Replacing a British Gas UP1 with a Smart Thermostat

[Jbswagger]

Hi,

I have a Glowworm Micron 60FF system boiler with a hot water tank. There is a British Gas UP1 programmer and RS1 thermostat. Can these easily be replaced by a Honeywell Lyric T6?

Thanks for all the replies.

 

[stem]

AFAIK the Honeywell Lyric T6, is just a smart thermostat, so unless a version that I'm not aware of has been introduced, it doesn't incorporate controls for a stored hot water system (ie a hot water cylinder)

If that is the case, then you could re-route the thermostat wires from the existing RS1 thermostat to the Honeywell Lyric T6 receiver and leave the UP1 programmer in place to control the hot water on/off times. The central heating would need to be set to be permanently 'on' 24/7 at the programmer to prevent it interfering with the operation of the Honeywell.

 

[Jajodu]

There is a new lyric that can also control the hot water as well as heating.

 

[Jbswagger]

Thanks for your reply. I'm steered towards the Lyric because it's cheaper than other ranges.

This is the first time I have looked at the smart thermostats.

Looks like Honeywell T6R-HW Wireless Smart Thermostat With Hot Water Control does?
https://theevohomeshop.co.uk/honeyw...stat-with-hot-water-control-y6h920rw4026.html

 

[stem]

Indeed there is, it's a T6R-HW

Edit
Ha! you beat me to it

 

[Jbswagger]

Is it straightforward wiring these up?

 

[Jajodu]

Yes, if you are comfortable with electrics and three port valves.

 

[stem]

Depends how skilled you are.

The T6R-HW receiver box....

....replaces the UP1 programmer

The existing wires are moved across from the UP1 to the T6R-HW receiver box terminals that have the same functions as identified from the two diagrams above. Terminals L, A & D should also be linked together.

If you do have a 3-Port motorised valve (instead of two, 2-Port valves) then you will have a wire in the 'hot water off' terminal of UP1 terminal (1) which should correspond to T6R-HW terminal (F) although it's not actually shown connected anywhere in their diagram. Maybe @Jajodu has installed one and can confirm this.

You won't have any OT (OpenTherm connections)

The existing RS1 thermostat should then be decommissioned. It can't just be disconnected otherwise the wiring will remain open circuit and the heating won't work. This is done by tracing the thermostat cable back to its origin, disconnecting the wires at source and then linking together the terminals where the thermostat live switching wires have just been removed from to complete the circuit. Alternatively the RS1 could simply be left in place and left set on its maximum setting. This will prevent it interfering with the operation of the T6R-HW.

 

[Jbswagger]

Thanks for the detailed reply Stem.

You mention leaving the RS1 in place. If possible, I was hoping to mount the new Lyric in it's place rather than mounting it in place of the UP1 or anywhere else.

Do I need to konw what type of cable is behind the RS1?

 

[stem]

You don't have to leave it in place. It's far better to remove and decommission it, and is what a pro would do. What I meant by...

Alternatively the RS1 could simply be left in place and left set on its maximum setting.

.... is that leaving it in place and on maximum is an option for DIY'ers who don't feel competent to alter the wiring to facilitate its removal.

 

[Jbswagger]

Thanks for clarifying that.

Can I use the existing RS1- UP1 cable?

 

[stem]

What for?

The TR6 thermostat plugs into the mains and communicates with the receiver wirelessly.

 

[Jbswagger]

As mentioned I'm new to the subject and hadn't relied everything was wireless. Does the receiver go where the UP1 box is now mounted?

I've looked in the airing cupboard and there are 2 x 2-port motorized valves.

 

[stem]

The existing wires from the UP1 need reconnecting to the new Honeywell receiver, so it's usually the easiest to mount it in the same place, but you can relocate the wires to a different position if you wish.

If you have 2 x 2-Port valves, that means there will be one less wire to relocate, as there won't be a wire in UP1 terminal (1), so the question about the Honeywell terminal (F) doesn't apply now.

So:
UP1 N = TR6-HW (N)
UP1 L = TR6-HW (L)
UP1 3 Hot water on = TR6-HW (E)
UP1 4 Heating on = TR6-HW (B)

Link TR6-HW (L) (A) & (D)

EDIT
Diagram added. The connections to the motorised valves and cylinder thermostat won't change from what you have now. the diagram shows the connections at the receiver that you are interested in.

 

[Jbswagger]

Thanks for the detailed reply. I'll let you know how I get on when I actually do the job.