FarmI wrote:

Yes. Looking for ideas on refill times and how far above the top of the
toilet cistern I need to place the mains top up float valve.

??? You asked about filling the cistern from your tank.

Correct, but when the tank level gets too low, I'll need to add water to
the tank to keep the toilet flushing until the tank it is topped up with
the next rain.

Having the mains top up float as low as possible means that I use as
little as possible mains water.

Do not confuse it with my greywater discussions.

Sydney Water has a campaign for people to connect their rainwater tanks
to their toilets, but they want you to buy and install an electric water
pressure pump to do this. Under their plan, you still have a mains top
up float value for when the tank gets low.

While I am happy to consider this, I realise that the cost of
electricty, pump, etc is far more than I will ever save in reduced mains
water cost, so forget it.

So I am looking at gravity feed version. It just means there is less of
the tank available and the mains top off float valve is installed higher.

In practice, unless we had a run of dry weather, the tap for the mains
top off would only be turned on when needed.

What I am trying to avoid is finding that 1' above cistern head allows
for one flush a day by the time it reflls.

If someone comes back and says that you really need 3', then it is a no
goer as not worth the effort with the existing tanks, unless I somehow
hit upon a very cheap supply of tall, thin water tanks that will fit up
the side path. (which has lost is effectiveness as a second side path
when the new "better insulated" water heater had to go outside).

On Mon, 18 Feb 2008 18:17:06 +1100, Terryc
wrote in aus.gardens:


While I am happy to consider this, I realise that the cost of
electricty, pump, etc is far more than I will ever save in reduced mains
water cost, so forget it.

With mains water at about $1 per kiloliitre you will NEVER save money
on your water bill by putting in a tank water system of any
description pump or no pump.

Lets face it we are using something like a $1000 tank to store $5
worth of water it makes no sense economically for any city dweller.
You have to do it because you think it is the right thing to do and
with an eye to the future.

Anyway a reasonable pump with an auto cutout can be bought for between
$160 and $250 so it doesn't add that much to the total cost. and the
electricity it uses to fill your toilet over a day is probably less
than your TV.


Regards
Harold

Tantum religio potuit suadere malorum - Lucretius

Dinsdale Pirana wrote:

You have to do it because you think it is the right thing to do and
with an eye to the future.

Well, actually, it means I can water my veges whenever they need it.

Anyway a reasonable pump with an auto cutout can be bought for between
$160 and $250 so it doesn't add that much to the total cost. and the
electricity it uses to fill your toilet over a day is probably less
than your TV.

You are forgetting all the other costs involved in setup, like plumber
and electrician, especially f you want the piddling rebate.

I am also suspiscious about the cheap pressure pumps around and their
longevity (sp?).

"Terryc" wrote in message
FarmI wrote:

Yes. Looking for ideas on refill times and how far above the top of the
toilet cistern I need to place the mains top up float valve.

??? You asked about filling the cistern from your tank.

Correct, but when the tank level gets too low, I'll need to add water to
the tank to keep the toilet flushing until the tank it is topped up with
the next rain.

Having the mains top up float as low as possible means that I use as
little as possible mains water.

Do not confuse it with my greywater discussions.

I wasn't. I was responding directly and only to your water tank question.

So I am looking at gravity feed version. It just means there is less of
the tank available and the mains top off float valve is installed higher.

In practice, unless we had a run of dry weather, the tap for the mains top
off would only be turned on when needed.

What I am trying to avoid is finding that 1' above cistern head allows for
one flush a day by the time it reflls.

???? The time to refill will depend on the size off the pipe. As I wrote
earlier, if you use a quarter inch drip line it would take a long time. If
you use a half or one inch pipe it will take minutes.

The bigger concern for only 1' of water above the cistern would be the size
of your water tank. If you have one of those minute tanks that seem to be
popular in the city then only 1' of water will mean tuening on the mains
again pdq. If you have a 2,000 gall tank then 1' of water will flush for a
long time.

If someone comes back and says that you really need 3', then it is a no
goer as not worth the effort with the existing tanks, unless I somehow hit
upon a very cheap supply of tall, thin water tanks that will fit up the
side path. (which has lost is effectiveness as a second side path when the
new "better insulated" water heater had to go outside).

As I explained earlier, you only need the level of the water in your tank to
be above the inlet to your cistern. That is why I wrote about how farmers
use the plastic pipe to move water from the irrigation channel which is only
a few inches higher into their paddocks.

Water will always flow to a lower level and try to equalise it's level.
Just think of this as a very simple but effective devise used to build - a
hose with water and 2 clear plastic ends added to the tube - the water in
each clear plastic end gives a level that is true and accurate.

FarmI wrote:

???? The time to refill will depend on the size off the pipe. As I wrote
earlier, if you use a quarter inch drip line it would take a long time. If
you use a half or one inch pipe it will take minutes.

Okay, I was thinking about retaining the existing inlet regulator, which
is 1/2" pipe and designed for mains pressure.

What I think I might do is look at just putting in a trough float arm.
This was effectively what the original toilet had until it wore out and
was replaced by this self contained device.

So, if I can fit a simple trough float arm in there as well, I could
just run a parrallel pipe from the tank at ground level. So, when the
tank water level drops too low, then I just turn the mains tap back on.

Shouldn't be a problem with the newer plastic walled cistern, but might
have to come through the bottom on the older ceramic cistern.

Problem solved.

We have 1,000 & 5,000 litre tanks atm.

"Terryc" wrote in message
FarmI wrote:

???? The time to refill will depend on the size off the pipe. As I
wrote earlier, if you use a quarter inch drip line it would take a long
time. If you use a half or one inch pipe it will take minutes.

Okay, I was thinking about retaining the existing inlet regulator, which
is 1/2" pipe and designed for mains pressure.

What I think I might do is look at just putting in a trough float arm.
This was effectively what the original toilet had until it wore out and
was replaced by this self contained device.

So, if I can fit a simple trough float arm in there as well, I could just
run a parrallel pipe from the tank at ground level. So, when the tank
water level drops too low, then I just turn the mains tap back on.

Shouldn't be a problem with the newer plastic walled cistern, but might
have to come through the bottom on the older ceramic cistern.

Problem solved.

We have 1,000 & 5,000 litre tanks atm.

Yep. That sounds good. It starts simple and you can escalate or reverse it
easily if you really need to do so. I suspect you won't have to.