Changing old timeclock on c.heating at home

[Thourgood]

Basically our old timeclock has gone faulty and I've sourced a set3e to replace it (it's a Y-plan). All I'm a bit unsure of is the connections, there's 2 twins and a 3 core coming into the timeclock.

Old connections are:

L - 2 reds from twins

N - 2 blacks from twins

1 - Red from 3 core

2 - spare way

3 - Yellow from 3 core

4 - Blue from 3 core

New connections in danfoss set3e are:

L -

N -

1 -

2 -

3 -

4 -

5 -

6 -

I know it's not much to go off without a drawing but I'm sure someone can help, Im sure there needs to be some links put in but I'm unsure.

Any help is much appreciated.

 

[Evans Electric]

If you don't have one with the new TS ask at a Plumbcentre type place for a replacement chart. The backplates are normally the common British Gas ones and moving the odd wire or link does the job .

The chart gives you the connections /links for most common replacements.

 

[SPECIAL LOCATION]

The new timeclocks normally have a comparison connections table or drawing with the instructions..

something like this...

http://danfoss-randall.co.uk/PCMPDF/SET2E SET3E SET3M.pdf

Just match up the switching pairs that same as you old timeclock..

there will be one make & one changeover contact in use.

 

[Thourgood]

That bottom diagram is the exact one I have. I understand linking L-2-5 but how do I establish which colour of the 3 core goes to 1 3 4 6?

 

[Sharpend]

What make/model is your old time clock?

 

[Thourgood]

It's a grasslin towerchron dp72. About 20 years old or more

 

[monkey5]

what make was the old one?

normally on the inside it will say which terminal does what. you'll probably only need two of the three cores for new time clock.

 

[steptoe]

what was your old timeclock?

sounds like a HW on

HW off

CH on

CH off type of backplate to me, (on the old clock,

so we just have to establish what connection was what on your old timeclock,

prob be connections 1 4 6 on the new clock (maybe)

---------- Post Auto-Merged at 22:14 ---------- Previous post was made at 22:12 ----------

KK

most likely term 1 was hot water off

2 spare (CH off)

3 HW on

4 CH on

so you need to know what each terminal on your new clock is, then transpose the colours across

 

[Sharpend]

what make was the old one?normally on the inside it will say which terminal does what. you'll probably only need two of the three cores for new time clock.

Y plan will need the three cores.

 

[monkey5]

yellow to 1, blue to 4, red to 3.

---------- Post Auto-Merged at 22:17 ---------- Previous post was made at 22:16 ----------

correct missed the y plan bit.

 

[Thourgood]

I thought it would be 1 4 and 6. Doesn't say on old backplate which is which. I'd assume from my first post that

1 is red (hot water N/O)

3 has nothing in it? (where hot water N/C is on diagram)

4 is yellow (heating N/O)

6 is blue (heating N/C)

 

[steptoe]

Y plan will need the three cores.

to work properly , yes,

although it can be configured to work with only 2 its a bit of a botch for existing systems with only 2 cores available.

 

[Sharpend]

You could try these for a direct replacement Grasslin Towerchron QE2 Programmer: Heating Controls Online

 

[steptoe]

I thought it would be 1 4 and 6. Doesn't say on old backplate which is which. I'd assume from my first post that 1 is red (hot water N/O)

3 has nothing in it? (where hot water N/C is on diagram)

4 is yellow (heating N/O)

6 is blue (heating N/C)

OLD CLOCK

1 is hot water off

3 is hot water on

4 is central heating on

what are the new terminals marked as?

 

[monkey5]

i was going on specs link for new clock. is that the new one?

 

[steptoe]

no,

old clock 1 = new clock 3

OC 3 = NC 1

OC 4 = NC 4

---------- Post Auto-Merged at 22:31 ---------- Previous post was made at 22:29 ----------

Basically our old timeclock has gone faulty and I've sourced a set3e to replace it (it's a Y-plan). All I'm a bit unsure of is the connections, there's 2 twins and a 3 core coming into the timeclock. Old connections are:

L - 2 reds from twins

N - 2 blacks from twins

1 - Red from 3 core

2 - spare way

3 - Yellow from 3 core

4 - Blue from 3 core

New connections in danfoss set3e are:

L -

N -

1 -YELLOW

2 -link to L

3 -RED

4 -BLUE

5 -link to L

6 -NOT USED

I know it's not much to go off without a drawing but I'm sure someone can help, Im sure there needs to be some links put in but I'm unsure.

Any help is much appreciated.

does that make sense?

 

[monkey5]

no,old clock 1 = new clock 3

OC 3 = NC 1

OC 4 = NC 4

---------- Post Auto-Merged at 22:31 ---------- Previous post was made at 22:29 ----------

does that make sense?

thats what i said, i think, gonna just check.

 

[Sharpend]

to work properly , yes, although it can be configured to work with only 2 its a bit of a botch for existing systems with only 2 cores available.

Sorry can you explain this terminology you use 'botch' I can't say that I understand this as professional term:|

 

[Thourgood]

OLD CLOCK1 is hot water off

3 is hot water on

4 is central heating on

what are the new terminals marked as?

New terminals are:

1 hot water on

3 hot water off

4 heating on

6 heating off

2 and 5 being where my permanent links go from the L terminal.

I think I should be able to work it out now, so the heating side doesn't need a connection in the off position?

---------- Post Auto-Merged at 07:21 ---------- Previous post was made at 07:10 ----------

1 -YELLOW

2 -link to L

3 -RED

4 -BLUE

5 -link to L

6 -NOT USED

I'm gonna go with that. It looks right and a few of you have backed it up so I'll give it a bash tonight.

Cheers everyone much appreciated

 

[SPECIAL LOCATION]

New terminals are:1 hot water on

3 hot water off

4 heating on

6 heating off

2 and 5 being where my permanent links go from the L terminal.

I think I should be able to work it out now, so the heating side doesn't need a connection in the off position?

---------- Post Auto-Merged at 07:21 ---------- Previous post was made at 07:10 ----------

1 -YELLOW

2 -link to L

3 -RED

4 -BLUE

5 -link to L

6 -NOT USED

I'm gonna go with that. It looks right and a few of you have backed it up so I'll give it a bash tonight.

Cheers everyone much appreciated

You are correct the heating doesn't need an off. The Y plan system uses a three port valve.

'Hot water ON' is the default position with the valve unoperated...

So the hot water on signal goes direct to the boiler via a thermostat

'Central heating ON' signal can only drive the valve to the mid point to allow water & heating to heat up

'Hot water OFF' is a voltage to help drive the valve fully over to only heat up the radiators once the water is hot or not required.

You suggested wiring connections can be confirmed by looking at the Honeywell guide..

From here....

Useful Documents - Honeywell UK Heating Controls

download the Honeywell wiring guide..

Go to page 17 it has a table of common programmers wiring connections...

third from the bottom is your old grasslin..

Hot Water Off is '1' (your Red wire)

Hot Water On is '3' (your Yellow wire)

Heating On is '4' (your Blue wire)

From the new wiring drawing..

http://danfoss-randall.co.uk/PCMPDF/SET2E SET3E SET3M.pdf

1 & 3 are reversed.. so

Hot Water Off is '3' (Needs to be Red)

Hot Water On is '1' (Needs to be Yellow)

Heating On is '4' (Needs to be Blue)