# Forum Home Renovation Plumbing  Is There A Special Tap For Rainwater Tanks?

## Metal Head

Hi, 
The brass external tap I had fitted to my rainwater tank doesn't usually work without a bit of TLC. I have tried 3 types of washers :Redface:  
1) A brass body with a "O" ring recessed into it
2) A normal plastic washer with the rubber seal attached to it
3) A brass body with a half conical shaped rubber bung attached to it. 
On each occassion the water flow would get less and less until it wouldn't come out :Shock: . I only close the tap as much as I needed to (on each occassion) so although I thought I wasn't overtightening it I may have unknowingly. 
So my feeling is that the pressure (atmospheric) is not sufficient to force the washer off it's seating :Frown: . 
Has anyone else had a similiar problem and if so how did you fix it - maybe with a special type of tap?. 
Cheers
David

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## echnidna

we had that problem a lot with normal taps. Found that fitting 3/4" taps overcame the problems.

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## Barry_White

> we had that problem a lot with normal taps. Found that fitting 3/4" taps overcame the problems.

  That's interesting Bob, I have a 1/2" tap over the dogs bowl the only 1/2" tap on the property and I have to belt the crap out of it to make it run. I put it down to a soft washer that is sticking to the seat and was going to change it to a hard washer. 
Maybe what I should do is change the tap.

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## ozwinner

> and I have to belt the crap out of it to make it run.

  Poor bloody dog.. :Frown:  :Cry:  
Al  :Biggrin:

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## Big Shed

I use metal ball valves with nylon seats for that reason. They always work, no matter how low the pressure.

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## Barry_White

> Poor bloody dog.. 
> Al

  I can see I'll have to choose my words more carefully Al

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## ozwinner

> I can see I'll have to choose my words more carefully Al

  
Just funnin Baz, just funnin.. 
Al  :Biggrin:

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## watson

Ditto on the ball valves.
Our whole place runs on them except the bathroom and the kitchen......asthetics I guess.
Regards,
Noel

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## KevM

Only two types of valves to use because of the low pressure and both are solid brass bodies. 
The first rotates the hole in a cylinder in line with the flow (can't remember the name), the second raises and lowers a block of brass to allow the water flow (gate valve).

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## olddog

If using house taps on a tank,give the washer shaft a tap with a hammer so as to make it a real tight fit in the tap spindle so when the tap is turned on the washer lifts off the seat by the action of the spindle rising all the old timers used the method because you could get house taps cheap second hand but not tank taps............Peter

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## Harry72

> The first rotates the hole in a cylinder in line with the flow (can't remember the name)

  Yep that'll be the ball valve type.

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## Metal Head

> If using house taps on a tank,give the washer shaft a tap with a hammer so as to make it a real tight fit in the tap spindle so when the tap is turned on the washer lifts off the seat by the action of the spindle rising all the old timers used the method because you could get house taps cheap second hand but not tank taps............Peter

  Hi Peter, 
Are you saying that you would hit the handle (as indicated by the arrow in the image attached)?. If so, unfortunately is isn't much use in my application, as the tank and the fitting that attaches the brass tap to it are plastic. So unless one supported it, it would just snap off and I would be in more strife than Ned Kelly :Redface: . 
Cheers
David

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## Metal Head

Thanks lads (too many to mention) for all your replies - much appreciated.  
The idea of using a ball valve I thing will be the way to go - attached in one presently for sale on EBay (see attachment) for $25 including postage. However, as I am going to Bunnings tomorrow to get other items for it - clear plastic tube to monitor the water level of the tank (as asked in a previous thread of mine) - I will get one there. 
Cheers
David

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## Barry_White

> Hi Peter, 
> Are you saying that you would hit the handle (as indicated by the arrow in the image attached)?. If so, unfortunately is isn't much use in my application, as the tank and the fitting that attaches the brass tap to it are plastic. So unless one supported it, it would just snap off and I would be in more strife than Ned Kelly. 
> Cheers
> David

  No what he is saying take the washer out and hit the top of the little shaft on the top to burr it over so it is a tight fit in the hole in the spindle of the tap. 
The only problem is if it is a nylon washer this may not work so you would need to replace the washer with a brass one.

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## journeyman Mick

David,
Normal taps rely on the water pressure to lift the washer off the seat, there's not enough water pressure in most tanls to do this reliably. Therefore, like others have said you need to use a ball valve, gate valve (not too popular nowadays), butterfly valve or water tank tap. Water tank taps use a tapered shaft with a hole through it (a bit like a morse taper) rather than a ball with a hole through it like a ball valve does. Water tank taps usually have a locking hasp on them too, so that you can lock your precious water up and stop some wally from leaving the tap on and draining it all out accidentally. You can motherfy a normal tap to make it work at low pressures but I don't think it's worth the mucking around. 
Mick

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## abitfishy

I needed to replace a garden tap that wouldn't turn off (great at 7pm, luckily bunnings is open late!).  Anyway, they have a new type of tap that looks like a normal tap, but it has a lever on the top that just turns a quarter turn from completely stopped to get full water pressure.  Not sure if these would help your problem.  They are different internally as you can see the 'semi circle' inside turn as you turn the lever.  I think it is a fantastic tap...

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## journeyman Mick

That sounds like a quarter turn ceramic disc tap. These would probably work with low pressure but don't like any particles in the water which may scratch the ceramic discs. 
Mick

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## bricks

get a ball valve, they will cost you $5 - 8 bucks at bunnings,

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