New Shower Install Causing Issues - Please Help/Advise!

[Bazzy]

That means it's not a boiler problem

Is there an ISO valve on the new tap cold ?

Hi,

Thanks kindly - Great to know its not a Boiler problem - very reassuring!

Strange that the Kitchen tap went Hot/Cold but the new Bathroom one did not since you say it's not a boiler problem?

I have no idea what an ISO valve is & if the tap has one - I will do some googling and may get in touch with Hans Grohe to ask them & get back to you.

May I ask, what does this ISO valve on the new tap do & will if affect water temps to other taps/showers? Please bear in mind, this new tap delivered uninterrupted hot water.

Many Kind Thanks,
Bazzy!

 

[Welder]

Part of learning is asking questions - even if they might be as infuriating/asinine as mine but I hope you can see the intention is sincere & to solve issues - not to waste anyone's time here.

You gave it some thought. A great start.

Think of your tap like the end of a pipe connected to your boiler.

When you stop the hot water running all the water in the pipe to the taps cools down. Pretty quickly. Let's say the pipe contains 10 litres of water.

So, your old tap allowed water to flow out fast. Once it cools it has to flow out so its place can be taken by hot when you open the tap. That means 10 litres has to flow out before the warm stuff can reach you.

If opeing the old tap takes 1 minute before the hot water reaches you, then the flow rate from that old tap is 10 litres per minute - geddit?

New taps have a reduced flow rate. Say your new one has a flow rate of 5 litres per minute (to comply with legislation). You still have to get rid of the 10L of cold water sitting in the pipe before teh hot gets to you so at 5 litres a minutes it will take two minutes to do so. That is, it will take TWICE as long for the hot to reach you.

This is why your water takes longer to 'get hot'.

HTH

TO FORUM MEMBERS
I swear, if ANY of you lot even mention pressure I'll hunt you down, cut your balls off and feed 'em to the I'm a Celeb Crocs...

 

[king of pipes]

Better not go there then . Kop

 

[Ben-gee]

Baz, to use your numbers - fully open the tap that allows 10 lpm and 10 litres will come out in one minute. That means from boiler to tap 10 litres have moved, that part of your system is ALL 10 lpm now. Your statement that it is 17 lpm up to the tap is wrong, think, if it was 17 litres arriving at the tap and 10 coming out of the tap what happens to the other 7 litres?
Each “leg” of your plumbing has a different flow rate, which is determined by the item with lowest flow rate in that “leg”. HTH

 

[Bazzy]

Hi All,

Now that the tap issue has been addressed & from the information both provided & requested as to the issues with the hot & cold alternating water from both the showers, can anyone please offer any insights as to what is causing these issues & possible options to solve them?

Many Kind Thanks,
Bazzy!

 

[Ben-gee]

The first thing I would do is check the functioning of the non-return valves in each shower and then move on to any mixer taps.
Stop saying everything was alright before, by this logic nothing would ever break or become faulty, if only. You need to maintain a good relationship with our plumber, we are sensitive artistic types, you’ll be surprised how we respond to respectful treatment rather than blame/confrontation.
Don’t forget a brand new item can be faulty.