New system. Noisy taps.

[SimonG]

No problem Dave.

 

[DRM46]

Hi again. Had my old plumber cast his twigger over things and he said all that’s visible is ok apart from some missing and unclipped clips.

Had the pressure checked and it just over 6 bar. A PRV is to be fitted to see if it helps.

Boiler is now on and heating is very quiet and responsive. Nice hot water from taps except the bath tap which is not hot enough to have a hot bath, only a warm one. Shower is the same and not great on flow as no cold water can be mixed with it.

Installer said that’s to be expected and comes with having a combi.

I’d like to ask you fellas in the know if this is acceptable?

I’m not exactly happy at the prospect of no hot showers or baths and the bath taking over 10 minutes to fill. The wife and girls even less amused.

Thanks in advance for any replies.

 

[Gasmk1]

you should get hot water same at all the taps so there may be a problem of some mixing going on may need some more investigating

 

[Riley]

If you reduce the flow does the water get hotter

 

[Scott_D]

If it’s 20 litres from the hot tap it will only be warm, the boiler will produce around 10 lpm hot.

It all sounds like six of one, half a dozen of the other with both of you.
If someone asks will this tap work, all you can do is look at the info available and say yes or no.
I would always say get a known brand tap/shower

 

[DRM46]

Riley, yes it gets hotter at a reduced flow. Fully open is warm at 10 litres minute, if I reduce it to 5 litres it gets hot. That’s quarter of an hour to run a bath, though.

Also, if the bath hot tap is on all other hot taps reduce to a dribble. Again, the installer tells me this is normal.

Scott D, Hudson Reed taps. Not the best but no problems with them in the past.

Gasmk1, thanks, it’s good to have it confirmed that this isn’t right. Problem is it’s me doing the investigating and I know very little.

 

[Chuck]

Riley, yes it gets hotter at a reduced flow. Fully open is warm at 10 litres minute, if I reduce it to 5 litres it gets hot. That’s quarter of an hour to run a bath, though.

If the water is coming in at 10°C and you want your bath to be at 40°C that's a temperature rise of 30°C. For 10 litres per minute this requires 21 kW delivered to the water. Assuming your bath is a typical 70 litre a 30kW boiler should be able to fill it in around 5 minutes.

So, based on your description, it seems to me that your boiler is only transferring about 10kW to your hot water. This is a third what it should be able to manage, a discrepancy that is big enough to merit investigation by a Gas Safe Registered heating engineer.

 

[Riley]

Have you measured 10lpm?
Mains coming in at this time of year is

Riley, yes it gets hotter at a reduced flow. Fully open is warm at 10 litres minute, if I reduce it to 5 litres it gets hot. That’s quarter of an hour to run a bath, though.

Also, if the bath hot tap is on all other hot taps reduce to a dribble. Again, the installer tells me this is normal.

Scott D, Hudson Reed taps. Not the best but no problems with them in the past.

Gasmk1, thanks, it’s good to have it confirmed that this isn’t right. Problem is it’s me doing the investigating and I know very little.

have you measured 10lpm and 5lpm?? Only ask as if the incoming mains is colder this time of year then you’ll get less temp rise at full flow. Yes combi trait

 

[DRM46]

Thanks Chuck and Riley. Yes, I measured with a 13 litre bucket. 80 seconds to fill with tap fully open. Two and a half minutes with it open enough to get hot water.

Right, I see, so regardless of what temperature the hot water is set to, a combi is not necessarily going to reach that temperature. I’m learning some things here that I wish where explained at the consultation stage. I was sold on “mains pressure instant hot water and no need for a power shower”, instead I’m looking at something slower and cooler than the system that was took out but with better central heating.

Chuck, thanks. Next time I use a plumber I’m going to check he can give me numbers like you just did and be as helpful as Riley. A gas safe engineer is going to look at it. I’ve also learnt that this installer is not gas safe, as I was originally told, and he needs to get someone else in to commission it. I’m going to ensure I’m there when it happens to ask questions.

 

[Riley]

Then he has no argument re your previous message regarding siting of the boiler. BIN them then report them it is illegal to commission someone else’s work. If the boiler has not been commissioned why is it even on

 

[Riley]

I would also add that this adds weight to your claiming back your additional costs based on the fact the guy is clearly not qualified

 

[Chuck]

Right, I see, so regardless of what temperature the hot water is set to, a combi is not necessarily going to reach that temperature.

I think that once your combi is commissioned properly and delivering its specified 30kW rather the puny 10kW it is currently delivering you'll be happy with it. As long, that is, as you aren't trying to fill two baths in different rooms at the same time, which I don't think you are planning.

 

[Scott_D]

I think some pictures are needed

 

[Riley]

Would be good to see the install but I’d be phoning the plumbers boss and laying out your findings followed by an email so you have a record is probably the way to go