one large system is that if it breaks, and it tends to break at the most inappropriate time around Christmas/New Year, you have no cooling at all. We've been through this a few times. If the outside temperature rises above 38 degrees, it starts working harder and harder, then breaks. We've repaired it a few times over our 15 years of ownership. One time it was a motherboard failure, and we couldn't find a technician to attend during the Christmas break for two weeks. Imagine 40 degrees outside, 35 degrees inside, everything is melting at home, can't do anything. It was a nightmare! Go for two systems; redundancy is a thing!

• 

  areustillpretty on 23/08/2024 - 02:10

  +4

  Multiple splits might be better? I had two neighbours where one had central refrigerated system and the other had multiple splits like 5-6 of them. The one with central system had to go through hell of a summer due to the breakdown and the parts wouldn't arrive in 4 weeks. The other with multiple splits got a cold from being too cold. Go figure.

  • 

    stickingly on 23/08/2024 - 09:10

    This.
    My house has ducted aircon and I much preferred the split systems we had in the previous house

  • 

    sumyungguy on 23/08/2024 - 09:25

    I too did this. Pre-plumbed splits, conceptually more efficient because you only condition the rooms that are in use. Redundancy is welcome as I had to wait two months for a warranty site visit in peak summer; likely because commercial gets priority over domestic. If I was in Melbourne I'd do hydronic in the bathrooms and main open-plan living dining area; with all splits or a combo of splits & ducted everywhere else. However a contemporary Green Star rated house may work fine with ducted.

  • 

    dtc on 23/08/2024 - 11:34

    +1

    splits are ugly AF though

    • 

      areustillpretty on 23/08/2024 - 17:27

      Yes, I could see those ugly outdoor units and pipes from my windows. But once you're at home you can't see it, right?

      • 

        ozbargainsam on 23/08/2024 - 18:25

        Out of sight, out of mind. Right?

        Like, why even paint the outside of houses? Why keep your garden tidy? There's so many analogies you could make

      • 

        dtc on 24/08/2024 - 13:02

        Indoor split units are ugly AF.

• 

  scrambledeggs on 23/08/2024 - 06:56

  +1

  2 separate units is definitely what I would go for, if a gecko fries your outdoor unit you will at least still have some air con and probably more efficient to run two smaller units.