New mixer tap not activating pump.

[Pandapaws]

Hi, complete newbie so hope you don't mind me asking for help...
I've just had my dripping thermostatic bath/shower mixer tap replaced, which was fab for the first few days. However, it is now taking ages for the hot water pump to kick in when using the bath or shower for the first time. This morning it took nearly four minutes! I'm wondering if the thermostatic valve could be faulty? The pump was working perfectly well with the old tap, and once it kicks in it's fine, it's just getting it to kick in that's the problem!
The tap is ten days old so I'm wondering if I should just return it and try a new one.
Thanks so much for reading this!

 

[steadyon]

The taps may have a filter, usually one on each of hot and cold. If they are easily accessible I'd suggest checking / cleaning them, particularly. If they are clogged they may not allow enough flow to start the pump.
Make, model and photograph of shower might be helpful.

 

[ShaunCorbs]

Is it suitable for low pressure eg gravity flow ?

 

[Pandapaws]

Is it suitable for low pressure eg gravity flow ?

Hi, yes it is - from 0.5 bar according to the blurb. When the pump kicks in it's fine.

 

[Pandapaws]

The taps may have a filter, usually one on each of hot and cold. If they are easily accessible I'd suggest checking / cleaning them, particularly. If they are clogged they may not allow enough flow to start the pump.
Make, model and photograph of shower might be helpful.

The taps are new, only fitted a week ago. Would the filters still need cleaning?

 

[ShaunCorbs]

Hi, yes it is - from 0.5 bar according to the blurb. When the pump kicks in it's fine.

There’s your problem wrong spec for your pump two options change the pump to a negative head / universal or change the taps

 

[Pandapaws]

There’s your problem wrong spec for your pump two options change the pump to a negative head / universal or change the taps

I think changing the taps is the easiest option! What would I need to look for though? They all look the same...

 

[ShaunCorbs]

Normal rubber washers and not 1/4 turn cartridges

 

[Pandapaws]

Normal rubber washers and not 1/4 turn cartridges

I'm so sorry to be a pain but that doesn't mean anything to me I'm buying them online and none of the taps I've seen have this sort of information. Can you recommend a particular mixer tap please? Thanks so much!

 

[Bribodog]

your new taps will have non return valves fitted and the head of water you probably have is struggling to open them

 

[Pandapaws]

There’s your problem wrong spec for your pump two options change the pump to a negative head / universal or change the taps

your new taps will have non return valves fitted and the head of water you probably have is struggling to open them

Hi, thank you! So I'm guessing the delay is waiting for the pressure to build up to open the valves....
Is it possible to get mixers without non return valves?

 

[Bribodog]

That’s exactly it - and once opened it is fine. I had exactly the same problem and I “disabled “ the non return valve (don’t tell anyone!) I no longer have an issue

 

[Pandapaws]

Thank you

That’s exactly it - and once opened it is fine. I had exactly the same problem and I “disabled “ the non return valve (don’t tell anyone!) I no longer have an issue

So much

That’s exactly it - and once opened it is fine. I had exactly the same problem and I “disabled “ the non return valve (don’t tell anyone!) I no longer have an issue

That's fab! Thank you so much for your help.... and for making it so understandable!