What Time Switch - Myson Economist WM40/50BF?

[ATL11]

Hi, have this Myson Gas Boiler, and the Clock on the Time Switch has decided to stop, so need to replace, but not sure which Switch to go for?

Current Time Switch model has TR80 or TR8C logo on it, the clock can switch the Boiler on/off @ set times, HW Only, HW & H, Timed, Constant & Off. Just need to know what equivalent model can I replace it with?

Also why asking can I replace with a Myson Time Switch MEP1C or a MEP2C?

Heating is working with Constant switched on and Temp settings changed on the Thermostat in the Hallway.

Thanks

 

[D_Hailsham]

not sure which Switch to go for?

Any make will do the job, it does not have to be Myson.

Current Time Switch ... clock can switch the Boiler on/off @ set times, HW Only, HW & H, Timed, Constant & Off. Heating is working with Constant switched on and Temp settings changed on the Thermostat in the Hallway.

Just to clarify, your options are:

Hot Water only: Timed, Constant or Off
Heating and Hot Water: Timed, Constant and Off
Heating only: Constant only controlled by wall thermostat

Do you have a thermostat on the side of the HW cylinder?

Do you have any motorised valves? If so how many and which make/model They look something like this:
View media item 800 View media item 801

can I replace with a Myson Time Switch MEP1C or a MEP2C?

If you want to, but as I said you don't have to use Myson. Which one will depend on your system and the answers to my questions

 

[ATL11]

Hi,

Thanks for the feedback, and to answer your questions:

Hot Water only: Timed, Constant or Off >>> Yes
Heating and Hot Water: Timed, Constant and Off >>> Yes
Heating only: Constant only controlled by wall thermostat >>> Yes

Do you have a thermostat on the side of the HW cylinder? >>> Yes set to about 50

Do you have any motorised valves? If so how many and which make/model They look something like this: >>> Looks similar to the picture, the logo on it says 'Danfuss' and the lever looks like it can be moved to Manual 'Man' or Auto. Down the side of the white box it says 'Hot Water & Heating with corresponding arrows, which I think indicate the pipe direction, thanks[/b]

 

[ATL11]

Mr D Hailsham,

Hi, any chance you can confirm what I need to buy, thanks?

 

[D_Hailsham]

Hi, any chance you can confirm what I need to buy, thanks?

Not until you tell me which model Myson boiler you have!

 

[gas4you]

The clue is in the title I believe

 

[D_Hailsham]

The clue is in the title I believe

So it is Didn't think of looking there!

 

[D_Hailsham]

Any programmer will be suitable. If you choose a single channel one you are stuck with the same times for heating and hot water - just like your existing programmer. If you go for a two channel programmer you can set the times when the heating and hot water are on completely independent of each other.

The MEP1C is a single channel version and the MEP2C is two channel. If they use the same back panel as your old time switch, it may be possible to install a Myson programmer without disturbing the wiring.

I see that you set your HW thermostat to 50°C. This is lower than the recommended setting which is 60-65°C. The reason for this is to minimize the chances of Legionella, as explained in this extract:
It is known that the bacteria require water, warm temperatures and a food source. While the bacteria will grow at temperatures of between 20.5ºC and 50ºC, the optimal temperature range for the growth of legionella is between 35ºC and 46ºC. The legionella bacteria cannot survive in water above 55ºC for more than five or six hours and its survival in temperatures above 55ºC is shorter, depending on the temperature. Instantaneous destruction of the
bacteria occurs at a temperature of 70ºC and above.

If the water is too hot, not only is there a chance of scalding someone but the chalk in hard water will tend to get deposited on the inside of the cylinder. and on the heating coil, reducing its efficiency.

 

[ATL11]

Hi, Mr Hailsham

Thanks for the response.

Have found the MEP2C available for around £44 before delivery from BHL, is there any other companies that could be recommended?

http://www.bhl.co.uk/product.php?productid=57024&cat=8335&page=

Also have the MEP2C documents from the Web, and I take it I have to get Specialist in to fit it, as the instructions look like something from MFI...

http://www.heatyourkitchen.co.uk/img/MEP2C_Installation_Instruction.pdf

Also have changed the Temperature on the Thermostat on the HW Cylinder to 60, is that suitable?

 

[D_Hailsham]

Have found the MEP2C available for around £44 before delivery from BHL, is there any other companies that could be recommended?

I suspect the Myson is just a re-badged Drayton as Myson are essentially radiator manufacturers. So a Drayton Lifestyle LP241 (24hr), LP522 (5/2 day) or LP722 (7 day) would also do the job.

Also have the MEP2C documents from the Web, and I take it I have to get Specialist in to fit it, as the instructions look like something from MFI...

Actually they are not bad as they give info about replacing other programmers with a MEP2C.

You should not need an electrician to do the swop over, but you may need some guidance The first thing to do is to write down the connections to the existing time switch. Turn the power off and remove the time switch from its back plate, usually held in place by a screw on the underside. Then note down which terminals have wires connected. They may be numbered (1,2 etc) or labelled (L, N, CH ON etc). YOu may even find that the back plate is numbered but the programmer has a table showing what each connection does.

Post the info and you will get assistance on installing the new programmer - when we know what you have bought.

One thing which has not been confirmed is the make of the existing time switch; we have just assumed it is a Myson. Can you confirm that it does say Myson and are there any other identifying marks, apart from TR80 or TR8C?

Also have changed the Temperature on the Thermostat on the HW Cylinder to 60, is that suitable?

Yes.