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Does anyone have any info on LPG fired boilers? We are semi rural with no mains gas. I was thinking of putting a wood fired boiler in the living room connected to hydronic radiators. But starting to think I cant be assed storing the wood and lighting the fire.
Anyone know if the LPG bottles workout too expensive?
Using the Immergas HE35 as an example, LPG consumption varies from 130Mj/h at max and can modulate down to 30Mj/h when just ticking along and maintaining water above a minimum temperature.
The following are bottles you can manage without too much difficulty in moving around without material handling aids
1kg of LPG works out to be 49Mj
8.5kg (9kg bottle) of LPG works out to be 416Mj
45kg of LPG works out to be 2205Mj
You could go with a 210kg bottle which works out to be 10290Mj.
After this you'd be looking at 500kg or 1T+ stationary tanks which gets refilled from a truck.
I hope this gives you an idea of what a boiler could use and how often you would need to fill or swap the bottles.
Have you thought about using solar water heaters to heat the water as much as possible and only using the gas boiler to emper the water when it falls below a minimum temperature, say 65 degrees?
Hey Bels,
Thanks for taking the time to post all that great info.
Looks like LPG will be cost prohibitive to run....
I have been thinking of all the options, we are building a new house and have spent a lot on things like treated timber extra insulation, sisalation etc. So funds are starting to run low.. Ideally I would have a large storage tank, solar, and geo heat pump as we are on 10 acres. But once I started pricing it up I freaked out. Also it seems that Australia doesn't have the best of what's available else where in the world, although this is changing.
At this stage I am thinking of running all the pipes for the radiators myself prior to the gyprock. That way it's all there for when I decide what way to go. A wood fired boiler seems like a good option in the interim.
Cheers again.
So going by those numbers you'll use approx 1kg per hour running at min consumption.
Yep may need to keep an eye out for a second hand LPG tanker, and tune the boiler to run on auto gas...
So going by those numbers you'll use approx 1kg per hour running at min consumption.
Yes quite possibly. What I still can't work out is if that 30Mj/h is for the boiler constantly running at minimum for the hour or if it is cycling on and off.
For curiosity sake, what's the consumption of your boiler like over an hour when your house is up to temperature?
Edit: my bad, didn't realize you had a wood fire boiler.
Why the preference for gas? Considering gas prices are only going to climb up more in the future.
In the work that I do (building services engineer - medium to large construction), we are moving away from gas for water heating and shifting towards solar thermal with gas or electric boost, or using waste heat from air con ground source heat pump. You're right, gas prices are going bananas, even more so than electricity. A few extra bucks upfront can repay itself very quickly in lower running costs.
For curiosity sake, what's the consumption of your boiler like over an hour when your house is up to temperature?
Edit: my bad, didn't realize you had a wood fire boiler.
Lol yes that's on our acerage but in the burbs I'm putting gas.
It would however take lots of my own KJ's to cut the timber!
Has anyone done the sums gas vs electricity (no heat pumps). I was looking at electric but was laughed at because of the high KW usage of the boiler.
There is no way you going to get 35kw out of solar panels on a residential roof.
mixo
P.s also looked at heat pumps/solar/heating/water but the upfront cost is horrendous.
35kW refers to the mechanical output energy, not the input energy.
No one seems to have mentioned pellet wood boilers,they are supposed to be very efficient, but the pellets are expensive but you don't need much, google it it might be cheaper than gas.
Cheers
Pellet boilers are another option. With this option, you can actually buy machines that add onto the boilers that make the pallets. What you do is just purchase wood sawdust and the machine pelletises it and feeds it into the combustion chamber.
We would have gone that way if we didn't have 5 acres of trees to use. The fires themselves aren't too pricey.
P.s also looked at heat pumps/solar/heating/water but the upfront cost is horrendous.
It will looks horrendous if you look at the system in isolation. The benefit of these types of solutions comes from taking an integrated approach. For example, I recently designed the electrical and mechanical services for a 4 bedroom care house for disabled people - basically a very large 4 bedroom house, built to a commercial grade.
Anyway, I used solar PV-T panels (photovoltaic and thermal), geothermal heat pump ducted air conditioning, and a hot water storage system that uses thermal energy from the PV-T panels and waste heat from the geo heat pump (it also has an electric 3.6kW element for boosting, this could be gas too).
When we did true cost analysis of this integrated solution, compared to a "business as usual" solution of a Daikin ducted inverter air system, a 315 litre Rheem rooftop solar HW system, and 2.5kW of solar PV, the net cost premium for the geo/PV-T solution was only about 20% more, but the 20% extra cost was recovered in energy savings in less than 3 years. After those 3 years, the energy savings compared to the "business as usual" approach will be about 30-40%.
Got my second quote and for the same price of the first i get 3 towel racks and 2 panels extra.But they quoted me on a non condensing unit which I don't get(price is lower by 800 bucks)
Everything is Bosch. Anyone had experience with bosch panles/thermostats and boilers?
Also theyplan on putting a panel under the kitchen island. it has a 300 mm overhand.Doesn't this effect the panel operation? anyone done this and it works o.k to heat that area of the room in front of the island?
And yes still not sold on the towel racks!
Mixo
Is that quote from Hydrotherm in Thomastown?
The efficiency difference between Condensing and std is about 9-10% so if you spend $250 per quarter it will cost an extra $25 for a standard boiler. Do the math after a few years it will start costing you money.
Also I'm not a fan of radiators on island benches. They should be as close to windows as possible. Personally I think it would look silly. I'd rather have the option to sit at the bench.
The radiator will stick out about 100mm
Thought so. They used to sell the other brands but have now changed to Bosch.
Just one word of warning about any company, if they only offer one range of product they will only say good things. Look for systems or referrals from people that have had them in for at least 10yrs.
I need to replace my hydronic boiler which heats my slab and my water. Can anyone recommend a brand that they have had a positive experience with. I have a double storey home and a few bathrooms. I have been told that I need to split the system so I am looking at a unit to heat my slab and another do to the hot water. Can someone help?
Probably a bit late with this reply. You definitely don't need two boilers, I hope that was cleared up before you went further. A partition device is used to split off between your panels ,that run much hotter, and the underfloor.
Or get a combi boiler with 2 separate circuits.
I am presently getting quotes for replacement of a vintage Ferrola hydronic boiler installed at my property possibly around mid 1970's. This boiler has done well! I have had quotes on Baxi and now looking at a Immergas Intec condensing boiler. I have been told that especially as I am looking at a condensing unit I should have the steel pipes beneath the house replaced with copper. I have a quote for the boiler which is dearer than Baxi but there could be various reasons for that. I am waiting now for the updated quote for copper piping. I appreciate feedback.
When I was shopping for quotes for my hydronic system, I got prices for Baxi, Immergas and Sime with Sime cheapest, and not alot of difference between Baxi or Immergas with Baxi slightly dearer but it was really the difference of loose change. I went with a package that included a Immergas condensing boiler.
Were you given a reason as to why you need to replace the pipework? Assuming you have steel radiators, wouldn't there be issues with them as well? I'm actually surprised they opted to suggest copper as I thought almost all installers installed rehau or uponor pex pipe.