Replacing Gas Ducted Heating System

So my brivis gas ducted heating system started showing errors 65 / 30… I got someone from service seeking to look at it. He assumed it was because the system was 'overheating' and replace a duct and serviced it for $700. This did not fix the issue and he now says the unit has a faulty fan that needs to be replaced for $1200….

That or he since the unit is 22 years old he can replace it for $2200 with a Bonaire mb310.

My question is

  1. Am I getting screwed?
  2. Is it worthwhile replacing the system?
  3. Is there a better system I should look at? I do value smarts and google home integration. So would be open to other suggestions if anyone had any.

Comments

  • +20

    Multiple split systems throughout the house. Despite the gas industry ads on TV, gas is on the way out.

    • Agreed - some government rebates going too, when replacing old gas heaters (here in vic)

      • I'm in Victoria… But would this use this exisiting ducts? The misso hates the look of split system head units.

        • You can get all different types of split systems - including ducted. Doubt it would reuse the old ducting though

        • Most people wouldn't use ducted these days I wouldn't think. Your ducted system would be decommissioned to get the rebate and you just close the flaps to stop the hot/cool air from escaping I suppose.

        • +1

          You generally can't use the existing ducts because split aircon needs a different size to gas. At least, that's what I was told!

        • +2

          AFAIK the splits they offer are the standard wall mount jobs.
          https://www.energy.vic.gov.au/households/victorian-energy-up…

          We have a 40+ year old Vulcan unit which I'm sure is horribly inefficient, but creates damn nice instant warmth to the house. We have split systems just about everywhere for cooling and I keep telling myself to just turn them on for heating too… especially since we have solar. Sometimes I do, sometimes I don't… but while it's working, it will still get used.

          We did have a whole house electric ducted thing in a prior life, it was just as good, although also relatively expensive to run, turns out heating or cooling a whole house (even with some zoning) is more expensive that just heating or cooling the room you are in. But it's also nice to move throughout the house without walking into the cold/hot room, especially with little kids.

          We did move to another house in the same suburb which had a couple of old splits, we did look at installing ducting again but it wasn't possible/practical to retrofit to a two story house. Instead we put in a bunch of split systems and hid the outdoor units as best we could. Despite being a larger house that the one we had moved from our power bills were waaaaay down because we really did just turn on the split in the room we were in (or where the kids were playing/sleeping). Modern units can heat or cool a single space pretty damn quickly so it's not so bad moving between spaces, although I would suggest that we would probably more congregate in the lounge rather that different rooms because that's where it was the nice temperature.

        • Not the same situation but we've just had our electrical ducted air-conditioning system replaced. They had to replace the duct between the new outdoor and indoor units (keeping it in the same roof space) but didn't have to touch the ducts in the rest of the unit.

          Probably best to ask for a few quotes (where they'd no doubt discuss with you on how best to proceed).

          • @Love a bargain: My current underfloor ducts are held together with hopes and dreams and a lot of duct tape.

            It's a catch 22… errrr 222?? It's not worth replacing the ducts unless I'm keeping the gas heater… but it's not worth replacing the gas heater with the way gas is going… but it's not worth converting to electric since I already have splits everywhere.

            • @The Hawk: Everyone's situation is different. I was responding to OP (where, unlike you, he doesn't "already have splits everywhere"), not you.

    • +3

      Exactly right - if it was going well they wouldn't need the ads 😂

    • Yep.

      I assume Op is in VIC / Melbourne
      If you need heating in winter you will need cooling in summer

      New AC is the way to go with solar panels on the roof to keep power bills down

  • +1

    I would replace it with a reverse cycle system.

    • This would require a ton of cost right to put a split system in each room?

      • It is lots expensive, yes but the most cost-effective way of heating. You can get a central heating system.

      • +3

        Start with a decent size unit in a central area of the house. The heat will reach the rest of the house, just need to turn it on earlier or better yet just leave it running all the time.

        Once the house is warm they ramp down and run much more efficiently. Works out cheaper than using gas, especially if you have solar.

      • Not every room needs one, but yeah you'd want like three of them maybe, more if you have a big house. The efficiency on these are huge though. Over 20 years you'll save money, you'll be able to have house colder in summer and warmer in winter, and if one breaks you only need to replace that one and not the whole system.

      • +3

        Yeah it is expensive to put in ducted RC. Less expensive to do splits. All the gas ducting is useless and need to be removed

        • We already have a split in the back living area… But the misso hates cold bedrooms… And like the way the gas heating heats the house and bedrooms in particular….

          • +1

            @GuniGuGu: Yeah wife here loved the gas…

          • -1

            @GuniGuGu: We have a little ceramic heater in the bedroom and we only put it on when we are changing clothes. I’m not keen on the cold sheets so I wear an Oodie to bed. If you take your arms out of the sleeves it is like sleeping in a fleecy sleeping bag. I guarantee the missus won’t be cold overnight.

            We’ve created a snug area for winter so we only need to heat a small area. We have a reverse cycle air con in that area. We reclaim the rest of the house outside Winter. If need be this area could also be cooled.

      • Not bad with the government rebate, I had my gas heater and ducting ripped out and a decent split system put in for about $4.5k last year without any cash back. I also paid them to do the disposal and the underhouse ducting didn't need to be removed. Doing the whole house (one large, 3 small split systems) would have been about $6k out of pocket if I got the government rebate. Plus there's things like mitsubishi cashback at the moment.

        $6k is a lot more than $2200, but it's a lot more efficient. Our power bill on a draughty 1970s 3 bedroom is about $200 a month at the moment, it's getting better as we do more sealing of stuff.

    • -1

      One guy from an installer said the RC doesn't work bellow about 6C outside, is it true? In Melb we're hitting 2C some days and that's when we need the hearing the most.

      • +3

        That's total BS, I'm in Canberra and have a central AC rated to -20. This week we had -6 and it was working just fine

        • Reverse cycle or regular AC?

          • @reactor-au: I am not sure what this even means in 2024. All current offerings from all manufacturers are reverse cycle, heat-pump based inverter aircons. "Regular AC" is something I think was last sold in early 90s.

            I have a ducted system that does heating and cooling, so yes it's reverse cycle

            • @ZloyKrys: Damn, and here I've been thinking if it heats but doesn't say reverse cycle/heat pump then it must be using a heating element somewhere, good to know.

      • yeah complete utter garbage. Had various RC systems here in Canberra for the last 20 years. I can assure you it would be hell if the heating cut out at even 0 degrees. most systems are rated for about -15 to -20

  • +1

    Ducted heating is so so expensive to use, I remember in winter my gas bill would be atleast $1000 for 2 months. I know the cost to put split systems in each room is expensive but it would only take 2 years of Melbourne winters to recoup cost, and the split system will last many many years. And even if you have to replace it’s so much cheaper, few hundred for a new split unit.

    I went 4 split systems and never looked back. My gas bill is now $100 for 2 months

    • +2

      does your electricty bill go up though? how much by?

      • For me running 2 or 3 splits fairly constantly adds about $30 a month to my electricity per unit

  • As a Ken Berran, we did this 4 years ago, and my wife still hates the ducted AC. Yes there is no cost to keeping the house warm as we have solar, but we have a small house at 160m and only purchased a 15kw ducted unit for approx $12k. Its worth reinstalling gas ducted system, even if its use is limited to 3 months during winter, if its cost $2k to run each year thats still cheaper than what we paid overall

    • Why does she hate the ducted AC?

  • You can replace gas ducted with ducted aircon using same duct outlets but they need to run a new ducting and larger outlets but likely cheaper than putting a split in every room. Individual splits more efficient on their own if you run one or two of them but if you need to heat the entire house this efficiency is just not there, you have to buy too many splits, they all cost money and if all running at once, can consume more than one central ducted unit. And have to have many of these unsightly units on the walls.

    Ducted AC will be much cheaper to run than gas ducted and also provide central cooling in summer.

    • Technically you can but in most cases you should be replacing them all anyway due to age

      • I specifically said needs new ducting and larger holes but can be at the same place as gas ducted so don't need to rip the walls or ceilings and can be fit under the floor

        • How do they put in new ducting for room that has very low crawling space under the house? Does it has to be have larger holes when using AC ducted?

          • @OhNoUShiz: Yes, needs larger holes for ducted AC.

            The ducting when no air in it is fairly compact and not too difficult to affix to underfloor especially if it's already got old ductwork.

    • Not really, in the other house I had 5 splits and can comfortably heat the whole house in Melbourne without worrying about the bill, except for the 7kw split the rest of them use less than 500w once they get to temp, system that size has COP around 5 is the norm. The 7kw was the big killer, a bit less efficient but still better than ducted because by design ducted eventually heat your whole house up. My current place is in warmer climate, better insulation but with new 14kw ducted, without solar cost of running it is astronomical.

      • Lol, my 25kW ducted ramps down to 700w when at temp. But it's modern and zoned. Imagine 5 splits at 200-300w each also hanging out on walls.
        7kW split will have same average EER as large ducted like 3.5 to 4

        My overall bill is 1500 in credit over year (large solar) with heating and cooling in Canberra using ducted system, idk what astronomical bills are you speaking about I don't have any

        • Lol, 700w is false reporting, how many kwh does it chew before getting to that figure? I bet it's not below 20. $1500 credit probably was 10 year old number, don't make it up mate.

          • @lgacb08: 17kW solar in the ACT with 18c FiT gives you approx 1700 aud credit for export over a year. You must be living in a state that is gas powered so your FiTs are shit.

            We had the ducted heater on today to raise from 16 inside to 22 inside over 50 minutes with about 4 degrees outside it chewed 6.75kWh and idled since then at 700w to keep it running on solar through the day. Your expectations probably based on dinosaur tech

  • I got called from these companies doing rebate with Vic gov in place. I was quoted 3200 out of pocket to replace my gas heating with 3 separate split system units with capacity of 7kw, 5kw & 3kw with centralised system. I wasn't interested as i have big house 3 units won't do for me. In the end they said under rebate they can do upto 7 units under rebate. Worth checking quote for your needs as ongoing this is cheaper than gas as others have said.

  • Ducted heating is like a vintage car — the salesman will always try to sell you on it, no matter what lies they have to throw at you, but gas ducted systems cost more to maintain, more to operate it, it's bad for your health (increased dry skin, dry eyes, circulated dust, allergens and viruses around the house);
    Bonus feature: if you have ceiling outlets, it's the least comfortable form of heating and least efficient way to heat a house since it blows hot air from above and because of thermodynamics/flotation, you have to overheat the ceiling-level air in order to make your floor-level air comfortable, and all of the air in between them, either your head will be hot, or your feet remain cold.

    Cheapest options: Get a multi-head split system under government rebate; Alternatively, if you can find a suitable location for it, multi-way bulkhead units in each living space (one side is direct the other can have a ducted outlet). Then use smaller ceramic heater in the smaller rooms like bedrooms, as needed — we use the RC during the day, and ceramic heaters on a thermostat at night.
    Ducted, zoned, reverse cycle AC is pretty expensive, but still cheaper to operate than a gas system, moreso if you add solar.

  • My 14yo bonaire gas ducted heater packed up recently. Initial tech diagnosed a Control board fault and quoted $2300 to replace the control board with no guarantee it would fix anything.

    Instead I had the existing control board repaired by someone else. Total cost around $850. Downside is it took about a month to repair, but overall I'm happy with the outcome. Melbourne eastern suburbs. Happy to pm you the contact if you're interested.

  • +2

    Error 65 / 30 is related to the motor running slow. He could have disconnected the ducts at the heater to 'unclog' it for a test. This is usually the motor fault could be just a motor start capacitor or seize bearing or the control box.

    Not sure about the new models, older Brivis gas heater has a design flaw. The control box where the brain is placed inside the unit. This is ok when it's new but as the unit age all the adhesive and plastic pipes gets brittle they start to leak. The exhaust flue gas and heated air started leaking through the gaps not just cooking the control box but also corroding the circuit board. There is a vent motor but it does not prevent hot gases passing through the control box.

    I worked on mine everytime it crap itself for the pass 14 years, it has thrown all sorts of errors and most time it narrows down to the control box or the flame sensor. The control box will need new capacitors after 8 years it's just too hot that dries to out. You might need replacement if you run the heater more often. The unisolated/exposed control box Brivis is designed to kill itself.

    Anyway if you go split, reverse cycle or those heatpump you will have much less issues. Gas was good but not anymore. Cut off gas you stop paying daily supply charges. If you are a home owner you should put aside some money for maintenance. The roof, paint, A/C, plumbing, electrics are something that needs maintenance.

    • Have a 3 year old Brivis and can already see signs of this, Brivis always seems to have control box issues… :(
      If it were up to me I would not have bought it.. but that's a diff story…
      Anyway… idk why it is so hard for them to just put the control box completely separate from the rest of the unit.. it's a big arse box sitting there anyway.
      Make a complete separate compartment that is no where near the heat sources then put long ass wires to everything that it needs to control, then at least first thing to go is just brittle wires which can be replaced easy.
      Suppose longevity of these things is not their ultimate goal though…another how cheap can we make it while adhering to a passable warranty period.

  • Can only answer #1 with absolutely certainty.. yes

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