RWB9 Connection issues to Potterton Suprima HE

[D_Hailsham]

All wires are black, but they are numbered 1-4.

Thanks for the pic, but it does not help much when all the wires are black!

The second terminal from the top is the main Neutral connection. If there are any black wires going into that from the programmer, they should be connected to the N terminal on the programmer. Check by the numbers; there may not be any.

The third terminal from the top has two grey wires, these should be going to the two motorized valves. If they are, the black wires should be connected to the L terminal in the programmer

The white cable coming in from the right is the cylinder stat.

There are two white wires! The top one is labelled "heating" and, I guess, goes to the motorized valve. I presume you mean the bottom one!

This looks like a normal 2 core + earth. Check which terminals they go to in the box. One of them should have a black wire connected to the same terminal. This black wire should be connected to terminal 3 on the programmer

You should have one black wire over. This should be connected at the box to the brown wire from the heating valve. If it is, it connects to terminal 4 on the programmer.

I'm considering a room stat

What boiler (make and model) do you have?

Edit: Stupid question ! It's in the title

 

[Grahamjl]

D_Hailsham,

Have now puchased a room stat to add to the confusion. With this in mind, and the picture of my connector box, can you work out what I need to do ?

Regards

Graham

 

[baxpoti]

For the boiler to operate correctly it requires a four wire connection - permanent live, neutral, earth and switched live.

For the pump to operate correctly it must be wired back to the 'Pump' section of the boiler terminal block.

 

[D_Hailsham]

Have now purchased a room stat to add to the confusion. With this in mind, and the picture of my connector box, can you work out what I need to do ?

The simple answer is: NO

You need to read through my previous post and carry out all the checks and instructions I have given there, and let me know the results, before we can proceed any further.

As to the new room stat, which make/model have you purchased? This will determine how it is wired in

 

[Grahamjl]

D_Hailsham

Thanks for reply. Have carried out you're instructions, but to no avail !

When I turn mains on to programmer pump starts running evan when HW & CH are off

In HW only rads come on.
In CH only rads come on.

Can't tell if hot water works as emersion had been on.

Both valves are switching on and off via the programmer as I checked voltage on their corrsponding brown wires in the box.

Oh dear what have I done ?

Connections in box are as follows, starting at the top first;

Earth
10 = Neutral with a black wire going to N on programmer
9 = 2 x grey HW & CH valves - 1x wire to L in programmer 1 x to boiler
8 = 2 x orange HW & CH valves - 1 x wire to boiler
7 = 1 x brown to HW valve - 1 x blue wire to cylinder stat
6 = 1 x brown to cylinder stat - 1 wire to terminal 3 on programmer
5 = 1 x brown to CH valve - 1 x black to terminal 4 on programmer
4 = 1 x brown to pump - 1 x wire to boiler
3 = not used
2 = not used
1 = not used

What have I done wrong ?

Regards

Graham

 

[twgas]

what is programmer number 2 connected to?

 

[Grahamjl]

Mick,

Only have wires connected to terminals 3 & 4 HW and CH on. I understand that terminals 1 & 2 are HW and CH off.

Regards

Graham

 

[D_Hailsham]

what is programmer number 2 connected to?

The OP has a S-plan CH OFF and HW OFF are not required.

 

[D_Hailsham]

Thanks for reply. Have carried out you're instructions, but to no avail !

I can find nothing wrong with the wiring you gave , so there must be something else wrong.

Both valves are switching on and off via the programmer as I checked voltage on their corrsponding brown wires in the box.

That shows the valve motors are working and closing the switches in the valves

When I turn mains on to programmer pump starts running evan when HW & CH are off

The pump is controlled by the boiler. Does the pump run continuously when the power is turned on or does it eventually stop?

Quote from Manual

The boiler is fitted with a timed pump overrun that will operate for around 2 minutes after boiler shutdown.
The boiler control will operate the pump for around 2 minutes every 24 hours to maintain free running of the pump

In HW only rads come on.
In CH only rads come on.

This suggests that the CH valve is not closing the CH circuit, even though the motor is operating the switch.

Turn off the CH and remove the cover from the CH valve; the lever on the side should be in the Auto position. When you move the lever to open the valve there should be pressure as you are opening against a spring. If the lever moves easily and you feel no pressure, the valve is stuck open.

You may be able to free the valve by tapping the body of the valve with a hammer and exercising the lever.

 

[twgas]

what is programmer number 2 connected to?

The OP has a S-plan CH OFF and HW OFF are not required.

I know that but, from an earlier post;

I have used four wires in the back of the programmer (excluding the live and nuetral). One attached to neutral, one on 2, 3, & 4

 

[D_Hailsham]

I know that but, from an earlier post;

I have used four wires in the back of the programmer (excluding the live and nuetral). One attached to neutral, one on 2, 3, & 4

That was a very early post you quoted from! Things have moved on since then and I presumed you had read the later posts.

 

[twgas]

I did, but what happened to that wire?

 

[D_Hailsham]

I did, but what happened to that wire?

Presumably the OP followed my instructions in the post dated Sat May 03, 2008 11:04 am, at least that what I read from his post on Thu May 08, 2008 9:37 pm.

Thanks for reply. Have carried out you're instructions, but to no avail

This would have meant no wires on terminals 1 or 2

 

[Grahamjl]

D_Hailsham

"This suggests that the CH valve is not closing the CH circuit, even though the motor is operating the switch.

Turn off the CH and remove the cover from the CH valve; the lever on the side should be in the Auto position. When you move the lever to open the valve there should be pressure as you are opening against a spring. If the lever moves easily and you feel no pressure, the valve is stuck open. "

You could have something here, please see my latest photo!

I removed the CH valve body, and as I did the mechanism finished closing. Upon closer inspection I noticed although the electrical side is working the mechanical "tap" had seized in a half open/half closed position.

I understand now why in HW only mode my rads warm up.

My question now is; If this is left in this position is this why the pump continues to run when programmer is off ?

Thanks for all your help so far. I'll try to free up the valve, and post my results before we look at the wiring again.

Regards

Graham

 

[D_Hailsham]

You could have something here, please see my latest photo!

Where's the photo?

I removed the CH valve body, and as I did the mechanism finished closing. Upon closer inspection I noticed although the electrical side is working the mechanical "tap" had seized in a half open/half closed position.

What I thought
Just to be pedantic, what you removed is called the actuator, the body is the T shaped brass part which contains the "tap".

My question now is; If this is left in this position is this why the pump continues to run when programmer is off ?

I have not had an answer to this question:

Does the pump run continuously when the power is turned on or does it eventually stop?

If it stops after a few minutes, that's OK; but, if it never stops, read on!

"power turned on" presumably means at the main switch, not when the programmer is set to CH or HW on. Am I right?

You have not shown where the main electrical supply comes from. Is there a wall switch or fused spur near the boiler or is it near the junction box? I suspect it is near the boiler as the wiring you provided gave the following:

9 = 2 x grey HW & CH valves - 1x wire to L in programmer 1 x to boiler
4 = 1 x brown to pump - 1 x wire to boiler

The wire from 9 to the boiler is probably the live feed from the boiler to the junction box. This provides power to the programmer and to the two grey wires, which is correct. You can check by temporarily disconnecting it and seeing if the programmer still works.

The wire from the boiler to 4 and then to the pump is the supply from the boiler to the pump, which is also correct.

You will see from this that the pump is not controlled by the programmer but by the boiler.

The next thing to check are the connections at the boiler. The pump should be fed from terminals marked PUMP. only the L terminal will be used as the N and E connections are made near the pump. If the PUMP L terminal is connected, temporarily disconnect it and check that the pump stops.

If the pump never stops there is something wrong with the timer on the circuit board. This means a new board.

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