Boiler seems to have 2 controllers !?

[Kwikphix328]

Hi,

Have just bought a new (to us !) Bungalow. We have had the house completely rewired. We are not living in it at the mo due to other works required and I am working away.

However the GCH is permanently on at max temp, I found it strange that there are 2 different Controllers wired in.

The Boiler : Baxi DUO-TEC COMBI 24 HE A
Controller 1: Drayton LP111Si (hardwired)
Controller 2: Siemens RCR10/433 & RDJ10RF wireless set.

The GCH was working satis prior to the re-wire, during the viewing the previous owner demonstrated the Seimens Controller as the in use thermostat, so suspect that the Electricians have made a mistake.
I Suspect that I only really need the Siemens 'or' the the Drayton Controllers connected, and as the seimens has a remote wireless Thermostat this would be the preferred option.


The Electrician is coming back for another look and he did say that the boiler wiring was 'a mess'.

I think that the previous owner of the house was a keen, but not particularly skilled DIY'er..

Can anybody advise further ? Please.

 

[stem]

Drayton LP111Si is a simple, single channel timeswitch so usually simply turns the heating on/off according to pre-set times.

Siemens RCR10/433 is a programmable room thermostat that is capable of controlling both the heating time and temperature settings in the one unit.

Siemens RDJ10RF is also a programmable room thermostat.

Sometimes programmable thermostats are installed to replace a standard room thermostat that had only provided temperature control. When this happens the LP11Si becomes redundant so is normally set to be permanently on 24/7 and the programmable thermostat takes total control.

But why are there two thermostats? You suspect that only one is actually in use, and that maybe the case although usually if a new thermostat is installed it simply replaces the existing one which is discarded.

Is it possible that there are different heating zones, is one programmable thermostat controlling the living areas and the other the sleeping areas? This is a common arrangement and is a requirement of the building regulations for new builds.

Is one for an extension that was added to the property later? A conservatory? Usually where they are located can give a clue.

It all depends upon what the devices are wired up to and actually controlling; and there could be many different possibilities there, so would be anybody's guess really.......I would start by identifying what each of the controllers is actually doing by setting them all to be 'off' and turning them 'on' individually one at a time to see what happens. If nothing works when you do that, then, try switching the Drayton LP111S 'on' first and then the thermostats individually.

Or you could simply ask the previous owner of the property what they do.

 

[CBW]

It might be they have upgraded the thermostat, but you have a time clock and programmable wireless thermostat.

Edit: @stem - just seen your reply, I think the rcr10 is a receiver for the rdj10

 

[stem]

Edit: @stem - just seen your reply, I think the rcr10 is a receiver for the rdj10

Quite correct. my misunderstanding. Because the thread title mentioned two controllers, when @Kwikphix328 said:

Siemens RCR10/433 & RDJ10RF wireless set.

I took that as being two 'sets' of thermostat and receiver.

Having read it again I think you are right and the two controllers are the timeswitch and thermostat, the numbers 1 & 2 used should have given me a clue

If so, it means:

Controller 1 = Drayton LP111Si a simple, single channel timeswitch to turn the heating on/off according to pre-set times.

and

Controller 2 = RDJ10RF thermostat linked to a RCR10/433 receiver

Then it looks like a fairly common situation where a programmable thermostat has replaced replace a standard room thermostat that had only provided temperature control. And, if the LP11Si hasn't been decommissioned is now redundant and would be set to be permanently 'on'.

OP try just switching the heating 'on' with the room thermostat and seeing if it works with the Drayton LP111Si off. If it does just use the Siemens room thermostat for control. If it doesn't come on then, try setting the Drayton LP111Si to be permanently 'on' and seeing if you can use just use the Siemens room thermostat for control.

 

[Kwikphix328]

Thank you for the speedy replies !

When I went into the house to check the Electricians work the house was like a Sauna, Siemens remote thermostat showing 27 deg ! £££ rising into the attic and through the (leaky) roof.

I adjusted the Siemens remote down to a low setting, 15 deg, which should have turned off the radiators however they were still producing max heat over the next 3 -4 hours that i had time to stay at the property.

As the outside temp was 2 deg and still snow on the ground ( Newcastle area last week), i just left it for the next week.

I tried to adjust /control the temp via the Siemens wireless combo, however even though the two Siemens units see each other tirelessly, I don't think the siemenscis controlling the temp, I think that the Drayton is the master control over the boiler.

I will download the installation and operation manuals for the boiler, Drayton and Siemens Controllers, also search for another room thermostat that the Drayton may be connected to ??

Your replies have given me a few ideas to research further and pointed me in a direction that I suspected.

 

[stem]

I think that the Drayton is the master control over the boiler.

Sounds plausible, if the thermostat doesn't seem to be controlling anything and it is just the Drayton. The Drayton LP111Si is only a timeswitch so there won't be any thermostatic control which might explain why it just keeps getting hotter and hotter when it is on.

 

[old duffer]

typical senario of yet another example of an NVQ "engineer" being allowed to make decisions without the ability to investigate.