Why wont my pilot stay lit Glowworm Hideaway 100

[spartacus]

I have a 40 year old Glowworm Hideaway 100.

I have lived in this house for 8 years and it has been faultless, until recently. The pilot light won't stay on.

The boiler has been worked on by a Gas Engineer, but he is stumped and telling me I need a new boiler. I can not afford a new boiler, and and not convinced it is finished yet.

This is what happens...Turn the gas valve to pilot. Press the ignitor. The pilot ignites. Turn the gas valve to main burner, and the pilot goes out. It does not matter how long you hold down the gas valve on the pilot setting; it will stay lit until switched to main burner.

The gas engineer, has replaced the thermocouple, which was found to be snapped. He has also replaced the gas valve, as a bit of a "hail mary". He sourced the valve, but it made no difference.
The Flue Safety Device was also found to have a hole in it. I source a genuine glowworm thermocouple and safety valve.

There is no change. The pilot lights fine but will not stay lit.

Has anyone with experience got any ideas what might cause a pilot to refuse to go to stay lit?

Thanks

 

[Gasmk1]

As it’s a 100 it will have an overheat stat that the thermocouple is fitted through. These can be problematic. But if your present gas engineer can’t sort it try to get someone else

 

[spartacus]

As it’s a 100 it will have an overheat stat that the thermocouple is fitted through. These can be problematic. But if your present gas engineer can’t sort it try to get someone else

The overheat stat. I assume you mean the safety device. That has been replaced. I have checked continuity from the thermocouple to the gas valve. All good.

The flame is NOT pure blue though. I'm not happy about that.

I've asked him to disconnect the gas and check the pipes for blockage. Other than that I'm lost.

Where can you test for current from the thermocouple?

 

[Deleted member 120897]

You mentioned the flue safety device, this is separate from the overheat stat. Thermocouple is tested on the plug end and copper sheath. Agree with @Gasmk1, I think a different engineer may be needed.

 

[spartacus]

You mentioned the flue safety device, this is separate from the overheat stat. Thermocouple is tested on the plug end and copper sheath. Agree with @Gasmk1, I think a different engineer may be needed.

Cheers. We did have that out. I never considered replacing it. Found a really helpful video that helped me understand some of this stuff. ()

I will give the gas engineer one more shot at troubleshooting the problem before i look to get someone else on the job.

 

[Last Plumber]

I wouldn't bother. That is an easy fix for someone who knows the boiler and it sounds like you've bought parts unnecessarily already.
Get someone more experienced with those boilers. Aim at someone over 50 if you can. No ageism intended.

 

[spartacus]

I wouldn't bother. That is an easy fix for someone who knows the boiler and it sounds like you've bought parts unnecessarily already.
Get someone more experienced with those boilers. Aim at someone over 50 if you can. No ageism intended.

I would....but this guy is a "friend". Its kind of an insult to say...im going to get someone else. but yes. i might be reaching that point. His answer.....boiler is F@cked; get a new one. i dont agree. Maybe I'll find someone. Anyone here in Wirral?

 

[Last Plumber]

I would....but this guy is a "friend". Its kind of an insult to say...im going to get someone else. but yes. i might be reaching that point. His answer.....boiler is F@cked; get a new one. i dont agree. Maybe I'll find someone. Anyone here in Wirral?

I haven't seen its condition of course and he has but if it has been well looked after and is in good condition, I would guess it can be fixed.

He might be a friend but you are paying for the repair!

 

[spartacus]

I haven't seen its condition of course and he has but if it has been well looked after and is in good condition, I would guess it can be fixed.

He might be a friend but you are paying for the repair!

He is coming around today to give it one more go, before I get a second opinion.

Can someone please tell me, because everything points to a thermocouple signal. I am wondering if the thermocouple (which is new and to manufacturers spec) is not getting warm enough...it (looks) in the glass window like it is not fully engulfed by the flame.

So, can someone please tell me...when you release the pilot button, but still on pilot setting (ie. dont turn to main burner), should the pilot stay on, as in...should the solenoid stay depressed? or do I HAVE to turn the dial to main burner to keep the pilot on?

Also, should i be able to hear the solenoid disengage after the thermocouple cools down? ie. pilot light goes out, but solenoid remains engaged, indicating the thermocouple is ok?

Is there a way to test if the solenoid is remaining depressed when the pilot button is released?

 

[Deleted member 120897]

Can someone please tell me, because everything points to a thermocouple signal.

Sorry, but thats against forum rules.

 

[spartacus]

Sorry, but thats against forum rules.

That is probably the stupidest thing I have ever been told? How can it be against forum rules to tell me if its possible to test if the solenoid is activating?

 

[Deleted member 120897]

That is probably the stupidest thing I have ever been told? How can it be against forum rules to tell me if its possible to test if the solenoid is activating?

Well your last answer didn’t make sense, and it was like you were asking for the answer, which is gas related and against forum rules. Nowhere in that did you ask about the solenoid activating. Good luck.

 

[spartacus]

Well your last answer didn’t make sense, and it was like you were asking for the answer, which is gas related and against forum rules. Nowhere in that did you ask about the solenoid activating. Good luck.

I did. I asked...should the solenoid stay depressed. Is there a way I can tell if the solenoid is depressed?

Looking through the glass window...should the end of the thermocouple glow? mine does not. I believe the flame should engulf the thermocouple. Mine does not appear to.

Guy is coming this afternoon, and I am just trying to get some ideas to make the time i am paying for more efficient.

I believe, the problem is that the thermocouple is not getting hot enough, not delivering enough mV to the gas valve, and hence not activating the solenoid. I have already suggested a partially clogged gas pipe, or dirty jet. Which is why I am going to look at it WITH him when he comes. The other option is the gas jet might be misaligned? or he might need to adjust the flame size.

 

[snowhead]

Yes the pilot should stay in when you release the pilot button

 

[spartacus]

Yes the pilot should stay in when you release the pilot button

Thank you all for the advice.

Where we are....He cleaned the boiler. We blew the jet with my compressor. It is a nice strong jet, can be seen through the window.

The boiler still will not stay lit.

It appears that the solenoid is not remaining open. While he was here we even heated the thermocouple with a blow torch to ensure it was getting hot. it is a new glowworm branded thermocouple.

There is electrical continuity (zero resistance) from the body of the thermocouple to the top of the connector between the safety device and the body of the gas valve. It is obviously (impossible?) to test the circuit after the tip of this connection as it is inside the gas valve.

We tried 2 gas valves. The original one and a new one, in case the new one was not compatible.

Can anyone please give me any other reason you can think why the solenoid might not stay open?

 

[Gasmk1]

It’s fairly simple but you need someone who knows older boilers. We cannot tell you anything about the gas side of things.

 

[spartacus]

It’s fairly simple but you need someone who knows older boilers. We cannot tell you anything about the gas side of things.

In the end it was the thermocouple, and a bit of installation error.

After he left, he left a spare thermocouple and a spare gas valve here. I inspected the gas valve, found how the thermocouple connected, screwed it in, ensuring all connections where sound. Fortunately you can see the solenoid plunger from the side of a disconnected gas valve. I heated the thermocouple with a blow torch and was able to get the solenoid to engage.

So then I removed the thermocouple from my boiler, removed the flue safety device, connected the thermocouple at the gas valve, making sure the plastic connector visible from the side of the gas valve was aligned and making contact with the top end of the thermocouple. Then heating the thermocouple with a blow torch, the pilot stays lit.

Reintroduced the safety valve and repeated the same experiment. I could not get a contact and hence no pilot light. I don't think it is the safety device causing the issue; I just think once i screw that in I am not getting a good connection to the plastic connector that carries the voltage to the solenoid. So tonight that is removed. Tomorrow I will sort it out and get the gas engineer to come back and check my work.

Tonight we have heat!

 

[Gasmk1]

so you have removed the safety device, not really a good idea

 

[Ric2013]

so you have removed the safety device, not really a good idea

It's how they do things over here lol.

While I agree the OP should not have bypassed such a device except for the minimum time required to isolate the fault, it must be pretty frustrating to have found the need to do this in order to narrow down the faultfinding process. Hopefully the OP will be alive and well tomorrow and will be able to get the RGI to rectify with safety device back in place.

 

[spartacus]

It's how they do things over here lol.

While I agree the OP should not have bypassed such a device except for the minimum time required to isolate the fault, it must be pretty frustrating to have found the need to do this in order to narrow down the faultfinding process. Hopefully the OP will be alive and well tomorrow and will be able to get the RGI to rectify with safety device back in place.

Surprise...I did live through the night.

And besides... THIS RGI, the last RGI who serviced the boiler, The RGI who did the last gas safety certificate when we bought the house, and anyone else who has ever looked at this boiler in the past 40 years.... left the flue safety device dangling at the back of the boiler. So connected or not... it wasn't doing anything.

 

[Lou]

Hi

Thanks for posting on the forum. Unfortunately it is against the law for you to take the cover off your boiler and do things to it if you are not a qualified Gas Engineer.

Due to this our members are not permitted to advise you on anything regarding you fixing your boiler for your own safety to be honest.

Thanks for understanding. I am going to close this thread now.