Flow rate to bathroom

[jez9999]

Hi all,

Over the past couple of weeks I've been having my bathroom totally renovated. Today or tomorrow is the last day the plumber/DIY man will be here, he'll have finished by then.

Mostly I'm pleased, but the flow rate of the water coming out of the bath and basin taps is, frankly, pathetic. It can take half an hour to fill up the bath; it's the worst hot flow rate I've ever seen.

Also, I switched from my old small electric shower to a mixer shower during the renovation, specifically because I was told that was my best chance of getting a powerful shower with a combi-boiler setup (I like powerful showers!) The pressure is just about OK, though barely any better than the small electric shower before. My mains pressure is OK, certainly high enough that it ought to give me a more powerful shower... any ideas why it might be so weak? I'm having trouble getting answers out of the plumber, all he seems to say is 'you won't get the same hot water pressure as cold'. No, but surely you can increase the hot water pressure with a more powerful boiler! Or, maybe there is something wrong with my boiler that's weakening the hot water pressure? It's a Ferolli boiler. Any help would be appreciated, thanks!

 

[tripty]

Hi,

With a combi you need to have good mains pressure *and* flow rate, you then need a big boiler that can raise so many litres/minute by such and such a temperature.

What is the exact model of your Ferolli?

Measure your flow rate at your kitchen tap with a bucket and stopwatch - how full (in litres) is the bucket after 30s then double that to get your approx flow rate.

Hope that helps.

 

[jez9999]

Hi,

With a combi you need to have good mains pressure *and* flow rate, you then need a big boiler that can raise so many litres/minute by such and such a temperature.

What is the exact model of your Ferolli?

Measure your flow rate at your kitchen tap with a bucket and stopwatch - how full (in litres) is the bucket after 30s then double that to get your approx flow rate.

Hope that helps.

Hi,

The boiler's a Ferroli Modena 80 E. I tried filling a bucket with the cold kitchen sink tap for 30 seconds - there was about 10 litres of water. It seems the mains pressure and flow isn't that bad.

Probably the boiler that causes the slow hot water flow. We did today remove both a flow restrictor and a filter, that were in two of the boiler's pipes (miniscule holes in both of them, it's amazing the water got through at all!), and the flow is a little better now. I'm guessing it's as good as I'm gonna get out of this boiler.

For some reason, though, the plumber didn't seem to accept that just buying a bigger, more powerful combi boiler, would help me. It seems to me that the mains is more powerful than the hot water flow coming out of the boiler, so presumably a bigger more powerful boiler would give me a really powerful shower?

 

[tripty]

Yep, seems your mains is up to it! So, a bigger combi would give you a better shower - as long as nobody else runs a tap and you shower head isn't huge.

Changing the boiler will be pricey though

Hope that helps.

 

[Agile]

Pressure and flow can be related in some situations but both seem to be very badly misunderstood even though the concepts are well within the GCSE syllabus.

Even many people working as plumbers cannot explain flow and pressure to their customers.

Tony

 

[dextrous]

Pressure and flow can be related in some situations but both seem to be very badly misunderstood even though the concepts are well within the GCSE syllabus.

Not sure it is - I'll check tomorrow

 

[tripty]

Pressure and flow can be related in some situations but both seem to be very badly misunderstood even though the concepts are well within the GCSE syllabus.

Not sure it is - I'll check tomorrow

No, I don't believe they are, although it may be on GCSE level qualifications such as btecs, gnvqs. I don't remember anything related to thermodynamics until A-Level. Same goes for fluid dynamics.

 

[Agile]

At a school presentation tonight the science teacher told parents that as they would not understand the subect all they could do was ensure the child spent time revising rather than facebook!

The English lit teacher was more enthusiastic and gave the parents a poem to analyse and underline different aspects in different colours. many parents seemed to be colouring the same parts too.

The maths teacher was running through a simple looking problem involving two football teams with six reserves. The answer was 112/55 !

I could not see the relevance of big fractions when they have no relevance to life as we know it. She had crossed out the obvious answer of 2.036 because the question asked for the answer in simple numbers or some other impossible to understand wording.

Formulae were embedded in triangles with letters in each angle. I thought the original way was best like P=RT etc.

I cannot even find GCSE sylabuses on the net as it seems this business profit motive invades education as well and you have to pay to download.

One of the teachers was telling us about a new revision web site the school have subscribed to and that the kids have five logins and passwords for the paid for sites. Made me think of the Manuals Library.

Tony

 

[dextrous]

I cannot even find GCSE sylabuses on the net as it seems this business profit motive invades education as well and you have to pay to download.

These are freely available (called specifications nowadays).
Try www.aqa.org.uk or www.edexcel.co.uk as starting points

One of the teachers was telling us about a new revision web site the school have subscribed to and that the kids have five logins and passwords for the paid for sites. Tony

These are becoming increasingly popular. One which school uses a lot is www.mymaths.co.uk as it covers (teaches and assesses) all maths skills from primary up to a-level

But, enough of this hijack

 

[tamz]

the plumber/DIY man

This is where it all started to go wrong. DIY man

I could not see the relevance of big fractions when they have no relevance to life as we know it.

I had a mate who left school and couldn't do the 3 x table.
But tell him you put a yankee on at the bookies and he would tell you to the penny what you would get back. All done in his head within about 5 seconds and hadn't a clue how he did it. But that was his life. Still is