Grohe thermostatic bath/shower mixer

[steve124]

Hi,

I have purchased a Grohe thermostatic bath/shower mixer off Ebay a few months ago and am experiencing problems getting enough hot water into the bath.Estimated age approx 3 years old.

I do not know the exact model number but is similar but not identical to the new Grohtherm 3000.The difference being that when you sit in the bath the temp selector is on the RHS and the bath/shower selector is on the LHS.
On the Grohe website the new one is shown reversed.

Both entry points are 1/2 bsp.

Which side should the hot water be connected.....the left or right as you are sat in the bath??

I was given no instruction manual so its a 50/50 bet I've done it wrong.

Also is it possible the built-in water strainers could be blocked with limescale as hot water pressure is very low but high on the "normal" tap in the nearby sink.

Thanks for any help.

 

[John506]

Are they quarter turn?

Hot always goes on the left, cold on the right, the tap should indicate with red and blue.

I would also fit check valves on both the hot and cold to prevent the risk of backflow if the water is mixed inside the spout.

 

[jammmy]

On the grotherm I fitted there was a cap that could be removed on the hot/cold adjuster to reveal a screw that could be turned to fine tune the factory set 38 degrees. Maybe worth getting a thermometer and making sure it's set right, though mine didn't need any.

 

[steve124]

Hi,

The LHS bath/shower selector is quarter turn but the RHS temp adjuster turns about 180 degrees.

I didn't notice any red or blue markings on assembly although i have connected hot to the left hand side.(As sat in bath).The LHS pillar mount is too hot to touch but the water coming out regardless of temp setting is no more than lukewarm.

There is a noise like trapped air in the hot water pipe so maybe your idea of the check valves is a good one.

Thanks for your reply.