Please help me understand the central heating :)

[RoseofSharon1]

Hello everyone,

I hope someone can help

. Recently the old central heating programmer started behaving erratically (turning itself on and off) and was disconnected by an engineer. We wanted to buy a replacement but were not told which to get...However, we still have hot water (all the time and cannot turn it off, even before the timer was disconnected) but have no heating? Does anyone know how this system works?? And how to make it work efficiently??! Another thing is that every so often, I hear water running through the pipes as if its going to fill the water cylinder? This never used to happen so frequently before.

Set Up
1. Gas boiler
2. Water cylinder upstairs
3. No room thermostats
4. Sunvic 207 CH programmer/timer (disconnected)

Will buying a new timer make the radiators come back on? Is it one size fits all? Can I fit it myself? And would you happen to know why the hot water is always hot regardless of programmer settings?

Thank you so much everyone!

 

[EAST61]

It might be better to ask the engineer that disconnected your programmer, as it's going to be pretty much impossible for us to help you from the information you've supplied.

 

[RoseofSharon1]

Hello east 61, thank you for your reply. I can give you any other information you require. I can also take the programmer out and take pictures of the wiring if it will help, I have done it before to change the backup battery. I have tried to ask the engineer for an update but nothing so far so I've just decided to move on because it's getting so cold...

 

[EAST61]

Perhaps you could post some pictures of your boiler, surrounding pipework, motorised valves if applicable, plus any controls such as thermostats and programmers.

 

[flameport]

The programmer is what controls the system - if it's been disconnected then it won't work. You need a new one.
I don't understand why you had someone just remove it - replacing it would have been a quick and simple job.

If the hot water was always on before and still is, that is a separate problem.
Either it's been wired incorrectly so the the boiler is always on, or you have an electric immersion heater which is switched on, wasting vast amounts of electricity.

 

[RoseofSharon1]

Thank you for the replies, much appreciated.

The immersion heater is definitely off, the switch in the cupboard is off

The engineer (an electrician who works with a plumber) said the programmer wasn't wired correctly and so for safety he was disconnecting it so that the boiler bypassed it. I asked repeatedly which one to buy but he hasn't updated me. I have some pics of the programmer and the wiring

 

[gasbanni]

The programmer is what controls the system - if it's been disconnected then it won't work. You need a new one.
I don't understand why you had someone just remove it - replacing it would have been a quick and simple job.

If the hot water was always on before and still is, that is a separate problem.
Either it's been wired incorrectly so the the boiler is always on, or you have an electric immersion heater which is switched on, wasting vast amounts of electricity.

True that you wouldn't believe how mant times you see it.

Original poster for any answers more info is needed as said by others.

 

[RoseofSharon1]

True that you wouldn't believe how mant times you see it.

Original poster for any answers more info is needed as said by others.

Thank you gasbanni, I thought the same but when the hot water continued I wondered why. I thought both would stop.

Forgive me I'm a little new to this, please let me know what additional information is required

 

[RoseofSharon1]

I have uploaded some pics of the programmer backplate. Do these come as standard fit?, can I buy any standard two channel programmer and slot it on? Thank you

 

[Madrab]

Weird why he has removed the programmer stating it was wired incorrectly. It certainly seems to be wired for CH and HW control.

Without seeing it back at the boiler/wiring centre it's impossible to be sure how it's wired and hard to confirm if a standard programmer will be suitable as it stands. Back plate look universal though.

Better to get someone in to check and fit a new one for you.

 

[stem]

I have uploaded some pics of the programmer backplate. Do these come as standard fit?, can I buy any standard two channel programmer and slot it on? Thank you

Yes it's a standard backplate. But not all programmers use the same terminals for the same function. Having said that, yours is by far the most common format with terminal (3) for 'Hot Water On' and terminal (4) for 'Central Heating On' just make sure that you buy one that has the same configuration.

If you take your existing programmer to a reputable plumbers merchant and show them the diagram on the back as per your second photo, they will help you select one with the same format.

You say it's been disconnected! However, I can't see any disconnected wires at the programmer. So you will also need to find out where and how it has been disconnected.

 

[RoseofSharon1]

Thank you madrab and stem, much appreciated.

I bought a Drayton universal programmer today and hopefully it will do the job. I looked at the diagrams and they matched so I went for it.

Do I need a plumber or electrician to install it? I'm not so sure about calling out the original gentleman...
Ooh! And how much should I be looking to pay roughly? (north london)

 

[AGAS]

 

[Terrywookfit]

£ 84 any one.

 

[RoseofSharon1]

£ 84 any one.

Literally twice the price of the programmer looool