Any plumbers here? Pics included, please help me identify whats what :-(

Jez

Jez

Jez

Caporegime
Joined
18 Oct 2002
Posts
33,073
Hi,

Edit: TLDR: Tank of water is nice and hot and as such the heating sources are not firing much, but the water out of the taps is luke warm (but pressure is fine).

I appreciate these pictures look a mess, the pipework doesnt mean a lot to me, but i am hoping that it may look simple to someone on these fine forums who actually has a clue about hot water systems! :)

I am not actually sure what type of system this house has, is it unvented? When turning off the cold mains supply all water trickles to a halt including the hot taps, after a little initial surge?

The issue we currently seem to have is that water is only coming out luke warm, almost too cold to shower, this happened suddenly one day, and i have no idea why. The immersion heater works fine, has a new stat, and upon pulling the stat out it is boiling hot and therefore not firing much. The whole tank feels very nice and warm so i know this is heating. The immersion isnt kicking in much (it fizzes when it does - always has) compared with before this happened, its almost like hot water isnt being drawn off the tank and is somehow being diluted with cold. As i say the immersion has a new stat, and the tank feels just as warm as ever, but it is firing noticably less which my layman diagnosis has put down to hot water not exiting the tank?

So i know the top tank with internal float does the central (radiator) heating header, i know this as caused a leak before in our heating circuit and this emptied out :p
20131016_163518%20%28Medium%29.jpg


So this is where i dont know what the heck is going on. I figure that the electrical white & grey item above the immersion is the boilers temp sensor to call for heat (this isnt firing much since the issue, as the tank is already hot). The red pump i think is the boiler heating loop pump? (the boiler is downstairs - kerosene fired). The rest of it i have no clue about, the silver thing, the other silver thing, and what seem like piped with a million junctions.
20131016_163544%20%28Medium%29.jpg

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I basically dont know how to even start resolving this luke warm water issue. If i leave the boiler switched off and use the immersion only (what we usually do, kerosene is a pain) its hardly firing, the tank feels really warm, but we run a hot tap receiving luke warm water for over 10mins solid, and the immersion barely kicks in and its stat still feels boiling hot as it should if removed from the slot in the heater. :(
 
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So I am no expert, but that silver box with multiple connections is your flow control valve most likely, so depending on the signal sends water for heating to the rads, the taps or both. It may be this is faulty hence your problem, most of them have a manual overide so you can force the position to taps or rads. It might be worth trying that.

You are correct the red unit is the heating pump for water circulation.

The box that connects into the tank is most likely a sensor unit of some kind for temperature.

As of the other white box, no idea.
 
the the silver box that says Honeywell on it is likely controlled by a thermostat somewhere in your house that also says honeywell.

when the thermostat goes under temp the metal box allows water to flow to the radiators
 
Many Thanks for the replies so far :)

Ok, so i get the motorised valve, and it appears to be OK and oprates automatically (i can hear it turning as expected when i play with the system.

What i cannot understand is why the output from the system is only luke warm, with only occasional heating kicking in :(
 
If the tank is definitely already warm but the water being drawn off it cold it may be the mixer valve (the brass valve with the white head). This should mix the hot water from the cylinder coil with mains cold water.

Turning the white head open more may help (it might have been inadvertently turned down) but usually it will be the mixer faulty.
 
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Ok so thats what that thing is? :)

Why does it mix cold water in with the hot water at all? I just want the contents of the tank?

This is probably a stupid question, but i didnt ever claim to know anything about this :D
 
has any work been done on your boiler/heating recently ?

nothing to do with my hot water but mine recently had a thermostat fitted for the radiators including one of those honeywell metal box things and one of the valves got blocked up with crud so no hot water would get to my radiators.

the guy who fixed it said it's fairly common and fitted a valve with a larger diameter.

maybe a valve is blocked with crud so no hot water/barely any is making it to your shower and taps.

or you have a failed thermostatic valve somewhere most showers have them built in for health and safety these days they are supposed to make it so the water mix can only reach some lame temperature and stop people getting burnt
 
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I think the issue has to be the tank end, as all taps and outlets around the whole house are the same luke warm temperature. (3 bathrooms + kitchen taps)

What i dont get about the blockage idea, is the pressure being fine even with a normal tap set to full hot :(

No work has been done on this since we bought this house, or for many years before that looking at the state of it all :D
 
Jez said:
Ok so thats what that thing is? :)

Why does it mix cold water in with the hot water at all? I just want the contents of the tank?

This is probably a stupid question, but i didnt ever claim to know anything about this :D
Click to expand...

Yep, top pipe into it is the hot out of the cylinder, right hand one is cold and the bottom one marked MIX is the outlet to the taps. When the cylinder is warm and you turn the tap on the hot should flow through that valve, mix with cold and go to your taps. The temperature out of these thermal store cylinders is usually very hot and the valve gives you a bit better control of it.

If this is fully open anti clockwise towards the + marked on top and the pipe into the mixer is hot then you should have hot water. If not there could be a problem with the mixer. Though if the pipe into the mixer isn't warm it could be an issue with the hot water coil in the cylinder scaled preventing it picking up heat as cold water flows though. Or there isn't enough heat in the cylinder.
 
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This is just what i needed, thankyou very much for explaining what some of the pipework is doing and the function of it :) I now at least can see where the hot and cold are coming and going.

That tap was stuck HARD, but i just got it with a large pair of grips. If i turn it right down i get freezing water out of the taps, and if i turn it right up i am getting boiling (steam coming off) hot water, the heating elements also kick in as i would expect when i run it boiling hot like this - HURRAH! :)

This unfortunately leads me to the next question (even though i am very glad to have some hot water now!), the flow from having it full hot is very low.

This leads me to wonder: Is there perhaps a new partial blockage out of the tank before that tap? This combined with the low flow from full hot on that tap, and the sudden dip in tap temperature?
 
im not sure why you would have a thermostatic mixer on a cylinder? do you have underfloor heating or anything?
the white box clipped round the pipe looks like some kind of scale inhibitor it uses an electronic or magnetic field to reverse the polarity of the particles so the scale wont stick, the silver vessel could be for expansion or some kind of shock arrestor(anti water hammer) but a strange setup for a fortic cylinder.
 
No (wet) underfloor heating no, the cylinder just does the radiator central heating, and the hot water.

That tap definitely adjust the water temp, if i feel the pipes going in and out of it it matches exactly as per the_dead_parrot's advice and reflects in the water coming out of the taps.

Why it is there....i am not quite sure, you guys tell me :D I realise it does give an element of control (i can choose my water temp from it), but i can also do that from the immersion stat, and on the boiler control unit itself (the tank temperature).
 
Jez said:
Why it is there....i am not quite sure, you guys tell me :D I realise it does give an element of control (i can choose my water temp from it), but i can also do that from the immersion stat, and on the boiler control unit itself (the tank temperature).
Click to expand...

Would this help you have hot water for longer? If you set it fully open and set your desired temp on the thermostat you will have the capacity of the tanks worth of hot water.

If you have the tank hotter and set to mix then your hot water would last longer. I.e if you had a 10l tank but set it 50% hotter than you wanted and set the mixer to 50% would you effectively end up with 15l of water at the desired temp?
 
Is the flow directly proportional to the temperature of the water, i.e. when the water is set to freezing is it coming out of the outlets at mains flow?

If so can you turn it until the flow is the optimal balance of fast and hot? Gravity hot water is always awful, should be better at the downstairs taps though...is it?
 
If the flow from all taps is poor then I can only presume there is a blockage around the tank area.

Reminds me of this video:


( http://youtu.be/SV2vdGPLRiY?t=25s )

P.S. Love how the bloke in the video axe chops towards his legs!

EDIT - Does my embedded link work for anybody? White screen for me. Link added.
 
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garak112 said:
Would this help you have hot water for longer? If you set it fully open and set your desired temp on the thermostat you will have the capacity of the tanks worth of hot water.

If you have the tank hotter and set to mix then your hot water would last longer. I.e if you had a 10l tank but set it 50% hotter than you wanted and set the mixer to 50% would you effectively end up with 15l of water at the desired temp?
Click to expand...

Oh that is a very good point, i guess this is a design feature. Sadly my hot flow isnt good enough at the moment to turn the mixer down at all :D

Participant said:
Is the flow directly proportional to the temperature of the water, i.e. when the water is set to freezing is it coming out of the outlets at mains flow?

If so can you turn it until the flow is the optimal balance of fast and hot? Gravity hot water is always awful, should be better at the downstairs taps though...is it?
Click to expand...

Its not a gravity system, its pressurised with the cold incomer, so in theory its all at the same pressure all of the time. If i turn off the cold mains to the house the hot also stops at the same time. The tank is also only on the 1st floor, it flows both up a floor to the 2nd floor and down a floor to the ground floor at the same pressure from the tank :)

But yeah the flow right now is directly proportional like you say, if i turn it right down i get the expected mains cold pressure from the hot taps. This is what leads me to think there has to be a partial blockage stopping hot water hitting the hot side of the tank mixer at full flow? The tank itself is at mains pressure, so both hot and cold at the mixer should in theory be identical.

Does my diagnosis make sense? :D
 
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Tesla said:
If the flow from all taps is poor then I can only presume there is a blockage around the tank area.
.
Click to expand...

Got to be this surely? My water is pretty hard so i do get scale everywhere, and my tank is set to the hottest temp possible.

See my theory about a blockage from the pressurised tank to the tank mixer, it has to be this surely? Nothing else makes sense. The blockage cannot be after the mixer or in any other pipework, as turning it to full cold i get full cold pressure from the hot taps.
 
My next question

How do i drain this tank? The drain valve at the bottom doesnt release any water, i am guessing this is due to me turning off the mains and there being no way for air to get into the tank?

Or something?

I really want to change the immersion heater element as it looks ancient and is bound to go soon, and i want to take that bit of pipe off to the mixer to see if it is blocked.
 
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