Hot Water Flow In Kitchen Sink.

[Tilly2]

Has anyone any idea as to why the hot water tap in the kitchen is so pathetic? We did have a Homeserve plumber have a look at it and he said it was probably an air lock but didn't do anything about it. The rest of the taps in the house are fine and the cold water, from the same dual swan neck tap, comes out fine. When we switch from cold to hot, the pressure is minimal and it takes ages to fill a bowl with hot water in the kitchen sink.

[Togo]

Is the hot from a gravity fed hot water tank or direct through an in line boiler?

[Tilly2]

Oh Togo! I don't know the answer to that. We have a gas boiler in the kitchen is all I know.

[Tilly2]

...and a hot water cylinder in the airing cupboard.

[Togo]

I see that you said that the other taps are OK Tills. In which case I would firstly be checking the pipework to that tap, look for kinks etc if there are any of the flexi armoured sections(particularly right next to the tap) Look for any inline isolating valves and whether they are on fully. Is the tap an older fitting that could have a problem with the hot valve or ceramic disc?

[Togo]

If you have a hot tank Tills it is probably gravity fed( the weight of water in the tank determines the pressure) That being the case the pipe work could have a partial blockage reducing the flow, or as I have said the tap is itself goosed. Visual inspections from tank out to tap is the first step.

[Atheist]

If it's a kitchen mixer tap and the cold is OK, then there could be a kink in the hot flexi pipe (see Togo), or a part-closed valve. Might be interesting to disconnect the hot water pipe from the tap to see if there is good flow from the pipe before it enters the mixer. I would think that any decent plumber could sort this out.

[Old_Geezer]

If it was an air lock surely he'd have fixed it ? Maybe try someone other than Homeserve next year.

A flow issue. Probably not enough height. Do you have a tank in the attic ? Consider adding a pump to help the flow along.

[Togo]

If you have an inline boiler(hot water goes straight to tap without a tank) you will hear the boiler spark up when you turn on the hot tap. Instantly. If you have a tank the boiler will not spark up until the tank has replaced what you have taken out with cold water, and will also need to be told to by the timer or control panel.

[Tilly2]

I think the tap is ok Togo as the cold water flows well through it. I'll have a look at the tank and pipes flowing from it to see if there's anything amiss. I am going to call Homeserve again and insist that they check the feed from the tank to the kitchen. Thanks for you help. Much appreciated.

[Tilly2]

OG, he didn't fix it! easy money for him I suspect. Next time, I won't be fobbed off.

[Togo]

On some taps Tills the hot and cold flow have separate valves. One can fail whilst the other stays good. Hot water through a valve could damage it quicker( a lot depends on the type of tap)

[Tilly2]

Should I insist that they inspect the valves on the tap itself?

[Togo]

If you are having trouble showering Tills I will volunteer to help out with a watering can. (^_*)

P.S Hope you are feeling well otherwise. Had you jab?

[Togo]

Yes Tills if it comes to that. I would, initially, be looking at the pipework from tank or boiler to tap. If there are any valves or any old iron bends or fittings then they would be no 1 suspect. Ta for BA.I will cherish it. :))

[TonyV]

Tilly the flow of hot water should be better downstairs if gravity fed. I suspect problem is with tap itself, without knowing whether it has ceramic or rubber seals, I think problem lies there, probably something sticking inside the tap, only way to know is to take tap apart.

[pastafreak]

I've had a similar problem with my kitchen tap for years. Turn it on, boiler kicks in, water starts ok, then becomes a dribble. I turn it up a bit more...that might be enough but often it isn't. Sometimes shower is similar. I've wondered if it was a way to control hot water usage.
I'm on upper 2 floors of 4 floor building.

[jennyjoan]

Tilly I'm exactly the same when I got a new kitchen about 2 or 3 years ago I got a lovely deep sink which I love with mixer taps, cold water brilliant flush but hot tap like more than a dribble.

I did get my Handyman who is very good - he took the dishwasher out to get a good look at the back or underneath the taps but couldn't find anything wrong. I've learnt to live with that. Can't be doing with unnecessary workmen in my house now.

[jennyjoan]

I'm looking at Pasta's post re the shower - no my shower works brilliantly - if I had problem with the shower then I would let my plumber in. Yes my nephew is a plumber but he is still a workman LOL

[Tilly2]

Thank you all for your answers. I am now armed with a bit more information for when Homeserve arrive on Friday.

P.S. Togo, the shower's fine but thanks for the offer. :-)
...and yes, I have had my jab and feel a lot better for having done so.

[The Builder]

I've had a go at similar questions before, Tilly. I can't find it though.
Nevertheless...
Possibly...

The mixer tap is NOT suitable for "low pressure" systems
(cold water will always belt out easily because of mains pressure. Hot pressure is relatively feeble because it's only gravity.)
Look for the isolating valves Togo mentioned. Their "bore" is far too small for gravity systems.
Are braided steel connectors used to connect to the underneath of the tap?
They are also too small.

If you are in a 2-storey house with the cold tank in the roof, that is enough "gravity", but only if the flow is not being restricted.

This problem doesn't arise with a Combi boiler because it uses mains pressure.
Combined mixer taps are a real problem with gravity systems.