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Godoh
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Joined: 26/09/2020
Location: Australia
Posts: 515

Posted: 09:50pm 25 May 2025

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Hi Roger that looks great, the sheet metal work looks fine. When we don't have a bender or pan brake to work with, well improvisation is the way.
Things are only wrong if they don't work and that looks like it will work fine
fantastic project.
I hope you get enough sunshine in winter where you are for it to save a lot of heating bills
pete

rogerdw
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Joined: 22/10/2019
Location: Australia
Posts: 896

Posted: 01:57pm 26 May 2025

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Thanks Pete. Yeah I was very happy with how it turned out and think it will do the job ok.

I keep looking at folders and guillotines etc ... but I'd use them that rarely I really can't justify buying one ... and then have to find room to keep them between uses.

I'm very confident of enough sunshine during winter to make this worthwhile. The original prototype is into its 5th season of use already and still does a great job. I cant wait to try this one out and see what she'll do ... especially seeing it's over three times bigger. Hopefully it won't be an anti climax.

Cheers, Roger

Godoh
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Joined: 26/09/2020
Location: Australia
Posts: 515

Posted: 09:44pm 26 May 2025

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Hi Roger, I made a small sheet metal folder from scraps of steel I had lying about.
It is bolted to my bench, it only does metal up to 600mm long but has had quite a bit of use. I find it really handy.
I just used a heavy piece of angle iron for the base. And another piece for the folder with two pieces of pipe welded on for handles.
Good luck with getting the heater installed.
Pete

rogerdw
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Joined: 22/10/2019
Location: Australia
Posts: 896

Posted: 04:08am 27 May 2025

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Yeah I'd often thought of building one too ... but have so many of those projects in my mind and a heap of others half done and abandoned. When I've finished my generator off and this air heater, maybe I could tackle it.

We're gonna need heat sooner than later ... so the heater is top priority at the moment.

And some good news ... I heard of another crane guy one town over, who only charges $125/hr and who likes cash, so is negotiable ... especially if he has a couple jobs to do over here ... so it sounds like it might be a lot more reasonable to have it craned on.

Cheers, Roger

Davo99
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Joined: 03/06/2019
Location: Australia
Posts: 1584

Posted: 01:09pm 04 Jun 2025

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Great progress mate.
20 Kw is substantial heating power and even if it's a bit overcast and you only get 10KW, between this and the solar you won't be cold.

I had my Ducted AC replaced about 2.5 years ago. The old one was still working byut was undersized for the house to begin with.... typical of the guy that built the place whom we bought it off.
It was useless in winter and being the only real heating, was not good. Would just freeze up and run flat out doing nothing.

I got the largest samsung they make in single phase which pulls a max of 5 KW on the AC side. It was recommended as an alternative by my mate who does AC to Fujitsu or Daiken. Been very happy with it and I said to my mate, only seems to use about 2/3rds the power of the old one which he said would be about right with the better efficiency. Even on 45o days it will make the house too cold if you crank the cold out the thing.

I'm glad to see this finally coming together. If the prototype hadn't worked so well you would have done it sooner! :0)
Are you going to leave the small one in place and run them together or does that have to come down?

rogerdw
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Joined: 22/10/2019
Location: Australia
Posts: 896

Posted: 12:03am 05 Jun 2025

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Thanks Dave, and good to see you here again.

If I had unlimited funds I'd replace the aircon straight away and see how well the heating works ... but seeing I'm in this deep with this unit I need to see it out. And you're correct, if the old one didn't work as well as it does ... I'd have had to do something sooner ... or keep with the wood.

Speaking of wood, I lit the fire for the first time this season on Sunday ... so we've got this far into the season with just the air heater, underfloor heating via solar plus a couple of normal resistance heaters. And all off-grid at that too.

Yesterday I poured 32kWh into just the floor alone ... plus had the two 2,300 watt heaters running for the same time. I had a couple of wifi switches put in the meter box so I can turn them on or off from the workshop. Very handy ... and they also monitor the power useage. Both are 3,000 watts. In the month the switches have been in, we've used 153kWh for the floor alone.

My plan with the original was to transfer it to the workshop. Just hang it vertically on the wall and cut a 6" hole either end for 90 degree elbows. I had started to think that with all this solar I'd just use a reverse cycle aircon ... but with just 43 watts for the original airheater fan ... and the fact it runs as soon as the sun shows up ... often at 7.30 am ... I have to try it there as well.

Of course I have to rebuild it because it is fairly badly distorted. I can't remember who it was (haha) but someone suggested I run it on a hot day to see what sort of heat it would put out ... and of course being pretty gullible I decided to give it a try.

One hot day I ran it for a minute or so and was surprised that it wasn't any hotter than I'd seen before ... so a bit of an anticlimax. Anyway a few weeks later I walked past and noticed the endcap off the hot mainfold was lying on the ground. Once I looked at it, the tube had collapsed by a couple inches from just that minute or so of heat and with the cap popped off was just pumping outside air into the room.

I thought it was stuffed, but when the cool season turned up, I just taped it up and kept it going. Not too much later, from the pressure of everything being out of alighnment, one of the tubes broke ... but with my excellent taping skills, I had it bypassed in no time.

The lower pipe used to be the same shape as the top one.

Edited 2025-06-05 10:11 by rogerdw

Cheers, Roger

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