viessmann 100 weather comb

[Gasmk1]

went to service a viessmann 100 and install weather comp fitted the lead to x21 as per wired the sensor but the boiler was not seeing the sensor, phoned viessmann and went through it, sensor is correct one 5K the resistance was ok, checked all connections and the were fine anyone else had this problem is it the sensor or new or connection cable (both brand new) or is it the board. viessmann technicaal couldnt help

 

[townfanjon]

Weird one this , defo no breaks in the wire from sensor to board . Test each individually .

 

[Gasmk1]

yes pretty sure all wires ok was getting resistance at all connections,
will do cont check on cable tomorrow

 

[ShaunCorbs]

Did you prog the boiler to say I want to weather comp ?

Have had one where it wanted a restart/ set

 

[Gasmk1]

its the old one with 2 dials not the touch screen.

 

[ShaunCorbs]

its the old one with 2 dials not the touch screen.

Fair enough think it still needs a reset

 

[Gasmk1]

how do you do a reset the viessmann tech didnt advise it

 

[townfanjon]

Heating dial turn clockwise , but hold it there for a few secs otherwise serv mode comes on .

 

[ShaunCorbs]

Think you have to turn both knobs to something best ask tech as I can't remember now

 

[townfanjon]

You would think connecting it up to x21 it would recognise it straight away , what type / size of wire are you using ?

 

[Gasmk1]

it should recognise straight away tried first with wire i was using thought it may be that so just connected up with short length of wire about 6 inches same outcome

 

[townfanjon]

it should recognise straight away tried first with wire i was using thought it may be that so just connected up with short length of wire about 6 inches same outcome

It’s exactly what I would have done , does sound like board now , bloody expensive to try , are you using bell wire ?

 

[townfanjon]

It’s exactly what I would have done , does sound like board now , bloody expensive to try , are you using bell wire ?

Have you connected to 3 & 4 on x21 ?

 

[Gasmk1]

Yes 3 and 4 have done several before on the 100. at my last house I installed it on the 200 never a problem till this one. Boiler is about 5 or 6 years old I am leaning more towards the board being faulty

 

[townfanjon]

Long shot , still under warranty ?

 

[Gasmk1]

no these only came with 5 year customer never had it serviced before now, no books all lost or misplaced when house renovated

 

[townfanjon]

no these only came with 5 year customer never had it serviced before now, no books all lost or misplaced when house renovated

Pffttt, if its board try fixed repair it maybe cheaper

 

[Gasmk1]

will just let customer know how much but it takes the savings out of the equation. take a lonhg time to recoup the costs. unless anyone has a freebie board they have removed )