Flow restriction in Hansgrohe rough valve?

[Andy Smith]

Hi all. New member here (English expat living in Canada) - thanks for having me!

We had our bathroom renovated which included new plumbing for the tub and shower. This consists of:
Hansgrohe Axor Citterio E valve/mixer: 36708181
Hansgrohe Raindance E360 shower head: 27381001
Hansgrohe Shower control trim: 36704001
Aquabrass LoveMe tub filler spout: 32032
Hansgrohe Starck Hand shower and cradle.

The tub now takes far longer to fill than it used to with the old mixer/taps. I can do some tests tomorrow but it’s around 30 minutes to fill the 5’ long soaker tub - which is around the same size as a typical UK bath tub. It used to take around 7 minutes.

I was not involved with the installation so didn’t get to see any testing/flushing of the valve at full-bore without the tub filler or shower head in the way. But are no leaks anywhere.

The shower head is not noticeably low flowing but I imagine you need a lot less water through a shower head to get a decent cascade than you do from a tub filler to run a bath. I understand the need to restrict flow from a shower head to conserve water but with a bath, you’re going to fill it as deep as you want to, so making it take longer is pointless - it just allows the water in the tub to cool more while you continue to run the tap so probably encourages you to run it hotter to compensate.

The Aquabrass tub filler claims to only be limited in flow based on the valve used so I don’t think the problem lies there.

Can anyone who is familiar with Hansgrohe products or this valve in particular let me know if there’s some kind of removable restrictor that might be clogged or needs replacing or removing?

Here is a link to the PDF with diagrams of the 36708181 valve - I cannot see any removable filters/restrictors but would appreciate someone more experienced confirming.
http://assets.hansgrohe.com/mam/cel...477.676872904.1537935685-849021428.1517034401

Thanks!

 

[Chalked]

Think they do 18 litres a min flow @ 2.5 bar.
Wh

 

[Andy Smith]

Thanks! I’ll test it tomorrow. (It’s almost midnight here now). Do you know how that restriction happens? Is there a removable restrictor I could take out?

Like I said, I’m all-for a restricted shower flow, as long as it’s fast enough to give you a good shower, but making us wait 30 minutes to run a bath isn’t helping the environment one bit.

From memory, I think it’s taking around 2 minutes to put out 23L so that would be 11.5L/min which is around half the rate you mentioned.

 

[Andy Smith]

Ok. I’ve done some tests. I’m actually only getting 6.75L/min from the tub filler.

6.75L/min is about one third of the 18L/min mentioned above but the Hansgrohe PDF above says that the valve is rated at 10.3 Gal/min. If I assume this is US Gallons rather than the larger UK gallons, that’s 39L/min. The tub filler claims to be only limited by what the valve can supply. So I’m getting around 17% of the flow rate the hardware should be able to supply.

Is there likely to be a removable restrictor in the valve (calling any plumbers who are familiar with Hansgrohe or similar valves!) or is this likely to be a flow limit for my hot water heater?

I should add that the flow rate doesn’t appear to change whether the mixer is set to full hot, full cold or a 100F/38c mixture.

The kitchen tap seems to run at the same maximum rate so I suspected a supply issue but I’d have expected some variation between the fixtures and hot/cold if that was the case.

 

[Chalked]

What’s your incoming mains pressure and flow.
Without seeing how it’s piped up, it’s diffic to diagnose the flow issues

 

[Andy Smith]

Totally appreciate that, Chalked. I’m just a homeowner so I have no idea what the pressure is or how to test it.

At this stage I can only think about the fact that the tub used to fill much faster than it does with the new valve. The incoming mains pressure hasn’t changed, nor has the hot water heater (we’re in the dark ages here where it comes to boilers and combi’s, etc!)

I was just hoping someone might have used these valves before and would be able to say either “nope - there’s no restriction in those valves and nothing that could go badly wrong enough with a brand new valve that would cause it to work perfectly other than providing low flow” OR “There’s a restrictor valve inside the unit that is needed to conform to some kind of California water-conservation standard. You can remove it by removing the trim plate, unscrewing the thing, and etc, etc...”

The plumber chosen by the contractor who did the bathroom reno didn’t do the best job, sadly so I don’t fancy giving him $200 (£120) to come out, fiddle with it for a while before giving up. I wish I could have brought my plumber over from England when I moved here - he was ace.

 

[ShaunCorbs]

sounds like its a mains tap on a gravity eg bigger water ways

 

[Andy Smith]

Thanks ShaunCorbs. Can you describe what that means for me - sorry - I’m a novice! Thanks!

 

[ShaunCorbs]

Guess the new set of taps have smaller water ways but designed for higher pressure e.g. They can take more pressure but loose the flow

Where as the old taps were probably designed for low pressures eg they have bigger water ways due to the low pressure