Gas meter out of credit, boiler won't light Radiant RSF 24 E/SLIM

[graann]

Hi,
I had a prepayment gas meter fitted a couple of years ago and always kept it in credit.
I ran out the other day and since I have topped up the meter, I can not start the boiler.
Locks out.
I believe it is air trapped in the gas pipe as I have had a problem like this before, always when the credit runs out.
Can anybody give me any idea how long it will take the air to be purged out of a 15mm pipe approx 20 metres long by using the pilot to bleed the air ? ie normal starting sequence ( locking out after 15 secs , suggested reset time 3 minutes).Radiant RSF 24 E/SLIM

Not Gas Safe , employed as a maintenance electrician 38 years.

Thanks

 

[Mike Jackson]

It won't be air trapped in the pipe, how would it get in there? Make sure you have reset the gas meter correctly. It could be a problem with the gas valve or thermocouple.

 

[graann]

It won't be air trapped in the pipe, how would it get in there? Make sure you have reset the gas meter correctly. It could be a problem with the gas valve or thermocouple.

Hi,
Thanks for your reply, it is appreciated.
I wonder if you could explain why the boiler has run for the last two months until I run out of credit then thats when I have problems.
Happens every time I have run out of credit.

Thanks
Graham

 

[armourer]

Have a look at the gas meter and make sure as well as enough credit it says "ON" and not "OFF" in the corner.

As above it wont be air.

MI's and instructions to relight can be found here.
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[DLMURL]http://www.solvgroup.com/uploaded_files/File/RADIANT_BRUCIATORISliminstruction99943NA.pdf[/DLMURL]

 

[graann]

Many thanks for your help.
Yes , gas meter is on.

Thanks
Graham

 

[diamondgas]

Maybe it just likes being under pressure ? :rofl:

There's no reason once you re-establish the gas for the boiler deciding to take the hump! Unless that is it's 6 month down the line. I've known of installs needing purging then

 

[graann]

Hi,
Many thanks for your reply and thoughts.
This is the longest the boiler has refused to light after running out of credit.
What ever the problem is , always happens then.
Used a company in Bristol last time I had a diferent issue.
Will try them again if the situation continues
Once the boiler has lit once , there are no other problems.

Graham

 

[diamondgas]

Now this is a techy thought okay! ... If this is an HE boiler then it will suck the livin daylights out of the gas before shutting down. What's to say that when the zero compensating governor 'relaxes' atmospheric presure works in reverse and then enters back through the gas valve? I'd like to know if that were possible?

 

[Chrisgy]

I'd say it will be air. If it didn't lock out for a while and carried on with the gas valve open why wouldn't the gas pipe be full of air

 

[REDSAW]

proberbly because there is a gas escape else where before the boiler.
does your cooker light, or have you knocked the meter?.

get an engineer is the only legal way to sort it.

 

[graann]

Now this is a techy thought okay! ... If this is an HE boiler then it will suck the livin daylights out of the gas before shutting down. What's to say that when the zero compensating governor 'relaxes' atmospheric presure works in reverse and then enters back through the gas valve? I'd like to know if that were possible?

Now thats out of my league but I will , as a matter of interest find out a bit more about what you are saying.
I will call the experts for any actual work on the boiler but I am curious.
What is a HE boiler ?
Why will the boiler suddenly start acting normal again ?

One other thing if you don't mind.
When the gas meter shuts the valve on zero credit , does the boiler continue to run until all the gas has run out in the pipe to the boiler or will the boiler lockout as there is no gas pressure feeding it?
Will the gas pipe always have gas in it , so should start as soon as credit is applied, (after going through the boiler start sequence ? )

Thanks
Graham

 

[graann]

No cooker , boiler only appliance, meter not knocked, thanks for your reply.

Graham

 

[diamondgas]

Now thats out of my league but I will , as a matter of interest find out a bit more about what you are saying.
I will call the experts for any actual work on the boiler but I am curious.
What is a HE boiler ?
Why will the boiler suddenly start acting normal again ?

One other thing if you don't mind.
When the gas meter shuts the valve on zero credit , does the boiler continue to run until all the gas has run out in the pipe to the boiler or will the boiler lockout as there is no gas pressure feeding it?
Will the gas pipe always have gas in it , so should start as soon as credit is applied, (after going through the boiler start sequence ? )

Thanks
Graham

Gas meter shuts off but the boiler will try to "fire". Modern "HE" high efficiency boilers work slightly differently in that they "suck" gas through the boiler rather than religh on gas being 'pushed' through them. My thoughts were along the idea that the gas valve is designed to hace suction downstream to the burner. However if the meter shuts off there is the possibility of there being a 'negative' pressure pressent in the system gas supply if the meter has shut off! My thoughts are whether the gas regulator (gas valve) has been designed to accomodate negative pressure up stream of its conection?

Just curious TBH

 

[armourer]

My thoughts are if its a sealed gas pipe with no other appliances.
How can air get into the system?
I maybe agree with the negative pressure caused by the premix fan sucking but as soon as the gas is turned back on straight back to positive?

 

[diamondgas]

Agree once turned back on ... My thoughts are what happens within the gas valve once the fan on the boiler shuts down? If The gas suply will have to remain under negative pressure I'd assume until the gas at the meter is resumed. or the governor allows air to back flow through the valve to resume equal pressure? Who knows?

 

[REDSAW]

would going outside sniffing the flue for gas while relighting be worth a try?

 

[tamz]

Now this is a techy thought okay! ... If this is an HE boiler then it will suck the livin daylights out of the gas before shutting down. What's to say that when the zero compensating governor 'relaxes' atmospheric presure works in reverse and then enters back through the gas valve? I'd like to know if that were possible?

Good thinking Diamond and i don't know if it is possible, but, when the gas is re established it would do the same thing and kick back in.

 

[arran197]

It will probably be air. Be persistent. I go to a boiler. On the third floor sometimes, the pilot won't relight and I have to purge it, but that's not something you can do, so continue to hold down the pilot button and try the spark every couple of minutes. Just get yourself a normal meter, not only are they much cheaper, this won't ever happen unless there's a problem with the boiler.

 

[kay-jay]

heres one for ya

how much credit did ya put in? had some issues with a prepay meter myself in my old flat. what happens is if you use up your 'emergency credit' simply topping up by that value will not re-establish gas supply. what you need to do is top up by the 'emergency credit' value plus a tenner. don't know how your particular meter/gas supplier works but thats what i had to do.....

 

[bobby5156]

Aaran 197, Is a prepay meter more expensive, I thought the electric/gas companies advertise this as a cheaper option? Seems silly if someone who struggles to pay bills would be better off on prepay if the supply rates are more expensive.

Bobby

 

[REDSAW]

like about 25% more expensive as they charge more for the privelage?

 

[MattWeth]

Aaran 197, Is a prepay meter more expensive, I thought the electric/gas companies advertise this as a cheaper option? Seems silly if someone who struggles to pay bills would be better off on prepay if the supply rates are more expensive.

Bobby

Card meters are always more expensive.
Landlords like them because they don't get any hassle with the utility company over non-paying tenants who do a flit and the utilities like them because they get more money per unit, don't have to read the meter and don't have to enter into a credit agreement with the home-owner.

For some home-owners or tenants with a poor credit rating, a card meter is the only way they can get gas. As you say, this is often a double whammy as they are probably struggling financially anyway and have to pay more...

 

[graann]

Hi,
Many thanks to everybody who replied and offered advice.
I went through the starting sequence countless times over a few days.
Yesterday evening , having not tried it for over a day , tried the starting sequence and the flame was established immediatelely.
I know from my experience with this boiler , as long as the meter is in credit , I won't be having this problem again.
It will be staying in credit !


Thanks
Graham


i

 

[PlumbBobBob]

good to know you are sorted finally

 

[stevetheplumber]

i would be more worried about the grossly under sized supply pipe to this boiler 20m of 15mm pipe ??????