A new Megaflow and water pressure

[Tazer]

Hi All,

I recently had a new Megaflow 300L installed with the Vaillant 637 System Boiler.

The main water pipe is a 32mm blue pipe which comes to the side of the house, then for a few meters drops to 25mm then drops to 22mm before it goes into the water softner


The pressure gauge before the water softner shows me 3bar.

The problem I have is the loft and 1st floor bathrooms which we just finished plumbing the water pressure isnt great. On the ground floor the water pressure is suberp.

Any ideas on what else I can do to increase the water pressure for the loft and 1st floor. Is it worth upgrading the few meters of 25mm pipe to 32 and then reducing it to 22.

Its been baffling me for quite some time and not sure what I can do.

Any help/ suggestions would be great

 

[Agile]

Its not possible to give any useful advice without knowing what the dynamic flow rate is at your property.

As you should know installing an unvented cylinder must be done by a qualified person. The obvious question is what does the installer say about it?

Most water softeners have a considerable flow resistance and many are unsuitable for use with an unvented cylinder. Whats the make and model of yours and how was it chosen? What is the size of the inlet and outlet connections?

Do you think that you understand the relationship between pressure and flow?

The FAQ section on this site may give you some help.

Tony

 

[Tazer]

Hi,

Im not to sure what the dynamic flow rate is. The inital plumber who installed it screwed me over when it came to the bathrooms. Literally said he couldnt do the job so had to get some new plumbers to finish of the job.

But he did finish the new installation off.

The water softnew I have is the Monarch MAXI with the 22mm inlet and out let connections. To be honest the water softner hasnt been plugged in as of yet so the water is direct into the boiler/ megaflow

All isolation valves are 22mm with the bigger ball bearings and stop cocks used for the loft and 1st floor to switch on/ off the water.

Yes I understand the pressure and flow aspect. But puzzled why the donwstairs has excellent pressure and not on the first/ loft.

Ive used 22m in all 3 bathrooms in each floor so the flow rate would be good, but surely having just under 3bar pressure comining into the house and going into the megaflow will not be reduced significantly for the first/loft bathrooms

 

[Agile]

As I said, its not possible to come to any conclusion what the problem is without know in the dynamic flow rate is.

Many parts of London have a relatively low dynamic pressure even though you seem to have a high ( standing? ) pressure but there does seem to be something wrong but as stated without measurements its difficult to know whats wrong and I dont guess without technical information.

A large difference in flow rates on higher floors would indicate a low dynamic pressure. Each floor has about 0.3 Bar lower pressure on account of the height increase.

I cannot find a Monarch Maxi listed on their web site.

Tony

 

[simond]

The problem I have is the loft and 1st floor bathrooms which we just finished plumbing the water pressure isnt great. On the ground floor the water pressure is suberp.

7 litres a minute looks suberp (sic) out of a small bore kitchen tap, or a basin, which I expect you are using as your benchmark.

7 litres a min out of a bath tap doesn't look very good at all.

I suggest you measure your flowrate where 'it is good' using a bucket or a litre bottle and get a litres/min reading.

If it is less than 20l/m you have made the mistake of thinking a blue pipe is the answer to getting an unvented to work.

There are plenty of heating technicians and plumbers out there who will agree with you. Expensive mistake.

 

[Tazer]

Hi Guys

Thanks for the update.

The water softner is the Monarch Master not maxi

http://www.monarchwater.co.uk/htm/home/ultimate/choosing_ultimate.htm

By checking the water in the bucket, should I check it e.g. outside front garden where I have an outside tap coming off the mains.

Or is it worth while checking it i.e. Kitchen sink. This will be going through the megaflow.

ive just checked the main gauge again where I have the blue mains coming going to the 22mm copper, there is a reducer with a guage and this is reading 2.9 Bar pressure.

Ive read a few sites and alot of people have suggested, draining the system and regenerating the bubbles.....

I have a bathroom on the ground floor, the pipe is 15mm at the moment and will be upgraded to 22mm but the pressure here is excellent.

Also correctly said, its been very expensive in terms of getting new kit in and making sure good pressure was delivered.

 

[holty]

have to say i agree with agile.its something having static pressure.but when its being used, then thats were working pressure comes in.and as simond has mentioned bath taps show poor rates compared to a sink taps etc.how many floors do you have etc were is the softner/gauge,in the basement?i ask is becasue you can lose pressure due to height. 10m=1BAR. so that will have an effect.to many possibilities to suggest without looking at the job.

 

[simond]

If you have 2.9bar static there is not that much effect the 1st floor will make on performance.

You have a poor flow rate and that is either due to a major pipe restriction in your new pipework - unlikely - or you have a below par flowrate coming into the property.

The air bubble is just there for expansion and even if your Megaflo is dumping out of the PRV, the effects would be seen everywhere not just the ground floor.

Outside tap would be as good a place as any to measure.

 

[holty]

If you have 2.9bar static there is not that much effect the 1st floor will make on performance.

ahh missed the bit on the OP first post. of first floor bathrooms.so ignore my post.totally missed that point.

 

[Tazer]

Its just heart breaking when you spend so much money in trying to achieve what you have been told.

Guess I wont be using the body jets in the loft..........

From the main blue pipe I have a stop cock then the gauge which is fitted onto a pressure reducing valve for the water softner. At that point it shows me 2.9

From there it will go into the water softer and then the megaflow which are all close suited next to one another at the side of the house. The water softner is not connected, well till the weekend.

So is 2.9bar my static pressure?

I will check out the main tap over the weekend or better still, I can open the valve on the water softner (before I connect the water softner) and check out the dynamic flow rate there as this will give be a better reading.

 

[simond]

2.9 bar is the reading of static pressure, assuming there are no water drawoffs running downstream when you take the reading.

You could take the reading at the softener, but I still think you are unduly preoccupied with pipe sizing being the cause. A reading at the outside tap will tell you what you need to know.

If there is a PRV on the water inlet to the softener, it might be worthwhile taking it off and checking the gauze , just in case it is blocked with crud from Thames Water.

 

[Tazer]

Good point Simond - in regards to the PRV and checking that. The good thing is the main pipe comes straight in to the side of the house so can check the dynamic flow rate there.

Is it simply getting a litre bottle or bucket and timing the flow........so special equipment required.

Also one point to note is I do have alot of cock stops i.e for the first floor bathroom, loft bathroom, ground floor bathroom all in this area.
Is a cock stop a full bore? or is it better to have an isolating valve with a full bore

Thanks

 

[simond]

We use full bore lever arm valves where necessary on pressurized water systems. Stopcock is a little more restrictive but this won't be your problem.

Just use a receptacle with a known capacity eg: 10 litre bucket, and time how long it takes to fill, eg: if it fills in 20 secs, you have 30 litres per min. That would be exceptional, by the way!

 

[Tazer]

Hi Simond

I carried out the test 3 times and the average was 3.3 seconds to fill a 3 litre bottle.

First time I got 3.2, second, 3.5 and 3rd 3.2.

I filled it from the water softner inlet 22mm pipe. This is placed just after the main stop cock and pressure guage. Re checked the pressure guage and was reading 2.8 Bar pressure.

Now that we have the results, does this mean anything in terms of why my pressure is pretty sucks on the 1st and Loft.

Also all my pipe work is 22m esp for the bathrooms and main runs of the central heating.

 

[simond]

A 3 litre bottle in a little over 3 seconds?

I'm sorry Tazer to doubt you, but that is a little under 60 litres per minute. That is fire hydrant territory...... are you sure?????