Cracked Stove Glass

[blackrose]

I lit my stove last night and I noticed a crack in one of the door windows running from the top-left corner to the middle of the glass. I'm fairly sure I didn't hit the glass with anything or slam the door. Next time I looked about 20 minutes later the crack had stretched right across the glass to the other side. Why did this happen? I thought the glass was already tempered. (The stove is a Morso Panther http://images.google.co.uk/imgres?imgurl=h...LF:en%26sa%3DN)

Edited December 9, 2008 by blackrose

[Tim Doran]

I lit my stove last night and I noticed a crack in one of the door windows running from the top-left corner to the middle of the glass. I'm fairly sure I didn't hit the glass with anything or slam the door. Next time I looked about 20 minutes later the crack had stretched right across the glass to the other side. Why did this happen? I thought the glass was already tempered. (The stove is a Morso Panther)

 

I should think it was either caused by heating a cooling over an extended time period or from vibration and bumps on the boat.

 

I think that new glass is about £20

 

Tim

[Gibbo]

I lit my stove last night and I noticed a crack in one of the door windows running from the top-left corner to the middle of the glass. I'm fairly sure I didn't hit the glass with anything or slam the door. Next time I looked about 20 minutes later the crack had stretched right across the glass to the other side. Why did this happen? I thought the glass was already tempered. (The stove is a Morso Panther)

 

Absolutely no use to you whatsoever but......

 

How odd. I had exactly the same thing with a Morso Squirrel and then a month later with the boat window nearest the chimney (10mm laminated and tempered). Never did work out what caused it.

 

Gibbo

[blackrose]

The cracked glass is still usable, but I might give Morso a call and ask them why this happens before ordering a new window.

[kayDee]

This can happen if the glass is fixed solidly to the metal surround of the door. When the metal expands and contracts with the heat - I think the glass takes the brunt of it - being the weaker of the two. They may well expand and contract differently from each other and something has to give!

We did this once and accidentally glued the rope seal too tightly into the metal door frame - so the glass was completely unable to flex in the frame...

Kay

x

Edited December 9, 2008 by kayDee

[Richard T]

Remember that the crack is a potential source of combustion gasses entering the boat and they include carbon monoxide. So for your own safety replace ASAP and check that your CO detector is working.

[blackrose]

This can happen if the glass is fixed solidly to the metal surround of the door. When the metal expands and contracts with the heat - I think the glass takes the brunt of it - being the weaker of the two. They may well expand and contract differently from each other and something has to give!

We did this once and accidentally glued the rope seal to tightly into the metal door frame - so the glass was completely unable to flex in the frame...

Kay

x

 

Yes I agree, but since this expansion & contraction has been happening for the last 3 years (when I installed the stove), one would have thought that either the glass would crack straight away or not at all. Perhaps the glass becomes weakened over time until it finally cracks?

 

Remember that the crack is a potential source of combustion gasses entering the boat and they include carbon monoxide. So for your own safety replace ASAP and check that your CO detector is working.

 

Thanks. There's no visible gap in the cracked glass and I'm sure the gap it's a lot narrower than the door seals etc. I think most gaps in stove door seals & windows generally allow air into the stove rather than combustion gasses out, but I will keep an eye on it to make sure the crack doesn't widen.

[alan_fincher]

Whilst you may get away with it for months, it's also possible that the whole lot may cave in on you at an unexpected time.

 

I believe you have diesel heating as a backup, so maybe not too critical to be without it for a day or two, but if it was me I'd want to have a replacement available on the boat, even if you don't fit it yet.

 

If it's secured by nuts on threaded studs on the back of the door, I'd start tipping something like PlusGas on it now, in the hope that it will start to work on the threads, and you'll be able to remove the nuts when you need to.

 

Alan

[GSer]

After having two glasses break in my stove over my first winter aboard I enquired the same and was told it was the use of firelighters (or possibly too many of them) that caused the cracking, sounds very much like BS to me, but I must admit, after reducing the useage of firelighters, glass consumption has dropped to one every couple of years.

 

I bet some clever bod on here knows

 

Paul

[saltysplash]

Whilst you may get away with it for months, it's also possible that the whole lot may cave in on you at an unexpected time.

 

I believe you have diesel heating as a backup, so maybe not too critical to be without it for a day or two, but if it was me I'd want to have a replacement available on the boat, even if you don't fit it yet.

 

If it's secured by nuts on threaded studs on the back of the door, I'd start tipping something like PlusGas on it now, in the hope that it will start to work on the threads, and you'll be able to remove the nuts when you need to.

 

Alan

 

 

I also had to take a pr of molegrips to undo mine..rock solid

[sociable_hermit]

I've just stuck some copper slip round the threads to stop mine from seizing up, just in case I ever need to replace the glass.

 

Worried I've over tightened the nuts now, though!

[DaveR]

Mine cracked when starting from cold. Has the door tightly shut and have been told that as the door was unable to move when heating up - the glass gave way.

 

I now let the fire body warm up before clamping the door tight shut.

[madcat]

We replaced the glass on a friends stove with a sheet of metal because the cracked glass broke.It had been cracked for ages. Several years on the metal sheet is still there because it is safer when left alone and less vunerable to getting bust.I imagine it would be not too difficult to remove the frame because I used Threadguard anti sieze compound when reassembling.

[blackrose]

Whilst you may get away with it for months, it's also possible that the whole lot may cave in on you at an unexpected time.

 

I believe you have diesel heating as a backup, so maybe not too critical to be without it for a day or two, but if it was me I'd want to have a replacement available on the boat, even if you don't fit it yet.

 

If it's secured by nuts on threaded studs on the back of the door, I'd start tipping something like PlusGas on it now, in the hope that it will start to work on the threads, and you'll be able to remove the nuts when you need to.

 

Alan

 

Thanks Alan. I'll order a new glass today. Is PlusGas the same sort of thing as WD40? I've got plenty of that onboard.

 

Yes, I have an erberspacher, a 2.5kw electric radiator (on shore power), and also a 2.3kw paraffin heater, so I think I'll probably be ok!

[alan_fincher]

Is PlusGas the same sort of thing as WD40? I've got plenty of that onboard.

Plusgas is specifically a "dismantling fluid", or what in old days might have been termed a penetrating oil.

 

In my experience, WD40 is trying to be too many things, so whilst it is good at many of them, it's not the best.

 

I've not seen Plusgas for a while, and don't think I have any. But it worked better than other penetrating oils, such as "3-in-1"'s offering.

 

Mental note to self - ask when next in my favourite hardward store.

 

WD40 may do it for you, though....

[Scotty]

Plusgas is a better penetrating oil, where as WD40 is a good all rounder (penetrating, lubricating, degreaser)

In other words, try WD40 and if it doesn't work look for plusgas

 

 

Edit: Oh, Alan beat me to it!

Edited December 10, 2008 by Scotty

[blackrose]

Update:

 

I just called Morso and a guy from their technical dept told me that stove glass is considered a consumable service part. They do crack occasionally and he reckoned that 3 years is a reasonable lifespan. He also said it has nothing to do with the use of firelighters.

 

Stove glass isn't covered under the Morso warranty: http://www.morsoe.com/uk/Warranty/Warranty/

Mind you just about everything seems to be listed under the exclusions - I don't know why they don't just say Exclusions: Stove!

Edited December 10, 2008 by blackrose

[Leepers]

Ours cracked last winter during a cold spell, The fire was not lit, but the door was locked, I think the door distorted enough to crack the glass with the metal contracting and putting pressure on the door, we leave the door open now so far no more problems

[ditchcrawler]

Plusgas is specifically a "dismantling fluid", or what in old days might have been termed a penetrating oil.

 

In my experience, WD40 is trying to be too many things, so whilst it is good at many of them, it's not the best.

 

I've not seen Plusgas for a while, and don't think I have any. But it worked better than other penetrating oils, such as "3-in-1"'s offering.

 

Mental note to self - ask when next in my favourite hardward store.

 

WD40 may do it for you, though....

I wanted some "Plus-gas" last summer while in Braunston and when I went to some of the well known equipment outlets by the cut got some strange looks and the offer of WD40 when I asked for it. In the end I had to go into Daventry and managed to get some at the car accessory shop.

[rrt2]

Don't bother to buy anything to loosen stuck nuts you have a tank full of diesel to do it with, just a drop on the threads and leave it to soak and creep along.