Trickling hot water bath tap.

[Jamie Tennant]

hi,
I bought a new build a couple of years ago and the hot water tap on the bath has always being a bit slow but about 2 days ago it has turned to a trickle which then starts to stop and starts trickling again at a very very slow rate.
All the hot water taps in the house work fine apart from this one the shower even works fine but this one hot tap does not,the boiler pressure is at a good level just under half way I think but Iam not sure if the hot water valve on underneath has being shut a bit I don’t know which one it is?
It’s a logic Combi ES30 I think and it’s just one bath hot water tap that is not working very well.
Thank you

 

[ShaunCorbs]

Most new build have tmv3 under the bath (blending valve to prevent the hot water hurting someone)

Can you get the bath panel off easy enough?

 

[Jamie Tennant]

Most new build have tmv3 under the bath (blending valve to prevent the hot water hurting someone)

Can you get the bath panel off easy enough?

When we first moved in my father told me about that valve and I turned it up to make the water hotter as it was lukewarm at best.

Yes I can get the panel of quite easy i recently replaced it but would that help the issue with slow water?

 

[Ric2013]

I think we need to hear the full story here. The OP has stated that the bath has always been a bit slow but now it's a trickle as if nothing has been altered, then he tells us he recently replaced the TMV. I'm confused.

 

[Jamie Tennant]

I think we need to hear the full story here. The OP has stated that the bath has always been a bit slow but now it's a trickle as if nothing has been altered, then he tells us he recently replaced the TMV. I'm confused.

The hot water has always being slow(not heating slow but a slow flow)on the bath tap nothing has changed and the past couple of days it’s gone from slow to a trickle to a stop then starts trickling again.
I’ve never replaced the TMV I replaced the bath panel

 

[Ric2013]

The hot water has always being slow(not heating slow but a slow flow)on the bath tap nothing has changed and the past couple of days it’s gone from slow to a trickle to a stop then starts trickling again.
I’ve never replaced the TMV I replaced the bath panel

Ah, that makes more sense, thank you. I think the point about removing the bath panel was not that it would help, but that someone is about to suggest something to do with the TMV.

 

[New Gas Engineer]

Maybe an airlock

 

[ShaunCorbs]

Maybe an airlock

Unlikely as it's a combi boiler

But good thinking

 

[Jamie Tennant]

Maybe an airlock

I have looked at this but was told a because it’s a Combi Boiler it’s unlikely to be a air lock.

 

[Ben-gee]

Is the hot tap stiff to turn? I'm thinking it could be hydraulically locked?

 

[Ric2013]

Is the hot tap stiff to turn? I'm thinking it could be hydraulically locked?

OP: does the cold tap turn approximately as many turns (or fractions of a turn) from shut to open as the hot one? My bet is that the taps are BOTH a quarter turn from shut to open, but, if not, Ben-gee may be on to something.

 

[Jamie Tennant]

Is the hot tap stiff to turn? I'm thinking it could be hydraulically locked?

Nope the hot tap is not stiff

 

[Jamie Tennant]

OP: does the cold tap turn approximately as many turns (or fractions of a turn) from shut to open as the hot one? My bet is that the taps are BOTH a quarter turn from shut to open, but, if not, Ben-gee may be on to something.

Both taps don’t turn a all the way before they stop maybe about a quarter is the turn on both taps.

 

[Welder]

Are there filters on TMVs?

 

[Ben-gee]

Temporarily remove the tmv; hook up the hot feed for the tmv directly to the hot tap (compression flexi should do it with no pipe work alterations), then if the tap behaves normally - replace the tmv ( although personally I’d just remove it)

 

[Jamie Tennant]

I

Are there filters on TMVs?

honestly wouldn’t know if they had filters on

 

[Jamie Tennant]

Temporarily remove the tmv; hook up the hot feed for the tmv directly to the hot tap (compression flexi should do it with no pipe work alterations), then if the tap behaves normally - replace the tmv ( although personally I’d just remove it)

Ok I’ll give this a try will I have to buy a flexi or will there be enough on it to connect?

 

[Ben-gee]

You’ll see when you get the bath panel off, I have a 900 long flexi for this type of testing - I’m sure you can easily get something to do it.

 

[Jamie Tennant]

Ok thanks I’ll have a look after work and I can leave the TMV off after wards if that’s the problem?

 

[Jamie Tennant]

Ok thanks I’ll have a look after work and I can leave the TMV off after wards if that’s the problem?

 

[Jamie Tennant]

This is what the underneath of the bath looks like

 

[Ben-gee]

Pushfit everything - what is wrong with these people, call themselves tradesmen....
Isolate both the hot and the cold valves.
The pipe entering the bottom of the tmv is the hot, connect this to the copper pipe going to the hot tap.
Disconnect one of the two elbows on the cold and cap off the pipe (I expect that tap mixes in the body and has no non-return valves).
Turn on the hot isolating valve BUT LEAVE the COLD OFF.
Test the hot tap.
If better flow, replace the TMV , whilst you are about it I would replace the two isolating valves with full bore valves.

 

[Harvest Fields]

Pushfit everything - what is wrong with these people, call themselves tradesmen..
Isolate both the hot and the cold valves.
The pipe entering the bottom of the tmv is the hot, connect this to the copper pipe going to the hot tap.
Disconnect one of the two elbows on the cold and cap off the pipe (I expect that tap mixes in the body and has no non-return valves).
Turn on the hot isolating valve BUT LEAVE the COLD OFF.
Test the hot tap.
If better flow, replace the TMV , whilst you are about it I would replace the two isolating valves with full bore valves.

New builds are covered in the stuff nowadays mate

 

[Ben-gee]

I hate it when you turn up to a job and there’s some pushfit you’re not familiar with and it needs a “special tool” to undo. But I suppose it can be quicker and that’s probably what they’re after.

 

[ShaunCorbs]

I hate it when you turn up to a job and there’s some pushfit you’re not familiar with and it needs a “special tool” to undo. But I suppose it can be quicker and that’s probably what they’re after.

its called a hammer and grips