New Shower Install Causing Issues - Please Help/Advise!

[Bazzy]

Hi All,

We are experiencing some problems with both our Showers in our home. We have two Showers - in the upstairs bathroom & in a wet room downstairs. They are both connected to a Worcester Bosch 35Cdi Combi Boiler (older version) which gets regularly serviced every year.

In our upstairs bathroom, for over 15 years of so, we had a recessed Aqualisa 609 with the expensive Aqualisa Varispray Hand Shower Head (without any flow restrictor). About 3 times during this long period, the water would alternate between hot & cold & after consulting with Aqualisa, a new cartridge always solved this problem.

In our downstairs wet-room, we have a Bristan Prism Shower with two way diverter & the Hand Shower Head was a Mira Eco (again, without any Flow restrictor). This unit was installed in 2012 & we have not had any problems with it till now.

The Aqualisa 609 developed a fault & caused a leak which damaged the kitchen ceiling below. The Plumber found that there was a crack in the recessed shower body & we had to get a new Shower valve fitted. Aqualisa supplied us with their new Recessed model: Dream DRM001CA - it uses the same cartridge types as the 609 series it replaced.

Please keep in mind, that at NO point either before or after the leaks, was there any water temperature issues with any of the two shower systems - they were both able to maintain the temperature set - even if one took very long showers & that too if both showers were running at the same time. This to me, implies there is nothing wrong with the boiler in any way.

After the plumber fitted the New Shower unit (with the brand new cartridge), BOTH showers are now experiencing problems in that we are getting alternating hot & cold water - this issue simply did NOT exist before the new shower was fitted.

The Plumber kind of fobbed me off said that either the boiler is faulty or that it cannot keep up with the demand each of the showers is making upon it which to me sounds like absolute nonsense because:

1) The new Shower seems to be less powerful & delivers not a strong flow as the 609 it replaced
2) Both Showers were working just fine (either on their own or in tandem use) before the new one was fitted upstairs
3) The Boiler is regularly serviced
4) It handled the 609 Shower for over 15 years just fine
5) It has handled both Showers just fine since 2012
6) It seems something about the installation of the new Dream Shower upstairs has affected the water temperature to both of them.

The only changes I made was to change all the Hand Shower Heads to another brand (like the other handsets, these too do not have any flow restrictors). I did change the small overhead drencher to a much larger one but was told by the good folks here that it was simply way too big for our system so I went ahead & replaced it with a smaller one which is inline with our boilers capability. It makes no difference - I have swapped them all round a number of times but still get this alternating hot & cold water on each Shower unit - Hot for about a 1.5 mins & then cold for anything between 45 secs to 1 min it seems.

We also had a new vanity unit with a sink installed along with the Shower in the upstairs bathroom. The old mixer tap (a very cheap, generic model that was installed over 15 years ago) could not be used as it was too small so I went & bought an expensive, high quality Hans Grohe one - model: Logis Mixer 100. The old & very cheap mixer tap delivered a generally strong water flow & it would deliver hot water quite quickly but this new high end Hans Grohe one has quite weak water flow in comparison & it takes ages for the water to get hot - around 2 minutes - surely this cannot be right?

Can anyone please kindly advise as to what might be causing these issues (considering they only surfaced when a new Shower & Basin Tap was installed upstairs) & with possible solutions so I can then go back to the Plumber armed with information from experts so he cannot fob me off with excuses & can apply your solutions & not just blame the boiler & ask us to get a new one installed with all the huge costs that would involve.

Although I am just a consumer, based on the above, I am convinced that there has either been in installation issue or that he messed something up on the whole water system when installing the new Shower & Tap on the vanity unit.

Very Many Thanks To All!

Bazzy!

 

[king of pipes]

With the shower running go to the boiler and watch what happens if it shuts down and keeps firing up on off, on off and does not keep constant then it's a restriction in the system possibly caused by the alterations carried out ? It may not be the fault of the new shower or grohe tap rule this out first . Kop

 

[Welder]

Baz.

First. You have convinced yourself the plumber is at fault. Stop. The very simple fact is that many things could, and do, happen that are oft unrelated in real life. So, as KOP quite rightly intimates, the only way forward is to discard this little obsession and to look at it entirely objectively. If I had a £ for every person who called me convinced it was the moon rising that made their hot water go cold etc... 🙄

Second. Logic & objectivity when fault finding is the key. NO assumptions can be made whatsoever. Follow KOP's advice and between us you will be delivered from the frustration 😉

Lastly. Hansgrohe (German company but part of the Masco Group) taps are designed to comply with EN200 - the definitive and mandatory European standard for taps. An essential aspect of EN200 is flow limitation because it has been proven to save both energy & water for users. This is why you get less flow from the new tap than the old. See, already for one of your issues there is no conspiracy 😀

EDIT.
I've just looked at the images properly. I noticed that one of the hoses looks quite kinked. When was the last time they were changed?

 

[Riley]

Yes. Not all plumbers are out to rip you off and if you treat a contractor with respect they will you. Things do change following new installs. Also your boiler is old. It would maybe have worked for two showers perfectly out of the box but it’s older, scaled, parts are tired or partially obstructed so performance will suffer over time. I’m not saying get a new one but be realistic in the age of your product. You had to replace a shower valve after however many years, trust me your boiler has worked 100 times harder during that time.

 

[Bazzy]

Hi All,

Thanks to all for the responses so far - much appreciated! I do not wish to automatically blame the Plumber but he did say that he checked things beforehand & said the boiler was working fine (we were also discussing installation of a Water Softener & a Boiler Filter as well as anti scale devices & moving the boiler to another location) so he checked all the pipes to the boiler & its operation. After this issue, he was extremely flippant & sort of said, your boilers is at fault or not powerful enough or something like that very dismissively so it in this context that made me question things. He took over month & half to install the vanity unit/sink, new shower & tile a small area in the shower cubicle as he would always say he would turn up but rarely ever did! He made me buy a new Air Extractor & has fitted it bit not connected it - been well over 2.5 Months now!

I have done test as per Kops advice as best I could with both of the showers & a main hot water kitchen tap to see what happens - When any shower/tap is turned on the Red Flame Light on the Boiler illuminates & it fires up. When it switches itself off, the Red Flame Light goes off. The Pressure was 1.4 bar with the Downstairs Wet-Room Shower On & 1.8 Bar with the New Aqualisa Dream Shower On if that might have any bearing?

These were the results:

Upstairs New Aqualisa Dream Shower When Switched On & Hot Water Selected:

Boiler Runs For: 1m 32 Secs
Boiler Stops For: 10 -12 Secs

Boiler Runs For: 1m 20 Sces
Boiler Stops For: 15 Secs

Boiler Runs For: 1m 30 Secs
Boiler Stops For 15-20 Secs

Boiler Runs For: 1m
Boiler Stops For: 10-15 Secs

Boiler Runs For: 1m 46 Secs
Boiler Stops For: 10 -12 Secs

Boiler Runs For: 1m 28 Secs
Boiler Stops For: 15 Secs

I Stopped At This Point.

Downstairs Wetroom With Bristan Prism Shower When Switched On & Hot Water Selected:

Boiler Runs For: 2m
Boiler Stops For: 10 -12 Secs

Boiler Runs For: 1m 48 Sces
Boiler Stops For: 15 Secs

Boiler Runs For: 1m 50 Secs
Boiler Stops For 10-15 Secs

Boiler Runs For: 2m
Boiler Stops For: 10-15 Secs

Boiler Runs For: 1m 40 Secs
Boiler Stops For: 10 -12 Secs

Boiler Runs For: 1m 50 Secs
Boiler Stops For: 10-15 Secs

I Stopped At This Point.

Kitchen Hot Water Tap At Max:

Boiler Runs For: 4m 28secs
Boiler Stops For: 10 -12 Secs

Boiler Runs For: 3m
Boiler Stops For: 15 Secs

Boiler Runs For: 2m 30 Secs
Boiler Stops For 13 Secs

Boiler Runs For: 2m
Boiler Stops For: 14 Secs

It them seemed to stay a a 2m On/Off Cycle another 3 or 4 times before I switched the Kitchen Tap off.

Hopefully, this might give you experts something to gauge what might be going on & causing the issues - I really hope so!

As for the New Hans Grohe Logis 100 Basin Mixer Tap - I can now appreciate that it was designed to limit water flow (wish I had known that before buying it!) but even so should it really take so very long just to get the hot water to finally start coming out? It can take anywhere between a 1m & 40 Secs to 2mins - the previous one which really was a very cheap generic mixer tap - the type you see on Amazon/ebay for about £12-£15 used to deliver the hot water so very much quicker at full temperature?

As for the Shower Hoses, the one on the Aqualisa Dream upstairs is Brand New - it was part of the contents in the whole Shower Box & the one downstairs in the Wet-Room is probably about 2.5 to 3 years old.

Many Kind Thanks All,
Bazzy!

 

[ShaunCorbs]

Do you get constant hot water from the taps after it's come through hot ?

 

[Welder]

As for the New Hans Grohe Logis 100 Basin Mixer Tap - I can now appreciate that it was designed to limit water flow (wish I had known that before buying it!) but even so should it really take so very long just to get the hot water to finally start coming out? It can take anywhere between a 1m & 40 Secs to 2mins - the previous one which really was a very cheap generic mixer tap - the type you see on Amazon/ebay for about £12-£15 used to deliver the hot water so very much quicker at full temperature?

Right. This is the point where you have to, brace yourself lad, start thinking for yourself.
Re-read my post.
Then read yours.
Apply what each of us is taught in junior school, then come back to me and explain why what is happening is happening.

The point of you coming on here is to learn. If you do not, we are ALL wasting our time as its akin to changing your nappy instead of potty training you. 🙄🙂

I'll give you at starter for 10. F L O W.

 

[Bazzy]

Do you get constant hot water from the taps after it's come through hot ?

Hi,

I just checked with hot water taps in the kitchen & upstairs bathroom (the new Hans Grohe one.

The Kitchen Tap had alternating hot/cold water - I went through 3 cycle of about 2 mins hot & 30-45 secs cold.

The tap in the upstairs bathroom had no issues for the time I tested it - a full 5 mins & it remained hot throughout this time.

Hope this helps?!

Many Thanks,
Bazzy.

 

[ShaunCorbs]

That means it's not a boiler problem

Is there an ISO valve on the new tap cold ?

 

[Bazzy]

Right. This is the point where you have to, brace yourself lad, start thinking for yourself.
Re-read my post.
Then read yours.
Apply what each of us is taught in junior school, then come back to me and explain why what is happening is happening.

The point of you coming on here is to learn. If you do not, we are ALL wasting our time as its akin to changing your nappy instead of potty training you. 🙄🙂

I'll give you at starter for 10. F L O W.

Hi,

My apologies for my ignorance on the subject matter & for any consternation/frustration caused - it was not my intention.

I am assuming by giving me the hint: Flow, you are suggesting that as the FLOW is limited AT this Hans Grohe Tap then it is taking longer for the water to heat up & travel all the way from the boiler downstairs to the tap all the way upstairs - am I on the right track? I am sorry for being dunce - this is not my expertees which is why I came for answers but would also be delighted to learn.

Just for general info, when I did a basic timed water flow check with the Kitchen Tap sometime ago - it came to around 17 Litres per min - the good folks here confirmed that would likely be the water flow rate for the whole house.

I guess I am not understanding properly - I can appreciate that once the 17L per min FLOW rate reaches the Tap it is THEN being limited/restricted at THAT point - no problem.

However what I am failing to understand & am willing to learn about is that why does any restricted flow rate of & at any tap affect the temperature delivery of the water when that is the job of the boiler?

As soon as I turn on the tap to max hot, the boiler pretty much kicks in straight away so the water starts heating it up almost instantly & sends it to the tap at 17L/min where as you say it is being restricted - fine - but why would then this affect water temperature or rate of water temperature delivery when the tap is set to max hot just because the flow is restricted?

To the logic of a novice like me, this would imply that the boiler would send hot water as demanded at it's normal flow rate (17l/min) & max temp (say 60 degrees) but just that it will flow out at a lesser rate (say 10L/min) ONCE it PASSES THROUGH this EN200 restricted tap than on non restricted taps but still at 60 degrees - the the time to temp set & temp delivery rate should then not be affected should it?

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.

Feel free to rip into me!

Many Thanks,
Bazzy.

 

[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.