Gun Barrell piping in central heating

frash

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I recently bought a house built in the 50s.
The rads in it look old (they're very thin) & don't give out much heat unless you're on top of them.

I know I'm gonna need new rads but I've heard stories about "gun barrel" pipes - how do I know if I have them or not?
 
Gun barrel pipes are a silvery colour. More modern pipes are copper. If you look at the point where the radiator joins a pipe into the floor you should be able to see which it is. Scrape the paint off the pipe if its painted. Your pipes and rads may be silted up and efficiency would improve if you got them flushed out. But this would be a temporary measure. If you have Gun metal pipes you will have to replace them with the radiators, modern rads cant be jointed to gun metal.
 
I have gunbarrell piping and modern rads connected to them, there's a gunbarrell to copper fitting available.
 
Newer rads can be fitted to GB pipe. I do agree that you should a cleasing agent through your system for a few weeks and then flush it out. The problem with GB pipe is that it rusts from the inside out and if you find you get one leak you can bet more will follow, however if they are in good condition i would def leave them in, when the system has been flushed you should add an inhibitor to protect the system from rust. I would also get new rads, they are throw out alot more heat.
 
Thanks for all the relpies.
The pipes deffo aren't a silvery colour so I guess they're copper.

I'll find out for sure when I get the rads replaced.
Until then it's a nice warm fleece & light the fire!
 
If the pipes were put in in the 50s/60s, chance are a lot of damage internally from rust will already have occurred. I'd recommend getting rid of them, especially the underfloor ones as these won't be insulated either so they will be loosing heat. Much easier in effect to replumb the house rather then have old pipes onto new radiators, it'll save you in the long run as gun barrell will evenentually leak
 
Thanks Mpsox
The house was built in the 50s but I've no idea when the central heating was put in.
By the looks of it though the piping is copper - I'll just need to get the rads replaced.
 
Finally getting around to replacing the rads in the house (delayed due to also getting an extension).
Anyway although the pipes going from the floor to the rads are copper the builders have discovered that the pipes they are joined to are indeed gun barrell.

They need to get the plumber to look at it before giving me a price for replaing them but does anyone know how much I can expect to pay to replace the gun barrell?

I've already got a price to just replace the rads but this was before the new discovery.

House is a 3 bed semi-dee.
 
HI Flash, I am in the same position.. we are converting from an oil burner to gas burner and have been advised to replace the gun barrell piping and then obviously change the rad's too. We wont be doing this until the summer so havent started to price it yet but am interested to hear if anyone has any advise. House is approx 1300 sqft.
 
Hi Qbot,

I should know more about prices after the weekend hopefully but I was just hoping to get an idea of the potential costs before hearing it from the builder & his plumber.
 
We eventually got rid of the gun barrel in our house recently. It has a certain life expectancy (25 to 30 years max I think?) but it WILL leak eventually. If you're getting other work done, get it replaced now. The leak can start gradually, and possibly in more than one place, and it can cause terrible damage over time (carpets, wooden floors, walls, general dampness building up over time, etc). The price will depend on how extensive it is, and how easy it is to get at (is it buried in concrete floors?). Our plumbers recently charged us €400 per day for two lads and it took them nearly 2 days, plus materials. More expensive that I anticipated, but DON'T be tempted to turn a blind eye to it. The plumber even mentioned that some insurers will not cover damage caused by leaking gun barrel, so beware!
 
Thanks for the reply Oopsbuddy - it give me a ball park price to base ours on.
I don't think any will be buried in concrete - just under the floor boards upstairs & downstairs.
 
Oh dear! we have concrete floors downstairs and usual floorboards upstairs. But plan on getting plumbing done first thing while upgrading the house. As you said, better to get this done - it will save cost in the future - house is about 28yrs old. €400 a day for 2 days doesnt sound too bad.. however, I am guessing that materials are very expensive. Oopsbuddy -if your plumber was in dublin, can you send me a private msg with his details please.
 
I don't know that materials will be overly expensive - I'd imagaine (in my limited plumbing knowledge) that they will just replace the gun barrell pipes with those fliexible pipes that they use these days with copper coming up to the rads.
 
Sorry, they are not Dublin prices, and so as not to mislead anyone, the 2 days was for a relatively small amount of pipework (the rest of the house had either been replaced before (should have got all of it done!!) or was copper pipe installed correctly in later extension). Plumbers will give a better guide to Dublin prices, and the time required will depend on the work involved.
 
Ref Steel or copper?
Take a fridge magnet and place it aginst the pipe.

If it attatches to the pipe it is steel pipe. One of two types of steel pipe.
If the magnet attatches and it is the same colour and outside diameter as copper pipe then it is "copperclad" this copper covered light gauge steel pipe was used some years ago during a copper shortage. It should certainly in my opinion be replaced. Just google copperclad pipe

The much heavier gauge externally thicker Gun-barrel steel pipe is specified for systems in the vast majority of commercial or industrial buildings. All jointed to the latest modern radiators. They may be seen through the glass fronts of office blocks in our cities.
Are all the consulting engineers wrong? No.

If a heating system is designed and installed correctly gun-barrel will last for very very many years.

Of course steel pipe-work will corrode externally if mains to a remote boilerhouse are buried poorly protected in the garden. as was the case with some Dublin housing developments. (These were replaced with stainless steel or copper)

Steel pipes may be found corroded externally near radiators below a neglected and leaking radiator valve packing gland.

It may also corrode internally if air is permitted to enter a system.

The only domestic steel pipe-work that I have had to replace were below ground external boiler mains and corroded risers to leaking radiator valves.

If the boiler is adjacent to or within the house it is most unlikely that all of your steel pipe-work will have to be replaced.
Engage an experienced, competent plumber and he will advise. He will also be able to cut and thread a pipe where neccessary. See radtesting.com or plumbersdiary.com
 
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