Removing old hot water system in roof

[zacnelson]

Hi, my house was built in 1964 and has a really large gravity-fed electric hot water tank in the roof. It has long ago been replaced by your usual gas hot water system which is by the side of the house. Now, I need to place a load-bearing beam in the roof because I am changing a couple of walls, and the hot water tank is of course right in the way. What's the best method for removing it? I will have the plaster removed below, but I don't want to have to remove any tiles or rafters above.

The only solution I can think of is to cut it up in pieces with a grinder so that the pieces are small enough to drop through the joists. Is that safe? Would it be thin enough to be cut through in this way? Would it cause any explosions or anything from sparks? (By the way the tank is empty and not connected to power anymore).

Cheers,

Zac

[TommyC]

Good question.....(I have one in my roof as well)....Thinks....cutting it up with a grinder in your roof space is not a good idea, sparks, dry conditions, could be a disaster.

If you have a metal roof and a decent ladder, it might just be easier to pull 3 or 4 sheets off and lift the tank out. Having said that, i dont think I would go to that effort...why not just move it out of the way and leave it there. Unless its made of copper, in which case you might be in for a nice surprise as to its scrap value!

[Stevenp]

We had a similar situation a few years ago in the last house we owned. Just move it aside and forget about it like Tommyc suggested.
Cheers Steven

[skot]

zacnelson,
I agree with TommyC about avoiding the grinder but if I remember those HW Systems correctly you may be better to disassemble it in the ceiling...

I think the outer metal shield should be pop riveted down a join, so drill the pop rivets out and peel back the outer cover. You should be able to fold and squash this to be able to drop it through the ceiling.

Next remove the insulation material..most likely made of Glass Wool..make sure you wear gloves and face mask....place that in a plastic bag and pass it through the ceiling.

You should now be down to the inner heating tank...this should be small enough to pass between the ceiling joists. If not you may have to concider moving the inner tank to one side and leaving it there but now it should be an easier size to move.

[zacnelson]

Fantastic advice gentlemen, I am well pleased. But I'm not deliriously excited about getting covered in glass wool and working in a hot confined roof....

[peter_sm]

Get a rotary hacksaw blade from Austsaw

http://www.austsaw.com.au/

no sparks, and you can cut through sheet metal no problems. Not a gimmic, all roof sheet guys use them.

The glasswool is not as scary as it sounds. It has no asbestos, and doesn't make you itch like a bastard unless you roll in it. Wear a long sleeve shirt and take it out slowly.

[Sir Stinkalot]

We also have an old gravity hws in the ceiling. I plan on purchasing a small pump and pumping the grey water from the washing machine and shower up into the tank where it would then act as a gravity fed distribution into the garden. The tank wouldn't be storing the water for long however it is a convenient way of collecting the large volumes that the washing machine produces over a short period of time.

If you have the space just push it to the side and make some use of it.

[China]

Sir Stinkalot have a very good look at your old hws befor you pump it full of water, they are usualy replaced because the have developed a leak in the tank

[Sir Stinkalot]

Sir Stinkalot have a very good look at your old hws befor you pump it full of water, they are usualy replaced because the have developed a leak in the tank

Good point China .... there are a few things to check first ....

1. If it leaks.
2. How to get the water up to it.
3. How to get a tap into the side to get the water out.

[Jacksin]

As Skot says it is easy and didn't take long.
The inner copper cylinder I cut up with snips and dropped through the manhole. It took longer to clean up the mess and cart it all outside than dis-assemble the HWS.

[redcharger]

I just removed mine(the electric HWS) I used a combination of cold chisel and tin snips. I smashed off the pop rivets holding the top on..removed it folded it in half so it fitted out the manhole, then cut down the side using the cold chisel and mash hammer removed the outer center section after detaching it from the bottom section pop rivets again then folded it up. The copper section I cut in half and folded it up so it fitted out the manhole.

Make sure the POWER is disconnected (I put my electrician hat on) and the water too.

Also make sure you collect all the copper bits and go to the scrap metal man mine worked out to $140 which was a nice little bonus.
Mike

[Bodgy]

Just empty it and leave it there.

Do you need the space for something else?

Ours has sit there, happily, for ten years.

I'm waiting for the price of copper to max up.

[zacnelson]

Last week I finally got around to removing the hot water tank, it was pretty easy actually. I got $56 for the copper which made it worthwhile! I needed to remove it anyway because it was right in the way of a future load-bearing beam.

[peterw]

G'day Fella's
Seems a bit too much fun to bust up a HWS in the ceiling.
Many have been replaced over the years and is done by cutting out some tile battens and one rafter to make a hole big enough. If you have a close look above and around the tank, you are likely to find where it has been nailed back together.
Remove tiles, knock the timbers apart, lift the (empty) HWS onto the roof, if desired, watch it smash it to pieces as it hits the garden below, and nail the rafters back together replacing the tiles. The empty HWS weights about 30-35 kg.