Gas valve cleaning (1 Viewer)

Feb 22, 2011
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My Dometic fridge was becoming difficult to light on gas so I decided to remove it and clean the valve out.
Is there anything else I should be doing maintenance wise whilst it's out ?
I can't test it until it's reinstalled :eek:
The pipework looks rather corroded.
Also, the foam seal to hab side has perished, can I just replace it with domestic draught excluder ?
Oh, happy new year as well (y)
 
OP
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Figaro
Feb 22, 2011
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Oh here's a photo
IMG_20180101_094100265.jpg
 
Aug 6, 2013
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I was hoping you meant 'jet' rather than 'valve':). Give the chimney a brush out too after lifting out the baffle from the top. Pipework, by which I assume you mean the fridge component pipework rather than the gas supply, corrodes about 10 minutes after the fridge is first installed - so they all look like that. The foam you suggest will be fine. It's worth checking the condensation drain is clear - that's the pipe from just below the freezer (inside the fridge) that ends up in the polythene trough in your photo. The trough can be cleaned too.

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OP
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Figaro
Feb 22, 2011
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Yes, sorry the jet I vac out and it's the fridge pipe work that's corroded.
I'll have a look at vacing the flue
There is a bit of water in the trough so looks like it's draining free.
Thanks
 
Aug 18, 2014
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Is there no way you can test it with it out ? 12 v from battery ;240 v lead with plug on length of rubber tube for gas ? Far better if you can as then you can confidently refit it
 
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Figaro
Feb 22, 2011
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Is there no way you can test it with it out ? 12 v from battery ;240 v lead with plug on length of rubber tube for gas ? Far better if you can as then you can confidently refit it
I might try that, thanks for suggesting

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Nov 4, 2011
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I would remove the jet holder completely by undoing the nut (green arrow) then remove the screw (red arrow) and then remove the jet completely, it's a pressed metal top hat that fits inside behind the nut ( green arrow)
Also out of interest because I've got to take my fridge out, did you disconnect the gas feed pipe to slide your fridge out and if so, where did you disconnect it.
IMG_0050.jpg
 
OP
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Figaro
Feb 22, 2011
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@Manic Yes, I had to disconnect everything to get it out, gas connection was through top vent on the left, 12 volt and 240 from under the hob by lifting it a few inches, there was no slack in the cables to move without disconnecting. Quite fiddly to do but I`m hoping worth it.
I`ll do what you suggest next weekend and I`m buying a bottle brush for the flue.
When it`s out do I just clean the jet with I soft brush and vac ? I think I read not to poke anything down the jet
 
Nov 4, 2011
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When you get the jet out,( be careful as the jet is only thin metal) just blow it clear and tap the jet block on something solid to knock out an muck.
IMG_2815.jpg

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Oct 29, 2008
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The corrosion is caused by the condensation pipe filling the plastic catching container over time.
I removed ours and extended the thin plastic tube through the grill to drip outside.

When the jet assembly is out you can get a fine strand of copper wire to clean the jet hole. be careful you dont lose the small disc that has the jet in the middle. As shown above
 

joeo's

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Dec 23, 2016
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I'll offer my tuppence worth from my experience. I'm not trained on Gas or Gas Appliances and comments are based on my own experience, only, and should be considered only on that basis.

When you have disconnected the copper pipe from the Burner Unit (at the green arrow in Manic's diagram), have a look at the end of the gas supply pipe, as well as the jet. I have found a build up at the end of the pipe. If so, a toothbrush should dislodge it.
CARE ... I have turned on the gas supply for a few seconds WITH ALL LIGHTING/IGNITING turned OFF, to blow out any loose debris from the pipe, before reconnecting it to the burner unit.

From the photo, everything seems to be in good condition, so my First Guess would be a partially blocked jet as described in earlier post.

**CARE is required, as suggested in earlier post, because the jet is delicate and the size of the hole is critical for safe operation. I'd use a toothbrush and nothing firmer and a good blow (of your breath) to clear the hole of the jet. Handle the jet very carefully avoiding the use of any tools that might distort it. Replace it carefully making sure that it is sitting correctly, before reconnecting burner to gas supply pipe.
My Second Guess would be build up of debris at the end of the pipe as described in second paragraph above
My Third Guess (-unlikely however, because of the good looking condition of the burner unit) would be the possibility that the thermocouple might not be located correctly in the flame and takes a bit longer to heat up enough to operate the gas safety-cut-out valve.

TAKE GREAT CARE WHEN WORKING ON GAS and check all joints for leaks when you're finished working on it.
I'm not familiar with the law in the UK, but only fully certified and suitably registered Gas Engineers are allowed to work on gas systems in Ireland.

The Flame should be BLUE not Orange/Yelow.
If not burning with a Blue flame, it is not safe and Carbon Monoxide could be produced.... CO spells ***DANGER*****
Hope you get sorted.
 
Aug 6, 2013
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If you intend removing the jet itself (l wouldn't advise it) then buy a new one before you start. They're aluminium and compressed within the jet holder.
 
OP
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Figaro
Feb 22, 2011
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Thanks for all the replies, I think I will just use a bottle brush on the flue, vac out again and reassemble and see if it`s worked. Hopefully it will be ok, otherwise I`ll be looking at removing again and dismantling the jet etc.
 

joeo's

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Dec 23, 2016
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We've probably made you nervous about the task. Sorry.

It is probably worth saying, however, that if you clean the flue chamber, without firstly removing the burner unit, you may well cause debris to fall into the burner and make the situation worse, rather than better.

I came across this video on you tube

which explains how to remove the burner, check the gas jet and reassemble, which may be of interest.

The gas jet does not usually fall out as easily as in the video, in my experience. However, you can see if its blocked without removing it. I'd use a toothbrush or paint brush to gently brush it clear, if blocked, even if it stays in the burner. Re-using it has never caused a problem for me, but using a new one may be best practice, I don't know about that. If using a new one, you must be sure that it is the correct one for the fridge i.e. is correct size, shape and has the same size hole. The Engineer in the Video appears to re-use the old one, after checking the hole. Don't forget to also check the gas pipe for build up.

I would always do this check of the burner etc. through the bottom vent and never bother to take the fridge out.

I push a piece of wire (e.g. wire clothes hanger) through the flue chamber when the burner is off, to clear out any rust or debris. A bottle brush is probably better, if it it long enough.
Good luck, whatever you decide.

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Nov 4, 2011
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Thanks for all the replies, I think I will just use a bottle brush on the flue, vac out again and reassemble and see if it`s worked. Hopefully it will be ok, otherwise I`ll be looking at removing again and dismantling the jet etc.

It's such an easy job to clean the jet out, it would be silly not to do it.
The jet will just fall out, well it did on my 2001 version ( actually nearly lost it once when it fell out when I removed the jet block)
 
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Figaro
Feb 22, 2011
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Thanks @Manic, and @joeo's I watched the video and it was helpful, I just wish my fridge was that easy to remove !
The jet that drops out of the burner, does it have to go back in a particular way round ? Or will it be obvious on removal which way round it goes. My job for the weekend.
Thanks
 

joeo's

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Dec 23, 2016
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Agree wit Manic. It is a very easy job.

The jet is circular and fits snugly into the burner. It may or may not have fallen out when the pipe is disconnected.
Just see that it is in place and "pointing" into the burner -as shown in Manic's diagram showing the Jet, Post #9
When the pipe is reconnected, it compresses the jet slightly into burner.
JOB Done!
-Leak checks, if gas supply was disconnected at top of fridge.
-BLUE flame check?

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OP
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Figaro
Feb 22, 2011
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My fridge saga continues....
I removed the burner assembly, the jet didn`t drop out and I decided not to force it out, I just blew through it.
Got a bottle brush on the flue and vac up, reinstalled and turned on.
The light flashed and clicker heard but fridge didn`t light. The flashing/clicking slowed after some time and even stopped for a few seconds, then re-started. After removal again / checked position of sparker and thermocouple and reassembled, eventually it lit and worked for an hour before I turned it off. Tried to light half an hour later and nothing, no clicking, no flashing, wouldn`t light.
Could it be a failed thermocouple ? or something else.
Thanks
 

Silver-Fox

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Sep 5, 2014
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Check and clean all the electrical connections as well.
A failed thermocouples will just prevent the gas valve staying open and not stop an initial light.
 

joeo's

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Dec 23, 2016
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No flashing of the ignition suggests an electrical problem.
Possible causes include Low battery voltage, faulty switch or a break or bad connection in the wiring circuitry.
If the fridge ran for an hour with a Blue flame, the gas part of the system is probably ok.

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OP
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Figaro
Feb 22, 2011
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I`ll take it out again tomorrow and check the wiring connections.
Battery voltage is ok but I can`t check the flame when it`s installed, there is no lower vent to look through as it`s in the floor and not accessible and I don`t have the facilities to rig up a benchtop gas supply.
Thanks for input, if I can`t find anything wrong and it`s still not working I`ll try and find a repair workshop
 
OP
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Figaro
Feb 22, 2011
9,796
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Newcastle under Lyme
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Just by way of an update, Wiring connections checked and all re-assembled now and fridge working nicely on gas :)
So I`m happy.
Thanks for all tips and help.
For those that have not serviced their fridge, it is quite straight forward, the hardest part for me was getting the fridge out as there was no slack in the electrical cables, but once it`s out it`s an easy job.
 

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