Siemens RDJ10RF Theromstat and inconsistent heating

[Tomgeek]

I’m really hoping someone can help me, I’ve just moved into my first house and am absolutely stumped by the boiler and thermostat.
we had a plumber come out for a service and he said everything was fine, but did mention that (in his opinion) the thermostat was ‘one of the worst’. We didn’t think to ask how to work the whole system as the first day we moved in and turned the boiler on, the radiators came on.
The problem is that we can’t get them back on, at least at a time we want. The thermostat is a Siemens RDJ10RF, and while all of the instructions indicate it has a receiver, unless it’s wired directly inside the boiler we literally cannot find it and we’re not exactly in a large house (two up two down)
Beneath the boiler is a ChannelPlus H17XL, which I’m not sure if controls just the water or also the heating? Setting the Siemens thermostat does nothing, and occasionally when the ChannelPlus is turned on, the radiators will come on around midday for maybe an hour then go off.
Am I missing something obvious/is there something in particular I should be doing? I don’t know where to start with the mismatched Siemens thermostat and whatever the ChannelPlus is?

 

[flameport]

The H17XL is a timer, and will turn the heating on at whatever times are set. If that's the only thing controlling the heating, pressing the Boost button once should turn the boiler on immediately and the radiators should get hot within a few minutes.

The Siemens RDJ10RF is a programmable thermostat, and does not need any other timer or controls - if fitted it would be the only thing, as it has both time and temperature in the same unit.
It's radio control, and the other part of it is one of these:

wired to the boiler. Pressing the Override button should activate the boiler immediately.

For hot water - what make and model of boiler have you got?

 

[terryplumb]

The Siemens stat needs a receiver ,should be near the boiler.
The Chanel plus is simply a single Chanel timer / programmer.
What boiler do you have ?
Some pics of around boiler ,and hot water cylinder ( assuming you have one) would be helpful.

 

[Deleted member 267285]

Are you sure it’s the RF model and not hard wired? Is it on the wall? As per flameport, what boiler do you have?

 

[Tomgeek]

The H17XL is a timer, and will turn the heating on at whatever times are set. If that's the only thing controlling the heating, pressing the Boost button once should turn the boiler on immediately and the radiators should get hot within a few minutes.

The Siemens RDJ10RF is a programmable thermostat, and does not need any other timer or controls - if fitted it would be the only thing, as it has both time and temperature in the same unit.
It's radio control, and the other part of it is one of these:
View attachment 246159
wired to the boiler. Pressing the Override button should activate the boiler immediately.

For hot water - what make and model of boiler have you got?

Thank you for your reply! It’s the the other part of it we can’t find, we have all the instructions saying it should be wired into the boiler, but unless it’s somehow inside the boiler it’s not something we can find at all and there are no obvious wires coming off and leading anywhere.
The boiler is a Worcester and I’m not sure if it’s relevant but we’re on LPG gas as the village has no gas mains. We do have full bottles and water is being heated on demand.

EDIT: inside boiler has a more specific label - Greenstar 24i junior combi MK IV if that’s helpful!

 

[Tomgeek]

Boiler picture:

A2949C2A-DB48-4755-9520-DE6CFBB3681A

• Tomgeek
• 6 Oct 2021

There’s nothing behind the microwave other than the on/off switch for the boiler. The Thermostat is definitely an RDJ10RF, it’s free standing and we have the original packaging and instructions indicating that it did come with a receiver

 

[terryplumb]

Lower the flap on the timer and show us a close up ,in focus pic,of the display. It appears that the stat isn't doing anything ,just stuck on the wall somewhere....odd.

 

[Tomgeek]

2E2EB2F1-B047-488D-A80E-13E381184F25

• Tomgeek
• 6 Oct 2021

There’s only a couple of setting options - On, off, auto on and all day, the last two of which you can set times for

EDIT: advance and boost don’t seem do anything. Boiler only kicks in when hot tap is turned on. And twice it’s come on at midday for an hour ish for radiators

 

[Tomgeek]

In a fit of cold and numb fury my husband has removed the front of the boiler:

C11B4511-A520-42F5-947B-84BE3BFC2FE0

• Tomgeek
• 6 Oct 2021

and we’ve found the receiver shoved inside ‍ Now attempting to reset it

 

[terryplumb]

 

[Tomgeek]

Can’t get them to talk to each other but at least we’ve found the other bit I guess?
We can’t get it out of the boiler without rewiring it….I’m guessing it probably shouldn’t be stored there?

 

[terryplumb]

You shouldn't really have removed the boiler casing. I have never seen a receiver placed within the boiler like that ,and to be frank can't see why would want to.

 

[Tomgeek]

We followed the instructions to remove the front and haven’t touched anything else in there, I can’t see how else we could have gotten anywhere

 

[terryplumb]

Well ,you are where you are. Have you got your boiler working ?

 

[Tomgeek]

Nope! Reset the two Siemens devices and paired them up but the boilers not responding to the thermostat settings. However I’m no longer baffled by the setup as a whole and will try more trouble shooting tomorrow