IDEAL MEXICO CF 65 AFTERBURNING problem

[Geyser]

I am trying to diagnose a problem for a friend on an IDEAL CF65. The symptoms are the boiler engages heats up and flow and return is a-OK. As the temp increases after a period of hours the and the system is turned off, water and steam is heard overflowing through the vent pipe, into the F&E. This continues intermittently throughout the day. On observing the burners the flames are still flickering (not vigorously as when the system is on) despite the system actually being off. We believe that the problem is a gas valve issue and have been quoted £60 for a new one. Although I am a qualified Plumber I am not CORGI registered so I cannot fit the valve! However, I would appreciate some guidance, as to other possiblities in case our diagnosis is wrong.
Many thanks to you all for any help. Leo.

 

[ollski]

bear with me there is a manufacturer recall on some mexicos but cant remember why off the top of my head....will find out for later though unless anyone else can enlighten us

 

[ChrisR]

If the flames are on when its supposed to be off then I reckon that makes it "immediately dangerous" and would disconnect the gas, and fix warning notices. If the owner objects you call the police and transco. £60 sounds very reasonable for a gas valve.

 

[kevplumb]

could be shulphidation not allowing valve to close had a run of it a while back

 

[Geyser]

could be shulphidation not allowing valve to close had a run of it a while back

Thanks Kev...as per your suggestion we'll remove it and check for sulphidation.
PS - This is a great site. Thanks to you all.

 

[namsag]

Geyser new gas valve required as the ones fitted on the mexico are basically a sealed unit and you won`t get into the workings to clean anything . Mind you find it funny you feel confident enough to strip it out and clean it but not change whole unit , which is less of a job

 

[Geyser]

Thanks Namsag, didn't realise it was a sealed unit. I've only "assisted" in fitting one boiler and that was a Potterton Suprima 50. It never worked first time either as the electrode had detached itself during transit and I had to call out an "elder" to help me. His advice was: "remove the cover!" And lo and behold the problem was evident straight way. Taught me to inspect first before doing anything!

 

[ollski]

This is as much detail as I can find at the moment:

http://www.tradingstandards.gov.uk/cgi-bin/shropshire/newsitem.cgi?file=*safe0467.txt

 

[croydoncorgi]

If your boiler is really a CF65, this recall does not apply. It's only for boilers installed after December 2001.

OTOH, if the gas valve is sticking open it's 'immediately dangerous' and the valve needs to be replaced before the boiler is used AT ALL.

You've already had this advice from someone else and not reacted.

 

[Geyser]

If your boiler is really a CF65, this recall does not apply. It's only for boilers installed after December 2001.

OTOH, if the gas valve is sticking open it's 'immediately dangerous' and the valve needs to be replaced before the boiler is used AT ALL.

You've already had this advice from someone else and not reacted.

Sorry, am I supposed to react on advice immediately even if in my opinion the system is not dangerous or hazardous. If it was either of these we would know and we would shut it down. Though clearly the situation it is far from IDEAL!!
Correction: It's not immediately dangerous if it is an intermittent fault and that is what we've got. When needed the vent pipe to the F&E is doing it's job, aka a safety valve. We will replace the gas valve, we are just awaiting some technical doc about the boiler from IDEAL. The boiler works fine there is no gas escaping and boiler thermostat (aka another safety device) works a-OK.

 

[PEDANTICVINDICTIVEMAN]

Methinks someone is going to do it themselves unregistered or not.

 

[kevplumb]

if the valve is passing gas when it should be off its ID no question of what you think

 

[ollski]

If your boiler is really a CF65, this recall does not apply. It's only for boilers installed after December 2001.

OTOH, if the gas valve is sticking open it's 'immediately dangerous' and the valve needs to be replaced before the boiler is used AT ALL.

You've already had this advice from someone else and not reacted.

Sorry, am I supposed to react on advice immediately even if in my opinion the system is not dangerous or hazardous. If it was either of these we would know and we would shut it down. Though clearly the situation it is far from IDEAL!!
Correction: It's not immediately dangerous if it is an intermittent fault and that is what we've got.

Sorry, your opinion it neither correct nor valid as you do not have the technical knowledge to make a judgement...it IS ID.

 

[Geyser]

if the valve is passing gas when it should be off its ID no question of what you think

Let me get this right. You diagnose my problem for me but because it isn't actually passing gas unignited you still think it's dangerous. I disagree, it's a fault and it needs to be fixed but it isn't immediately dangerous.
And where do you get off, telling me I have no opinion. I may not be CORGI reg'd but I trained at college for 3 years, so I do understand gas and worked closely with it, BTUs, KWs, burner pressures all the maths it entails, theory and practice.
NB: You're final sentence doesn't show me that you are exactly the voice of reason.

 

[Geyser]

If your boiler is really a CF65, this recall does not apply. It's only for boilers installed after December 2001.

OTOH, if the gas valve is sticking open it's 'immediately dangerous' and the valve needs to be replaced before the boiler is used AT ALL.

You've already had this advice from someone else and not reacted.

Sorry, am I supposed to react on advice immediately even if in my opinion the system is not dangerous or hazardous. If it was either of these we would know and we would shut it down. Though clearly the situation it is far from IDEAL!!
Correction: It's not immediately dangerous if it is an intermittent fault and that is what we've got.

Sorry, your opinion it neither correct nor valid as you do not have the technical knowledge to make a judgement...it IS ID.

Don't be sorry. My opinion may not be 100% correct but neither may yours. I gave you the symptoms of the problem and we are confident what the reason is. You are quite incorrect about my technical knowledge and it just smacks of arrogance on your part. If you had cared to ask I would have told you I trained at college for 3 years and worked with gas for a large part of the syllabus. Doesn't this entitle me to an opinion? Obviously not in your eyes. Now let me get this right: is this a forum or a club with a "few" eliteists, with rather large egos?