New hot water cylinder thermostat - Wiring help

[sjmyles]

The water in my indirect cylinder now practically boils and having guessed that it is the thermostat at the top of the cylinder that is shot I am about to replace it with one that straps to the cylinder side.
Now wiring up is my problem.
Currently I have a switch wth cable running to my cylinder thermostat in the form red, black and green/yellow. its a satchwell therm but has no markings to provide an insight into whats what in the fixing.

I have bought an Invensys HTS3 which has a wiring chart which I cannot make head nor tail of.
It has 1 (Call for Heat) 2 (Satisfied) and Common fixings.

If I take cable from my switch which should I wire to which fixing.

Really appreciate some help here.

Thanks
Simon

 

[oilman]

Use the CALL FOR HEAT terminal.

 

[sjmyles]

Currently at the thermostat on the boiler I have three wires going in to it which travel from an on / off switch on the wall. These three wires connect at the switch to red, black and green/yellow.

So for my new thermostat I'm confused about which I should connect to : I have a new 3 core cable which I connect at the switch one each to red, black and green/yellow - this cable then must connect to my thermostat - I have 1,2 and common.

What I'm trying to work out is should it be red to 1 black to 2 and green/yellow to common - or one of the other combinations.

Appreciate your help.

 

[salem2000]

Currently at the thermostat on the boiler I have three wires going in to it which travel from an on / off switch on the wall.

So for my new thermostat I'm confused about which I should connect to

I would ask myself "why would a thermostat be connected to an ON/OFF on the wall". Are you confusing the heating element with a thermostat. If your not sure GET ADVICE, NOW.

 

[oilman]

Thanks salem2000, I hadn't really cottoned to what was going on. You are probably spot on about the heating element.

Sjmyles, I suggest you take salem2000's advice and get someone to look at. You should have a new immersion heater stat fitted and this MUST be a non-self resetting type, this is a legal requirement since last month.

DO NOT ATTEMPT TO CONNECT ANY OTHER STAT TO THE TERMINALS ON THE TOP OF THE TANK, it may be terminal for you!!!

 

[salem2000]

oilman, It wasn't till I read the post a couple of times myself that I noticed the "Switch". It just goes to show how easily things go wrong.

Just hope "sjmyles" got the post.

 

[sjmyles]

thanks

 

[mngray]

My water is very hot too. The cylinder is a factory insulated one, with an immersion. I can follow the immersion wires to the power switch in the wall. I do not know when the cylinder was installed. I have the impression that there is no thermostat (I cannot see one at all). Is this likely, or am I just blind? I assume if it is there it could be either surface or internally mounted, but certainly it is not obvious. presumably wires then run from it down to my CH/HW programmer. I did put in a new programmer recently and saw no wires for the cylinder thermostat, although there are wires for the room thermostat in the hallway. My questions really are: could there really be no thermostat? If so can I fit one (surface mounted) and run the wires down to the programmer?

Help!

Mark

 

[ArtfulBodger]

My water is very hot too. The cylinder is a factory insulated one, with an immersion. I can follow the immersion wires to the power switch in the wall. I do not know when the cylinder was installed. I have the impression that there is no thermostat (I cannot see one at all). Is this likely, or am I just blind? I assume if it is there it could be either surface or internally mounted, but certainly it is not obvious. presumably wires then run from it down to my CH/HW programmer. I did put in a new programmer recently and saw no wires for the cylinder thermostat, although there are wires for the room thermostat in the hallway. My questions really are: could there really be no thermostat? If so can I fit one (surface mounted) and run the wires down to the programmer?

Help!

Mark

Turn the switch off & take the immersion heater cover off & all will be revealed. There is no connection between the immersion heater & the central heating controller.

The question you should be asking yourself though is: "if I have a boiler why the hell have I got the immersion heater on?"

 

[parlour]

Currently at the thermostat on the boiler I have three wires going in to it which travel from an on / off switch on the wall. These three wires connect at the switch to red, black and green/yellow.

So for my new thermostat I'm confused about which I should connect to : I have a new 3 core cable which I connect at the switch one each to red, black and green/yellow - this cable then must connect to my thermostat - I have 1,2 and common.

What I'm trying to work out is should it be red to 1 black to 2 and green/yellow to common - or one of the other combinations.

Appreciate your help.

 

[kevindgas]

Turn the switch off & take the immersion heater cover off & all will be revealed. There is no connection between the immersion heater & the central heating controller.

The question you should be asking yourself though is: "if I have a boiler why the hell have I got the immersion heater on?"

The electric element in the top is just that, an electric element with a thermostat inside a pocket.

the cylinder thermostat 1/3 way up is the Central heating boiler's water temperature thermostat. works in conjuntion with room thermostat and diverter valve.
if you are using your boiler, you must not use the electric one at the same time
as it will overheat the cylinder.

 

[gas4you]

This post was nearly 4 1/2 years ago

 

[kevindgas]

probably burnt out by now