Replacing Fused Boiler Switch with Wemo Socket

[bryso1234]

Hi there,

I have a Baxi Solo Gas boiler in an upstairs hotpress, which is turned on and off via an electrical timer switch. The electrical timer switch is connected via a fused socket, also in the hot press.

What I would like to do is to not use the existing electrical timer switch at all and hook up the Wemo so I can set the timer via a schedule, or remotely.

http://www.belkin.com/uk/F7C027-Belkin/p/P-F7C027/

As the Wemo is not compatible with the faceplate for the existing timer switch, what I was going to do was to replace the Fused Boiler switch with a standard UK 3 plug faceplate, plug in the Wemo and then connect the existing timer switch to the wemo via a newly wired plug (matching fuse of current switch). This would effectively connecting the 2 switches in series.

Is there any potential issue with doing this?

 

[EFLImpudence]

If I have understood correctly; it's quite likely I have not -

What I would like to do is to not use the existing electrical timer switch at all

plug in the Wemo and then connect the existing timer switch to the wemo

Contradiction?

via a newly wired plug (matching fuse of current switch). This would effectively connecting the 2 switches in series.

Is there any potential issue with doing this?

Yes, neither will work when the other is off and ...

when the Wemo is off the timer clock will stop.

 

[bryso1234]

Yes sorry, it's a slight contradiction. I mean that the existing timer switch will be always on - I won't disconnect it, but will effectively not use it in practice.

What I'm wondering is, is this ok from an electrical point of view. Is there any reason that a boiler has to be connected via a fused switch as opposed to a standard plug?

 

[AndyPRK]

The boiler in my house is live all the time to allow the fan to cool it after its shut down.

The timer is connected via the boiler.
Yours isn't like that is it ?

 

[ericmark]

The only question is the boiler. Some boilers simply switch on and off by giving or removing power but most modern boilers have power to them all the time and when there is no demand the pumps can still operate in order to cool down.

Although some may use 230vac other use just 24 volt for the control circuits so what ever controls them needs to have volt free contacts.

You may need to use a 230vac relay to get volt free contacts for this to work.

Also remember in the UK we use TRV's to control our heating so each room is independently controlled. The boilers vary but some are really clever and they alter output by monitoring the return water temperature and also switch off and on with a varying time dependent on the speed at which water warms up.

Any timer or thermostat can upset the automation of the boiler. Unfortunately the boiler firms often only release the circuit diagrams to registered gas fitters so unlike most items it's hard to find exactly what each boiler does or requires.

Often there is a link which can be removed for timer or thermostat but the thermostat is for outside not inside so the boiler does not kick in when it is likely to be a warm day.

There are WiFi TRV's so you can control each room oddly there does not seem to be a hard wired version. It would seem you simply replace the head of the TRV my son is considering the idea so bedrooms not heated in the day and living rooms not heated at night.

 

[PrenticeBoyofDerry]

I would suggest reading the manufacturers instruction, regarding whether it is acceptable to use a socket outlet opposed to a FCU.

 

[ericmark]

I think this is the installation guide which states page 14 "This boiler does not require a permanent live." So it seems your idea will work.

But do read yourself and make sure I have found the instructions for your boiler before going ahead.

 

[bryso1234]

Thanks folks.

The switch is a Horstmann channelplus H17XL

http://www.horstmann.co.uk/files/1113/9867/2127/user_guide_H17XL-USeries21.pdf

Picture of setup is
https://dl.dropboxusercontent.com/u/4744306/SWITCHES.jpg


This is the manual for my boiler

http://www.baximarketing.co.uk/disc...only-boilers/5106726-08-Install-Solo3-PFL.pdf

The manual does mention this on page 30.
4. The pump must be connected to the boiler terminals.
5. A permanent live must be connected to the 'L'
terminal.
6. The switched live must be connected to the 'S/L'
terminal.

Is this bad news for my plan?

 

[AndyPRK]

Yes it's bad news.

What are you tying to achieve ?

 

[bryso1234]

Darn. Ultimately trying to achieve being able to turn on/off central heating from my phone or remotely without spending the earth, so I thought the wemo would fit the bill.

Is there any other way I could hook the wemo up? At the minute, it's only available in this format

http://www.belkin.com/uk/F7C027-Belkin/p/P-F7C027;jsessionid=EFE49BFAF2C1D3FFD88FD05F3FF67680/

 

[EFLImpudence]

You could wire another socket from the FCU.
Plug in the Wemo.
Connect the Wemo switched live out to the timer switched live terminal.

I.e. wired in parallel bypassing the timer.

It does seem to be a solution to a problem which does not exist.
How cold is the house when you come home unexpectedly and how often?



Also, it seems an odd set up.
Out of interest, how is your water heated?

 

[EFLImpudence]

I.e. wired in parallel bypassing the timer.

Just realised that would not be a good idea because when the timer was on the plug could be pulled out and would be live.

You would have to use a relay.

 

[AndyPRK]

What's the primary goal ?

To override the heating on remotely? ( I have a way for that)
Or to remotely override turn it off?

Are to trying to warm the house up or save gas?