Heating Controls / Wiring / Independent Central Heating

[sgreenwood1]

Hi - first time poster, long time lurker! Have used this fori extensively recently for several diy guides, so thank you.

Currently I can only establish central heating in the house if I enable hot water. (I can have hot water without heating).

Initially, as it's an old house, I thought this was a limitation of my heating system (thinking it was semi-gravity / gravity fed).

However, after some recent reading up on the subject I have established that the system may have been converted by the previous owner when a Worcester Greentar RI boiler was installed in 2012.

The airing cupboard has a pump and a (new) mid position valve (receipt for March 2014 found in the house paperwork _ I moved in in November)).

The house has a British Gas 'Hive' receiver installed (not registered it) which can be used as an in-house heating controller if unregistered (I confirmed this with BG).

I beleive this to be wired incorrectly and have attached photo's of the set up behind the timer and behind the junction box in the airing cupboard along with the pump and mid position valve. I've also shown the wiring guide behind the Hive programmer (receiver) - is mine wired correctly.

Can anyone suggest some wiring 'fixes' that could be carried out by me to enable independent CH control?

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• sgreenwood1
• 20 Dec 2014
• 1

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• sgreenwood1
• 20 Dec 2014
• 1

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• sgreenwood1
• 20 Dec 2014
• 1

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• sgreenwood1
• 20 Dec 2014
• 1

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• sgreenwood1
• 20 Dec 2014
• 1

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• sgreenwood1
• 20 Dec 2014
• 1

 

[AndyPRK]

Is the grey cable on the left to the hive?

 

[sgreenwood1]

Is the grey cable on the left to the hive?

If the labels on the junction box in the airing cupboard actually mean something then I would assume it's the third grey wore from the left (if that's the photo your referring to?).

 

[flameport]

Wiring is wrong, as there should be a wire connected to terminal 1 in the programmer, which is what sets the hot water to off, allowing heating only.

However there could be other problems as well, so just adding that wire may not be the solution.

 

[ericmark]

I have not traced the wiring but my daughter had a similar problem it turned out that the motorised valve micro switches were faulty and previous owner had latched the valve manually to mid position it is to allow bleeding but it had been left that way.

My son-in-law was tidying up the airing cupboard and he caught the latching leaver which resulted in central heating failure but still hot water. Latching the leaver again got it working but this resulted in the summer the radiators still got hot.

So as a quick fix try latching the manual leaver will need fixing by the summer but may give you heating in the mean time.

 

[Lectrician]

You need to ensure you have an off signal from both the time clock and the cyl stat. And then make sure programmer is set pumped, not gravity.

 

[sgreenwood1]

Wiring is wrong, as there should be a wire connected to terminal 1 in the programmer, which is what sets the hot water to off, allowing heating only.

However there could be other problems as well, so just adding that wire may not be the solution.

How do I add a wire to terminal 1?

Is this an easy diy job?

Can I put a link in manually behind the receiver/programmer or does it need feeding all the way from the airing cupboard?

 

[sgreenwood1]

You need to ensure you have an off signal from both the time clock and the cyl stat. And then make sure programmer is set pumped, not gravity.

The cylinder stat turns HW on/off successfully (tested by altering the dial).

Programmer is set to pumped (checked how to alter on the BG website).

It seems the HW off wire is missing behind the programmer / time clock as per above. Can I insert a link wire behind this?

 

[Lectrician]

The cyl stat still needs an off signal as well as the programmer. Are there unused cores in the cable from the programmer to the wiring center? It looks like there isn't. If not, a relay would be required.

 

[sgreenwood1]

The cyl stat still needs an off signal as well as the programmer. Are there unused cores in the cable from the programmer to the wiring center? It looks like there isn't. If not, a relay would be required.

I will double check later but from memory and from zooming in on photo, I don't think so... I assume without any unused cores then it can't be done?

 

[AndyPRK]

Wiring is wrong, as there should be a wire connected to terminal 1 in the programmer, which is what sets the hot water to off, allowing heating only.

Good point!

A wire between the timer (1) and blue wiring center (7).


Its odd, because Two 3 Core and earth cables (red/blue/yellow) leave the blue box. But none appear at the timer.

A picture of the hive wiring would be interesting.

 

[flameport]

You need another core at the programmer - however if this is the Hive receiver, it can be positioned anywhere, as the actual control panel/thermostat is wireless.

Therefore probably simpler to relocate the Hive receiver next to the wiring centre, and redo that mess of wiring inside it at the same time.

 

[AndyPRK]

Oh rite. The timers gone is it. The white thing is the hive ?

 

[sgreenwood1]

Oh rite. The timers gone is it. The white thing is the hive ?

The Hive has three parts- a wireless thermostat / controller for the CH and Hw; a receiver (situated where the time clock used to be and photod previously) and a hub which connects to the internet.

The 'missing' wiring discussed is behind the receiver.

In theory this could be moved to the airing cupboard near the mass of wires pictured?

Would this be simple to wire up?

 

[flameport]

Y plan wiring is here: http://www.flameport.com/electric/central_heating/heating_wiring_Y_plan.cs4
which needs a slight alteration for the Hive, as there is no separate room thermostat.

Updated with Hive wiring diagram.