Tuesday, 11 November 2008

[Progress.142] Water tank filter bag cleaned, and new discovery

Spent some time with the water tank the other day, trying to solve the mystery of water overflowing from the rain water tank whenever it rains. You will be surprised with what I found...

This is what the top of water tank looks like, just have to remove a few screws to remove the black leave strainer and open it...

With the leave strainer removed, I was quite surprised to see lots of water and green stuff (algae?) inside. So may be the builder was right, the filter bag was blocked, needs cleaning, and the water couldn't pass through the filter bag?

But wait, hang on, with the filter bag half-removed, the water level in the tank was almost full. How come there's so much water in the tank? It hasn't rained for a few days, and we must have used the washing machines a few times, flushed the toilets many times everyday, and also watered the lawn yesterday as well. Does the pump automatically refill the tank to the "full" level? Will look into this later.

I slowly pull the bag out, to me it looks like a huge, dirty underwear :-) ....

I left it on the floor and you can see how dirty it is. Time for some cleaning...

Sorry if it's a bit unclear as I was using the camera on my mobile. There's this small logo which says "TANKSNAKE". Later I did a quick search on Google and found this company in QLD with a simple single page web site. Their web site also provides a few tips about how to look after your filter bag, you might want to have a look to learn some info about that. I think the tip of adding a cover to block the sun light is quite helpful.

While cleaning it, from inside the bag, I found this part at the bottom which is in different colour and feel like plastic. Don't know what is it, hope it's not a patch to fix/block the hole...

This is what that plastic thing looks from the outside of the filter bag.

Any way after about 15 min rubbing, brushing and cleaning, it looks much cleaner now. To be honest I still don't think this is the root cause of the overflowing water issue.

The Bureau of Meteorology said it's going to rain starting from this Friday and will last for a few days. So I am going to leave this filter bag out of the tank just for this week and see if the water still overflows. If that's the case, our builder will have no more excuse!

Now that I fixed the dirty filter bag, let's get back to the "full tank of water" problem I mentioned above. I decided to do a simple test:

  • First, make sure no one in the house is using the toilet/washing machine/front external hose

  • I asked the kid to flush the toilet a few times while I stood next to the water tank control box - I could hear the pump running when the toilet is refilling water, and I could also feel some vibration on the pipes connecting the water tank to the pump, but I couldn't tell whether the water was coming from the tank or the mains

  • I repeated the test above, but this time I stood right next to the water meter at the front of the house - the meter starts running whenever the toilet was refilling water, this can't be right! I though it should be refilling from the water tank?

Based on above I have this bad feeling that, may be since the water tank was installed in February 2008, hand-over in April, and we moved in around late May 2008, the whole water tank system has never worked??!! Not an expert on this, but also have feeling that this might also explains those green algae thing if the water was left untouched for a few months in the tank... We will definitely ask the builder to come and have a look.

As a final proof/test, I decided to try something else. As shown below, there's garden hose at the front of the house, next to the garage, clearly marked with "rain water" sign. This time, instead of flushing the toilet, I am going to use this hose to test the water meter.

After making sure no one in the house is using water, I took this short video. You can clearly see the water meter starts running whenever the hose is on. Just look at the little red arrow at the left hand side.

Please note that I have tried also turning on/off the power switch on the water tank pump and that doesn't make any difference. When it's off, it just gets water directly from the mains and when it's on, as mentioned above, I could hear the pump working, but couldn't prove whether it gets the water from the tank or the mains. And looking at the water meter is the only way I can think of to prove that it's using the water from the mains!

Need some opinions from everyone. Do you think my test plus the full tank of water (after a few non-raining days) are sufficient to prove that our water tank system is not functioning? Or can you think of anything else I can test?

Will keep everyone posted if I hear anything from the builder...


Anonymous said...

I'm assuming that the idea is to use water from the tank to fill up the toilets and via the hose and if the tank is empty switch over to the mains supply. If you're thinkin it's just getting water from the mains, then what happens when you turn off the mains water supply? Do you still get you toilets filling up? Is there still water coming out of the hose then?

Allan said...

Thanks for the comment. I already tried turning off the mains before during the hand over inspection.

What we found is, if the mains been turned off, the whole water tank system stops working. The pump won't work after that, therefore no filling up for toilet or the hose.

May be it's because it relies on the water pressure from the mains to function properly.