New quooker reducing the flow of the hot water

silvercar

grumbler said:

silvercar said:

I was just puzzled as to why this hot tap was slower than the utility room hot tap, when they both get their feed from the same route. It seems adding the quooker has slowed the hot tap down and I don’t know why.

Do you mean replacing (the old tap(s) with quooker), not adding? A big difference...

In the old kitchen we didn’t have a quooker, the hot water feed to the kitchen sink was adequate. Now we have a kitchen sink with one tap that has cold mains water, hot water from the HWT heated by the boiler and the boiling water from the Quooker. It is only the hot water from the HWT that has a slow flow.

FreeBear

ThisIsWeird said:

This is the baby: https://www.toolstation.com/grundfos-upa-15-90n-home-booster-pump/p71846

https://www.bes.co.uk/in-line-automatic-shower-power-booster-sp2b-22904/ - Half the price and quite a bit smaller. I have plans to fit one on my cold water feed once the old incoming pipe has been replaced.

Primeh

If you install a tap that requires a pressurised water system and your system is non-pressurised (gravity fed), you will have an extremely weak flow of hot water; sometimes the flow is too weak to enable the tap to supply water at all.

Homes that have a low-pressure water system require specific low-pressure kitchen mixer taps that are designed to operate under lower pressures, ensuring a steady flow of water.

Alternatively, homes that have a high-pressure water system are generally able to use any kitchen tap and will still have a steady flow of water.

The reason the boiling water is ok is that the tank works on cold pressure coming in, much like an unvented system. The reason the cold is ok is because its almost certainly mains pressure coming in. The reason the hot is no good is that the quooker requires 2bar and you don't have the drop from the tank to get you that.

The reason the utility tap probably works is that it's a low pressure tap already? Have you changed that yourself or was that always there?

grumbler

silvercar said:

I want the 3 in 1 quooker, so a separate tap isn’t the answer.

silvercar said:

grumbler said:

silvercar said:

I was just puzzled as to why this hot tap was slower than the utility room hot tap, when they both get their feed from the same route. It seems adding the quooker has slowed the hot tap down and I don’t know why.

Do you mean replacing (the old tap(s) with quooker), not adding? A big difference...

Now we have a kitchen sink with one tap that has cold mains water, hot water from the HWT heated by the boiler and the boiling water from the Quooker. It is only the hot water from the HWT that has a slow flow.

Now I'm confused - what's 'Quooker'? Is it not a "tap that does it all"?

If it's 'three [stuffed] in one', then it's hardly a surprise that the flow of low pressure water is slow (because of small cross-sections of all passages inside)

Primeh

You can buy a quooker that is just a boiling water tap , there are lots of varieties, the most popular is the hot cold boiling ones, I've fitted some with cold filtered, cold sparkling and now you can get a scale reducer to go through too!

ThisIsWeird

silvercar said:

ThisIsWeird said:

silvercar said:

Thanks all.
yes, it would be vented as we do have CWS in the loft. Ok, that explains it.

I was just puzzled as to why this hot tap was slower than the utility room hot tap, when they both get their feed from the same route. It seems adding the quooker has slowed the hot tap down and I don’t know why. Because the Quooker its designed for high pressure systems, as I explained.

I want the 3 in 1 quooker, so a separate tap isn’t the answer. Cool - that narrows down the options to one. A pump may be the answer, almost certainly is... but it may be something we live with, especially as we can get a mix of boiling water from the quooker and cold water into the sink, rather than use the hot water feed. WOW! :-)

Replies in bold.

This 'Quooker' cost you how much? I'm guessing around onethousandpounds? And you love it so much that you are prepared to live with a defunct hot water supply, a supply that's already been heated and is sitting pointlessly in a hot tank, begging to be used, but - pah! - it just ain't coming out fast enough?

So, you'll spend how long blending the pitiful flow of boiling water from your Quook, heated by probably the most expensive form of domestic energy available, instead of installing a ~£100-odd pump that'll cost zilch to run, and will transform your whole domestic HW supply to all your taps?

Yeah, fair enough.

ON PLANET ZORG! :-)

Yes, about £1k, but it’s sunk money as it’s spent and part of the kitchen refurb. The flow of boiling water from the quooker is good.

Now I’m confused, it is the hot water to this kitchen tap that is slower than other hot water taps in the house that I’m trying to understand, not the hot water feed in general. 

Did you read my bits on bold? I believe all your answers are there.
It's your call, but if for the sake of a £100-200 pump - which will almost certainly transform the hot water supply from your boiler to all your taps - you are instead going to compromise by using a Quook to fill your sink, well...

ThisIsWeird

FreeBear said:

ThisIsWeird said:

This is the baby: https://www.toolstation.com/grundfos-upa-15-90n-home-booster-pump/p71846

https://www.bes.co.uk/in-line-automatic-shower-power-booster-sp2b-22904/ - Half the price and quite a bit smaller. I have plans to fit one on my cold water feed once the old incoming pipe has been replaced.

£120 for that nasty little whirry thing? Pfffft.

Jonboy_1984

We lived in a ground floor flat. The cold water tank was directly above the hot water tank (so hw was sat in ground and Cw was around 4' off the ground.

Hot water pressure was pitiful and when I accidentally bought a normal pressure mixer tap for the kitchen it would barely dribble hot water. Got a low pressure tap and it was much better but still poor compare to many other properties. 

silvercar

grumbler said:

silvercar said:

I want the 3 in 1 quooker, so a separate tap isn’t the answer.

silvercar said:

grumbler said:

silvercar said:

I was just puzzled as to why this hot tap was slower than the utility room hot tap, when they both get their feed from the same route. It seems adding the quooker has slowed the hot tap down and I don’t know why.

Do you mean replacing (the old tap(s) with quooker), not adding? A big difference...

Now we have a kitchen sink with one tap that has cold mains water, hot water from the HWT heated by the boiler and the boiling water from the Quooker. It is only the hot water from the HWT that has a slow flow.

Now I'm confused - what's 'Quooker'? Is it not a "tap that does it all"?

If it's 'three [stuffed] in one', then it's hardly a surprise that the flow of low pressure water is slow (because of small cross-sections of all passages inside)

I’m not explaining it well. All the water comes out of the quooker tap - through this one tap, the cold is mains fed and powerful, the boiling is reasonably powerful, it’s just the hot that comes from the tank that is weak. 

As for the other taps around the house, they are all ok. So the only one that has an issue is the hot water that is coming through the quooker tap, but is delivered from the HWT. So any question of fitting a pump would be to benefit this one tap, as the others don’t need it. 

(It would also bring questions of where to position it, there is no room and no plug point in the cupboard housing the tank. But that is secondary).

I just wanted some reassurance that the plumber is correct in explaining away the low pressure and there isn’t something else that the plumber has glossed over.

grumbler

silvercar said:

grumbler said:

silvercar said:

I want the 3 in 1 quooker, so a separate tap isn’t the answer.

silvercar said:

grumbler said:

silvercar said:

I was just puzzled as to why this hot tap was slower than the utility room hot tap, when they both get their feed from the same route. It seems adding the quooker has slowed the hot tap down and I don’t know why.

Do you mean replacing (the old tap(s) with quooker), not adding? A big difference...

Now we have a kitchen sink with one tap that has cold mains water, hot water from the HWT heated by the boiler and the boiling water from the Quooker. It is only the hot water from the HWT that has a slow flow.

Now I'm confused - what's 'Quooker'? Is it not a "tap that does it all"?

If it's 'three [stuffed] in one', then it's hardly a surprise that the flow of low pressure water is slow (because of small cross-sections of all passages inside)

(It would also bring questions of where to position it, there is no room and no plug point in the cupboard housing the tank. But that is secondary).

Is there really no electrical immersion heater in the cylinder? Luck of a 'plug point' doesn't mean that it's hard to create it.

Not that I'm a big fun of pumps.

I just wanted some reassurance that the plumber is correct in explaining away the low pressure and there isn’t something else that the plumber has glossed over.

"because the quooker is on that tap", if that's really what the plumber said, is incorrect. 

The correct answer is "because low-pressure hot water was connected to a normal tap, but now is connected to quooker tap that is unfit for low-pressure water supply".