Installing a NEST to a Vaillant Turbomax

[Vim]

forgot to attach

 

[Thanos]

Ok thanks for the pic. I can see your heatlink is the recommended 30cm away from the boiler. I'll try and find out more info about why it has to be 30cm away from the boiler.

 

[bernardgreen]

I'll try and find out more info about why it has to be 30cm away from the boiler.

The speed controller for the boiler's fan creates and radiates a small amount of spurious radio frequency energy. If the receiver of a wireless system is placed too close to the boiler then the radio frequency energy from the boiler can degrade reception of commands to the boiler.

 

[DP]

Some of the bullpoop being posted here is beyond belief

 

[Thanos]

Thanks for that info bernardgreen I think I've found a way round this. I will run a longer 4 core cable from the boiler to the heat link receiver and put the heat link on top of the cupboard next to the boiler which will give me more than 30cm distance from the boiler.

 

[bernardgreen]

Some of the bullpoop being posted here is beyond belief

Perhaps if plumbers diagnosing problem installations had a open mind then they might be more sucessful at fault finding.

Gas boilers
UKQRM members have reported interference issues from some Vaillant boilers. Their control electronics produce interference from 7MHz to 21MHz with a peak centred around 13MHz. Radio Amateur, Andy Summers G4KNO,

offers this method which he used to cure his Vaillant boiler interference.

offers this method = http://g4kno.com/emc/boiler_noise/boiler_noise.html

 

[Thanos]

Hi everyone just giving you all an update I followed mikeyd instructions and installed my nest successfully. I put the heat link 20cm away from the boiler and everything is working ok. Thanks for everyone's help.

 

[Dan Robinson]

Nowt like RTFM.

 

[Dan Robinson]

And before Berny gets on his high horse again about wireless controls - we've been fitting capacitors and whatnot to hard wired controls for years to get rid of interference, both of the induced voltage and RF varieties.... A Mexico being the last I remember working with that needed one replacing - not a wireless thermostat in sight.

 

[Thanos]

So Dan are you saying I should try to move the heat link or leave it where it is.
Thanks

 

[Dan Robinson]

I'm saying that they have put 30cm in there for a reason. With Honeywell controls, it is bizarre how critical that minimum distance is.

You may get away with it, you may start getting problems further down the line. Tricky to say.

 

[Steelmasons]

I must be doing it wrong all these years as I've fitted many BDR receivers within the case of a Worcester high flow 440/550...
Thanks for the tip , I guess I'll have to remove all these BDR's and install them 300mm away from the appliance...

 

[Dan Robinson]

I must be doing it wrong all these years as I've fitted many BDR receivers within the case of a Worcester high flow 440/550...
Thanks for the tip , I guess I'll have to remove all these BDR's and install them 300mm away from the appliance...

With the old CM's, for some reason, they were a lot more tolerant - my old house has a pair of them installed between a washing machine and Atmos Multi case, with the upstairs lighting and ring main cables almost touching. Not been a problem in 12 years; and I still service the system each year - seems the two CM67NG's have started to slip[ out of calibration though as the current owner says the temperatures are as little "vague"

Evohome etc are much more sensitive; I suspect because there is more data being transmitted and there is less tolerance to errors due to transmission time limitations. Could be wrong though - sure it is publishes somewhere in the RAMSES spec, although we are on RAMSES II now, possibly III.

R6660D I think was RAMSES I.

 

[Thanos]

Here is a picture of where the heat link is from my boiler. It is 20cm away from the top of the boiler.

 

[bernardgreen]

And before Berny gets on his high horse again about wireless controls -

When a modulated fan in the boiler is running the motor speed control and power creates a bit of spurious radio frequency energy. Not much gets out of the boiler casing but if the signal from the remote thermostat is weak then the signal to turn OFF may be corrupted or not received due to this RF interference. The ON command is received as the boiler is not running and hence no RF intereference from the fan motor. Some service technicians consider that as the ON command was received then the wireless link is working properly.

Some protocols require that the thermostat sends the ON command once then followed by repeated KEEP ON commands spaced a few minutes apart while the boiler should be burning. If the boiler does not receive the KEEP ON commands then it times out and switches OFF. Repeated ON commands instead of KEEP ON can result in the boiler stopping on time out and then re-starting when it receives the next ON command ( when there is no longer any spurious radio frequency energy from the stationary fan motor ). This can appear to suggest the boiler is cycling ON OFF due to a fault in the boiler and again the wireless link may not considered as suspect.

I di not know which if any domestic boilers have this fail safe protocol.

we've been fitting capacitors and whatnot to hard wired controls for years to get rid of interference, both of the induced voltage and RF varieties.

How do you "get rid" of RF interference in the pass band of the receiver ?