Vaillant Sine 18 - not quite right.

[The831Bunny]

Thankyou Mike, a diminishing need for the ‘knowledge’ now as they’ve nearly all gone. Glad it helped somebody in their hour of need. When I joined Vaillant and during my engineer training in Germany, I watched these boilers roll off the production line in their final manufacturing year. It was 1988. Who knew they would still be going strong at least 31 years later? All the best.

 

[Gasguru]

Have a look at the expansion vessel...the green label will have the manufacturing date of the vessel to give an idea of boiler age. Most of my customers Sines lasted 25 years..all built around '82...plenty of Ecotecs ripped out at 5 years...but the myth of German quality persists.

 

[Mike1501]

Thanks Gasguru.
Yes I found the label and the manufacturing date is 1982.
That means it must be the original boiler as this house was built in 1983/4.
So the boiler is 37 years old and has been in use for 35 years.
Sure, various bits have been replaced over the years but that is not bad going
for a gas boiler is it. Maybe the fact it runs on LPG makes a difference?
Now that it is running so well (thanks to The831Bunny), I am tempted to see if it will last to 40 years, rather than replace it this summer, which was my original intention.

Mike

 

[Gasguru]

If I were you I'd get a CO alarm fitted....some of my customers boilers finally died due to the top vitreous hood splitting in the corners.

 

[basherbill]

i am well aware that this thread is two years old but i would just like to add that my vaillant combi was installed in june 1985, and its still going!!

 

[DP]

I still look after one of these boilers and have some spares including the heat exchangers

 

[Wantinghelp]

Hello The 831Bunny I live in Dunster and am desperately looking for an experienced engineer familiar with the sine 18T3W Contact me at the Yarn Market Hotel Dunster if you know of anyone. You can find us on the web

 

[ianmcd]

Do you own the hotel ? some would come free if you put them up and free beer for an evening , great old boilers but sadly not many left who know their way around them

 

[Wantinghelp]

Hello Ian

Yes, I own the hotel. The sine 18t3w serves the staff accommodation and will be needed from the end of September when the nights get colder

Your suggestion sounds a good idea. I am on holiday for the next couple of weeks but anytime after that that suits you SUBJECT TO an available double or twin room in the hotel .

I am not sure if one can put contact details on this site but these can be found on the yarnmarkethotel website and I will look out for your message

 

[DP]

Hello The 831Bunny I live in Dunster and am desperately looking for an experienced engineer familiar with the sine 18T3W Contact me at the Yarn Market Hotel Dunster if you know of anyone. You can find us on the web

What is the matter with your boiler

 

[Wantinghelp]

The boiler overheats and then the high temp safety device cuts in

 

[DP]

The boiler overheats and then the high temp safety device cuts in

Take it it is doing that during hot water operation.
Put the preheat off and see if boiler still doing that.
Does it do that all the time or randomly.
With hot tap running, what temperature is the temperature gauge showing
Reduce the thermostat setting and see if that makes a difference
Look at the flame when hot tap is running, ( get some one to gradually reduce the flow rate). Flame should reduce in height. As the hot water flow rate is increased, burner will go to full rate.

The temperature gauge, with hot tap at max flow, should indicate around 70 degrees. The O/H stat chops the drive at 95 degree or so

If the flame size does not adjust to load ( heating of cold water), then of course O/H stat will kick in.

Checking temperature of primary water in and out of the main heat exchanger would assist in fault location. Data logger could also help narrow the issue.

Final drive for burner modulation unless I am mistaken is 2N3055 power transistor.

You need someone who has worked on this boiler and understands why makes it tick.

 

[Wantinghelp]

Thanks DP for this guidance. I am on holiday this week but will investigate when I get home
Antony

 

[Dew_Zee]

Thankyou Mike, a diminishing need for the ‘knowledge’ now as they’ve nearly all gone. Glad it helped somebody in their hour of need. When I joined Vaillant and during my engineer training in Germany, I watched these boilers roll off the production line in their final manufacturing year. It was 1988. Who knew they would still be going strong at least 31 years later? All the best

 

[Dew_Zee]

Hello all. Anyone out there with the expertise to repair my 1987 Sine? I’m in Huddersfield, West Yorks. Thanks.