Hot water not reaching temp...?

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Any kind souls fancy helping my troubleshoot why my hot water is not hitting the correct temp? Over the last few days I've noticed that my hot water is not correct I've turned the thermostat on the side of the tank up to 70 but the water temp has not increased.

I'm pretty handy and can provide images etc to try and get to the bottom of this..

Any help would be greatly appreciated.

Many thanks :)
 
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Maximum temperature is limited by by both the stat on the side of the tank, and boiler output temperature - what is your boiler output temperature set to? Might is be set too low to achieve 70 in the tank?
 
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Thanks for the input Harry, I’ve just checked the control on the boiler and it’s set as follows.. I’ve also taken a few shots of the tank..

Thanks Steve.
 
The last three are of the boiler.
 
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If that gauge is correct, it is not far from the 70C set on the stat. Stats are not that accurate and they have a wide hysteresis (difference between the on/off set points). The grey box, splattered with white paint would seem to be the boiler stat, try nudging that up a touch and see if it helps. Mark the present set point, before you move it.

The 3rd photo, with the red adjustment knob, is a thermostatic mixer. It mixes hot and cold water going to your hot taps, to limit how hot the hot supply is. It might be worth checking (with hot tap running) the hot going in at the top and comparing it to the mixed output pipe coming out on the right. If set at max. (as it appears to be) hot going out should be the same as hot going in. If there is a difference, then that mixer is faulty and allowing cold in.
 
Many thanks Harry, I’ll have a try in the morning and report back. As always, appreciated
 
Good morning Harry, the issue seems to be with the red adjustment mixer, as there is a difference between the hot going out.

What I did notice is that I am unable to adjust the red adjustment knob, trust this should move? Many thanks Harry.

Steve.
 
Good morning Harry, the issue seems to be with the red adjustment mixer, as there is a difference between the hot going out.

What I did notice is that I am unable to adjust the red adjustment knob, trust this should move? Many thanks Harry.

Steve.

I don't know about the one you have, but the one I have has a large headed screw in the top of the adjuster, which locks it from being adjusted. If yours is similar, undo the screw a few turns, to allow it too be turned.
 
Thanks Harry I did think of adjusting that however I can get a driver onto it due to the black thing in the photo being in the way
 
Many thanks Harry, I’ll have a try in the morning and report back. As always, appreciated

Oh dear, yes - I see what you mean, that is really bad layout, somebody didn't think it though. Is it a Philips screw or does it need a flat bladed driver? If the later, you should be able to turn it with the edge of a knife blade. You can also buy right angled screw divers, where the blade is bent at right angles. If you have a vice and an old cheap screw driver which is soft, you might be able to bend it.

Another way is to cut a short section from the end of a suitable screw driver off, then grip it tight with a self grip wrench to turn it. I doubt the screw is very tight - its only intended to prevent people playing the the setting of the mixer.
 
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Great shout Harry and we’ll done. I’ve managed to get it off and now have the attached. Can I just check with you what’s next before I proceed?

Also is there likely to be an underlying problem that I should be looking to address?

Cheers mate, Steve.
 
You were not supposed to remove it completely, undo the screw enough to be able to turn the red handle.

Can you refit the handle back in exactly the same place, with the screw, but leave the screw undone just enough to be able to turn the hanle?

When you have done that, looking head on at the screw, it needs to be turned clock wise to increase the temperature.

Idea of the mixer, is that you can store in the cylinder much hotter water and the mixer will restrict the temperature at the hot taps, to what ever you set the mixer to. Good where elderly people and youngsters might turn hot taps on.
 
Oooops. Yep I've got it back on and adjusted and the water appears to be back up to temp! Great work!! :)

Do you happen to have any thoughts as to why this may have happened? I'm just trying to understand the system and be able to trouble shoot better in future.

Something that I didn't mention and unsure if there is likely any knock on effects is that I believe that this tank is duel purpose and also serves hot water for the underfloor heating around the house.

Can I also ask another related Q.. When I purchased the house there was a wood burning stove 'yet' to be fitted that is piped back to the water tank. (I had this fitted a couple of years ago now) I've just noticed to the side of the tank that there is a small boxed unfitted thermostat (same as in picture one). I trust that this should have been fitted at the time the stove was!?

I've had no issues with the setup and have run the fire over winter for the last couple of years. My only observation is with the flow and return that exit the rear of the stove the cold water being fed in reaches temp very quickly. I expected this to take much longer if it was truly heating the underfloor heating throughout the house?

Thanks again Harry, you have been a great help! :)
 
Oooops. Yep I've got it back on and adjusted and the water appears to be back up to temp! Great work!! :)

Do you happen to have any thoughts as to why this may have happened? I'm just trying to understand the system and be able to trouble shoot better in future.

If it used to be hot, then became cooler - someone must have adjusted that mixer temperature setting. If you moved in and found the hot water too cool, perhaps the previous owner altered it...
 
Hi Harry, I'm 100% sure that the mixer hasn't been adjusted. The water temp has always been hot and consistent in the house. Before posting I did notice that the water temp on the tanks thermostat was set to 50 and assumed that this could have been knocked by the kids trowing stuff in the room. I adjusted this first to 60 and noticed no difference in the water temp over a couple of days then knocked it up to full at 70 with no diff before posting here..
 

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