Unexpected boiler shut-down after yearly service

[Lucky Luke]

Hi, experts. On Saturday the 5th Oct (2019), an engineer employed by Vaillant (i.e. an official Vaillant engineer) came and serviced our Vaillant EcoTEC Plus 824 boiler. He left, saying everything was OK, and signed the required document.

Early today (Tuesday the 8th Oct., with only two days separating today and the day of the service), I found that neither the heating nor the DHW were working. When I looked, the display said: Safety shutdown — water shortage. The water-pressure reading was very low (I think it was .4).

Being very inept with matters of this kind, the only thing that I could do was to open the valves, and inject more water into the system (the pressure level is now halfway between the top limit and the bottom limit in the icon shown on the display). When I pressed the reset button, if fired up as normal. It has remained OK up until 2.00 pm (touch wood).

However, when I rang Vaillant about this, in case something was wrong and that it may fail again, they gave me short shrift. The woman said, "Your boiler is working, so we cannot discuss this matter any further" (or words to that effect).

This failure bothers me greatly, because the boiler has worked perfectly for the last two years, since having a new gas valve fitted by Vaillant. I would have thought that, so soon after a service, there would be nothing whatever that could cause such a failure. Yet, something did!

Can anyone on this forum enlighten me as to any possible things could have caused the boiler to fail? And is this likely to happen again, out of the blue?
With hopeful thanks in anticipation,
A.W.

 

[ianmcd]

sounds like during the service the boiler was drained to check the expansion vessel and when refilled therehas been some trapped air, nothing to worry about unless it keeps doing it just keep an eye on the presssure guage

 

[Lucky Luke]

sounds like during the service the boiler was drained to check the expansion vessel and when refilled therehas been some trapped air, nothing to worry about unless it keeps doing it just keep an eye on the presssure guage

Thanks for that, Ian. I shall keep checking the pressure, as you advise. However, if it was trapped air, can it be released from the top radiator, or would there be some other procedure?

 

[ianmcd]

The boiler has an automatic air vent, sounds like it has been released there hence the need top the pressure up

 

[ScottishGasMan]

as above very possibly theres been some air vented off the boiler after the service, unusual but very possible. The pressure goes down when there is a loss of air or water from the system. Keep an eye on it and top up as you ahve done as neccissary if required until you have a soloution for it.

(the other possibility that happens more commonly, is that the pressure has be low to begin with, the sensor for the pressure in the boiler may have been replaced due to dirt causing it to stick, and now there is a new one in there its detecting a pressure loss from the system and shutting the boiler off appropriately)

 

[durhamplumber]

Hi, experts. On Saturday the 5th Oct (2019), an engineer employed by Vaillant (i.e. an official Vaillant engineer) came and serviced our Vaillant EcoTEC Plus 824 boiler. He left, saying everything was OK, and signed the required document.

Early today (Tuesday the 8th Oct., with only two days separating today and the day of the service), I found that neither the heating nor the DHW were working. When I looked, the display said: Safety shutdown — water shortage. The water-pressure reading was very low (I think it was .4).

Being very inept with matters of this kind, the only thing that I could do was to open the valves, and inject more water into the system (the pressure level is now halfway between the top limit and the bottom limit in the icon shown on the display). When I pressed the reset button, if fired up as normal. It has remained OK up until 2.00 pm (touch wood).

However, when I rang Vaillant about this, in case something was wrong and that it may fail again, they gave me short shrift. The woman said, "Your boiler is working, so we cannot discuss this matter any further" (or words to that effect).

This failure bothers me greatly, because the boiler has worked perfectly for the last two years, since having a new gas valve fitted by Vaillant. I would have thought that, so soon after a service, there would be nothing whatever that could cause such a failure. Yet, something did!

Can anyone on this forum enlighten me as to any possible things could have caused the boiler to fail? And is this likely to happen again, out of the blue?
With hopeful thanks in anticipation,
A.W.

Maybe you should become "" never worried"" and stress less!

 

[Lucky Luke]

as above very possibly theres been some air vented off the boiler after the service, unusual but very possible. The pressure goes down when there is a loss of air or water from the system. Keep an eye on it and top up as you ahve done as neccissary if required until you have a soloution for it.

(the other possibility that happens more commonly, is that the pressure has be low to begin with, the sensor for the pressure in the boiler may have been replaced due to dirt causing it to stick, and now there is a new one in there its detecting a pressure loss from the system and shutting the boiler off appropriately)

Well, before the engineer came to do the service, the pressure was not low at all (I kept a regular check on it). Whether he altered it is not known to me. I trusted him to do everything correctly, of course. For the boiler to "fail" for whatever reason, after an official service, came as quite a shock. Thanks for your comments.
A.W.

 

[Lucky Luke]

The boiler has an automatic air vent, sounds like it has been released there hence the need top the pressure up

Who am I to know what happened, Ian? If that's what you think is likely, I accept it. My main concern (and relief) is to hear whether there could be anything wrong with the boiler, immediately after a service. Today, (Wednesday noon), the pressure seems to have fallen just a bit since it was topped up. I shall keep an eye on it every day for the next week.

 

[ianmcd]

The boiler pressure guage always alters slightly depending if the boiler is hot or if the pump is running, that is perfectly normal, as said just keep an eye on it

 

[Lucky Luke]

The boiler pressure guage always alters slightly depending if the boiler is hot or if the pump is running, that is perfectly normal, as said just keep an eye on it

Read more: https://www.diynot.com/diy/threads/...wn-after-yearly-service.530891/#ixzz61s1LhO5Q

OK mate. Will do!

 

[Lucky Luke]

The boiler pressure guage always alters slightly depending if the boiler is hot or if the pump is running, that is perfectly normal, as said just keep an eye on it

Ian (and the other helpful people that commented), just so that you will know the real and final outcome of this matter, I did check the pressure on Thursday last (10/10/19), and it had gone down. However, I did not top it up, but waited. On Friday morning, the boiler had shut down again. I asked Vaillant to come out, and an engineer came this (Sat.) morning (12/10/19). He found the fault immediately. It was the expansion vessel, which had a pinprick hole in it (hence the two and a half days for it to reduce pressure). I cannot see how the first service engineer could have missed that. In fact, he remarked that there HAD BEEN a "small leak". I said that I did not know, and that it had worked perfectly for the last year (when a new gas valve was fitted). I said, "But there is no leak now, is there?" His reply was that there was no present leak!! Hmm!

I was right to be worried!
A.W.

 

[Mottie]

Phew! At least you keep your forum name.

 

[ianmcd]

there is a common saying in the industry the Industry,rhymes with myfeckinarse

 

[Wigum]

To be fair, the guy could of recharged the vessel and the core could of started passing.
Things like this happen and maybe im picking you up wrong but you seem to want to find someone to blame.
Calm down. Far more important things to worry about