80, is the thermostat faulty? Should I adjust the temp on the thermostat or how to test if it’s faulty, any help or advice would be much appreciated thank you ( I’m assuming the setting is over 80 on the thermostat ) eg is that where the arrow pointing
Faulty water cylinder thermostat?
- Thread starter Mojo12345
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80, is the thermostat faulty? Should I adjust the temp on the thermostat or how to test if it’s faulty, any help or advice would be much appreciated thank you ( I’m assuming the setting is over 80 on the thermostat ) eg is that where the arrow pointing
This thermostat often has a white plastic knob in the middle of the "cross". However, these break off quite easily (or can be removed to stop people tampering) leaving what you have.
If you use a screwdriver to turn the thermostat knob anti-clockwise, you should be able to hear a slight click when it goes past the temperature it is actually recording. If you don't hear a click I'd suspect the thermostat is faulty, although they are usually pretty reliable. Probably the cheapest diagnosis / repair you can do yourself is to just replace it like for like. BUT remember you are dealing with mains voltages on the terminals, so turn the power to the house off at the consumer unit. Don't rely on switching off the boiler or other controls, I've seen thermostats with "borrowed" lives and neutrals. Use a multimeter to make sure there is no live voltage at the terminals. Should be able to get one for around £20 to £25.
If you use a screwdriver to turn the thermostat knob anti-clockwise, you should be able to hear a slight click when it goes past the temperature it is actually recording. If you don't hear a click I'd suspect the thermostat is faulty, although they are usually pretty reliable. Probably the cheapest diagnosis / repair you can do yourself is to just replace it like for like. BUT remember you are dealing with mains voltages on the terminals, so turn the power to the house off at the consumer unit. Don't rely on switching off the boiler or other controls, I've seen thermostats with "borrowed" lives and neutrals. Use a multimeter to make sure there is no live voltage at the terminals. Should be able to get one for around £20 to £25.
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Not to take away from the excellent advice already given (and this is the first advice I've offered on these forums so please be gentle 
)
but
To me, it looks as if that arrow (if that's what the right-angle beside the cross, is) could be pointing sort of at the 'min' setting (i.e. at the very minimum setting, rather than past the highest setting)...
... have you tried actually turning it clockwise to see if it goes to a higher setting?
)but
To me, it looks as if that arrow (if that's what the right-angle beside the cross, is) could be pointing sort of at the 'min' setting (i.e. at the very minimum setting, rather than past the highest setting)...
... have you tried actually turning it clockwise to see if it goes to a higher setting?
Hi everyone, I checked the thermostat today and left the hot water on boiler running for 2 hours the thermostat is working because it clicks but it clicks at 40 degrees not at 60 degrees the water cylinder doesn’t get that hot ? Also the pipe coming out of the top of the tank is not too hot? I’m just wondering what the problem could be? Generally the hot water around the house is only like warm and advive would be great thanks
What is the thermostat on the boiler set to? Regardless of the temperature on the hot water cylinder thermostat, it won't get any hotter than the water from the boiler supplying it.
For example: If the boiler is set to 55 degrees the hot water cylinder will never exceed that no matter how long the hot water is left on for, or what the cylinder thermostat is set to.
For example: If the boiler is set to 55 degrees the hot water cylinder will never exceed that no matter how long the hot water is left on for, or what the cylinder thermostat is set to.
The thermostat is not the problem, show us the other controls that you have, valves boiler etc so we can see your set up
As above, my money is on the stat being fine, I'll wager it's a S plan system and the HW valve is goosed. Pretty confident Mojo, that stat is on it's highest setting in the photo, turn it back to around 60-65, I dont think that is your problem. Look at the hot water cylinder, should be 2 pipes coming out the side, one above the other. On the top pipe, is there an electrical 'box' connected into the pipework? If so, can we have a picture please. 
also the water cylinder the two pipes going in are luke warm and the pipe coming out at the top is mildly warm, the boiler seems to be set at 60 degrees but I’m not sure, the pressure on the expansion tank seems between 1-2 bar,
I’ve added some pics any advise or help would be great sorry for the poor light in pics it’s difficult to take pics on the loft as space is tight
Sorry for the long post but I wanted to know
-how long should the boiler be on for to get hot water in morning and fill tank up
At the moment I have it for 1 hour is that enough or should I do it for 2?
- the cold water storage tank has no lid should I get a new lid or have the whole tank replaced it looks old and manky
- I’m not sure the water cylinder is ok? How would I test it to know it it needs replacing could it rust over time?
Thank you
-how long should the boiler be on for to get hot water in morning and fill tank up
At the moment I have it for 1 hour is that enough or should I do it for 2?
- the cold water storage tank has no lid should I get a new lid or have the whole tank replaced it looks old and manky
- I’m not sure the water cylinder is ok? How would I test it to know it it needs replacing could it rust over time?
Thank you
Its your boiler output temperature which is too low to heat the water. Boiler output temperature has to be higher than the cylinder temperature, or no heat will be transferred and the boiler will futilely burn lots of gas trying.
Insulate those pipes. You are throwing money away. If they are in an unheated area, one day they will freeze and burst.
The cylinder will not rust, it is made of copper. One day it will leak. This may take 20-50 years.
Your cold water tank must have loose-fitting lid and an insulating jacket. Clean it out while you are working. If the cold bath tap is supplied from tank (not the watermain) use it to drain the tank and while you are rinsing after cleaning.
The cylinder will not rust, it is made of copper. One day it will leak. This may take 20-50 years.
Your cold water tank must have loose-fitting lid and an insulating jacket. Clean it out while you are working. If the cold bath tap is supplied from tank (not the watermain) use it to drain the tank and while you are rinsing after cleaning.