Advice on replacing Central Heating Room Thermostat

[solorize]

Hi,

I would like to replace my existing manual room thermostat which is a “Danfoss Randal RMT 230”,
but could do with a bit of advice.

Due to the current location of the existing unit, tight up against my sitting room door! I could do with
a bit of advice on which model I should replace it with and which would work with the current wiring
(which is shown in the images below).

Due to the location, as said above, is next to a door and in close proximity to my TV unit,
would I be better to go for a wireless unit? (price dependent).

I would preferably like to go for a electronic 7 Day programmable room thermostat.
Also, the hole in the wall that the existing unit fixes badly into, is 80 x 80mm so would the new unit
would need to cover this up, but still be able to fix onto the wall, I may have to turn the new one
90 degrees (i.e. mount it vertically) so that it can cover up the hole.

Please note I will be attempting to install the unit myself, so needs to be simple =)

Also is there anything else I will need to look out for i.e. matching voltages etc..? and would my
type/make of boiler make any difference in which one I should go for?

FYI.
My boiler is: Glow-worm Ultimate 50 FF Non-Condensing Gas Conventional (Regular) boiler

I would be willing to spend approx £100 max on the new unit.

Any advice would be greatly appreciated.

Images of current unit:

Current wiring

Wiring diagram

overview of location

Boiler:Glow-worm Ultimate 50 FF Non-Condensing Gas Conventional (Regular) boiler

 

[Agile]

Why has the boiler's serial number been blotted out?

Has it been stolen?

 

[solorize]

LOL, No the boiler is not stolen.

It's just out of habit for when posting images online.
I always blank serial numbers out (in image editing software),
it's not actually blanked out on the boiler plate.

Do you need to know the serial number?

 

[45yearsagasman]

The serial No is irrelevant.

 

[simond]

I assume you mean you have a single gang flush metal box behind?

Replace it with a Honeywell CM907. Use the right hand hole for the far right screw in the cm907 and reuse the m3.5 fixing screw.

You will need to drill a hole to secure the left hand side of the unit.

Make off the blue wire safely into a loose connector block and park in the metal backbox. Connect the red and yellow to the CM907 terminals A & B.

I could have done it quicker than writing this - but then we do install about 4 a week.

 

[Gavin77]

For that sort of money you have a huge choice in thermostats.

Another option that you may want to consider is an internet enabled thermostat. OK it's a little more than your budget, but it will do everything you want + a whole lot more.
Here is one from Inspire Home Automation.
http://www.ebay.co.uk/itm/180998849450?var=&ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649

Note. I was on the design team for this so i may have a slightly biased opinion, but that does mean I can answer any questions you may have.