Replacing Honeywell BDR91 Receiver with Tado Wireless Receiver

[griffen]

Hi,

Trying to replace my BDR91 with a Tado Wireless Receiver. Find a picture of my BDR91 attached.

Read a lot of different articles and believe I need to complete the following wiring.

My BDR91 doesn't appear to have a bridge between L and A. I have the following questions:
- Where does A go?
- Does the second L wire go into L or No. 2 in the Tado Wireless Receiver

Think my wiring is as follows
BDR91 – 1x Blue Wire in N
TADO – N

BDR91 - 2x Brown Wire in N
TADO – L

BDR91 – 1 x Blue Wire in B
TADO – B

Thanks for your help.

 

[stem]

Because there is no link between the BDR91 'L' and 'A' it is being used in 'Potential free' mode. If you have the TADO extension kit as per the picture below...

N&L from the BDR91 transfer to N&L exactly as they are now. The two BDR L terminals are electrically connected so effectively the same terminal.

The wires in the BDR91 A & B go to the TADO extension kit '1' and '4' and select jumper position 1 'Potential Free'

A&B and 1&4 are both simply an on/off switch as the diagrams on the units show, so they have exactly the same function.

EDIT:

I've added the diagram from the TADO manual, showing terminals 1 & 4 as the switch. If your TADO is different to this, post back details of it before proceeding.

Because you are replacing a room thermostat receiver with the TADO receiver that means it can only control the central heating, It can't give hot water control. However, if you have a combi boiler without a stored hot water system (ie a hot water cylinder) that's not going to be an issue for you.

If you do have a hot water cylinder and want to control it with TADO, then the whole way of installing it changes from the above.

 

[griffen]

Thanks Stem. I don't have a hot water cylinder. I have the middle boiler which I believe is a Vaillant ecoTec Pro 24. Does that make any difference?

Edit
Also, find attached an image of the receiver. Looks a little different to yours without the numbers. Can see the P1 though.

 

[CBW]

Thanks Stem. I don't have a hot water cylinder. I have the middle boiler which I believe is a Vaillant ecoTec Pro 24. Does that make any difference?

Edit
Also, find attached an image of the receiver. Looks a little different to yours without the numbers. Can see the P1 though.

That middle boiler is a Worcester not Vaillant. The Tado receiver you have is 2 channel and might not be suitable if you have extra low voltage on existing.

 

[griffen]

Thanks. Okay.

Gone through all of the notes and the final wiring below.

BDR91 – 1x Blue Wire in N
TADO – Supply N

BDR91 - 2x Brown Wire in L
TADO – Supply L

BDR91 - 1 x Brown Wire in A
TADO - Central Heating (CH) - COM (1)

BDR91 - 1 x Blue Wire in B
TADO - Central Heating (CH) - NO (4)

Is this correct?

Do I need to do anything with Parking P1 or P2?

 

[CBW]

No need for anything in P1 and P2. You need to check whether it’s capable of mains switching, otherwise it might cost you.

 

[griffen]

Thanks Chris. You mean the receiver? Had a look and couldn't see how you determine if it's capable of main's switching. How do you check?

Is the wiring correct?

 

[CBW]

I can only answer if the wiring is correct if the correct output is determined. Apologies, let me see if this is clearer:

The receiver for 240vac is capable of mains switching, you need to find out if the boiler is capable - only diy thing you can do is check with a multimeter. If it’s not, then you might fry the pcb.

 

[griffen]

Ahhhh....well I might have wrongly identified the boiler as it's British Gas branded. Find a picture of the boilers control panel. Also with the fuse, picture attached, would that not suggest it's capable of mains switching?

 

[stem]

Deleted

 

[CBW]

If you follow the instructions I gave you, you are swapping one potential free switch for another potential free switch.

I don’t think that’s the case mate, post #3 OP has attached an image of receiver.

 

[stem]

Quite right, my apologies I'll delete it although that has no resemblance to the photo in his original post . So, I'll delete my last post duck out and leave you to it. Too many cooks spoil the broth.

 

[CBW]

Also with the fuse, picture attached, would that not suggest it's capable of mains switching?

No, the switching is done inside the boiler. I have just checked and yours is mains switching capable. You need to confirm which receiver you have as your interchanging between them

 

[griffen]

CBW and STEM thanks for your help. Made the switch and so far...(fingers crossed)...it's working. Thanks again for your help.