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Question for heating engineers/plumbers

Posted: Thu Jan 06, 2011 6:53 pm
by MartDude
I'd be grateful for recommendations for TRVs (15 mm), please. Ideally ones that are likely to be available from Plumb Centre, Screwfix etc - or mail order, if you could also recommend good sites.

Having just had new, draught-free windows fitted, and the multi-fuel stove's (does the central heating) flue replaced, we're finding it almost too warm, especially in the bedrooms. That's the downside of solid fuel - difficult to regulate quickly.

Posted: Thu Jan 06, 2011 7:10 pm
by Samray
Anything the plumbcenter sell should be fine. Main differences will be cosmetic.


until someone says differently

Posted: Thu Jan 06, 2011 7:29 pm
by Willopotomas
Is the water pumped around radiators? My Gran has an old Parkray coal fire with back-boiler/hot water tank. There are two rads plumbed in to it, but the water sort of circulates itself. No pump. :smt001

Posted: Thu Jan 06, 2011 7:40 pm
by MartDude
It's pumped

Posted: Thu Jan 06, 2011 8:08 pm
by Willopotomas
are the rads plumbed in parallel or in series?

Posted: Thu Jan 06, 2011 9:10 pm
by MartDude
Willopotomas wrote:are the rads plumbed in parallel or in series?
AFAIK, parallel. At least, I can isolate one rad without the others being affected.

However, I've just discovered another, more serious issue. There appears to be a pinhole leak in the back boiler, into the firebox. Very small, but noticeable. A friend with the identical stove had the same problem recently, & was able to have it repaired, so I'm hoping ours is repairable. However, as ours is, as it were, built in, it will be a major hassle to remove it for repair - it's plaster-boarded & plastered right up to it, and the new flue liner's been cemented to the stove's flue connector. We could really do without the disruption, not to mention the lack of heating, and the expense. Is there anything on the lines of Radweld that might effect a temporary repair, without harming the rest of the system?

Fault + TRV'S...

Posted: Thu Jan 06, 2011 11:01 pm
by GregD-UK
Hi all,

Most trv's do the job, pegler are a good make, your bedroom's should be 10 degrees cooler than your living spaces. As for the pin-hole in the HEX, that is known as an AR (At Risk) situation. The pin-hole can obviously cause a crack as the metal will expand and the hot water can empty out of it and be a very bad scenario to deal with. Most HEX's can have a small weld put in, but, long-term, new HEX required :smt009

A good GasSafe Engineer could sort it out for you... Cost is dependable on how well you know him...

Posted: Fri Jan 07, 2011 6:18 pm
by MartDude
Sorry, Greg, what's a HEX? Heat exchanger? I'm talking about a multi-fuel stove with a back boiler - a sort of water jacket around the stove.

Dual Fuel...

Posted: Fri Jan 07, 2011 6:45 pm
by GregD-UK
Hi all,

Yes, a small pot in the back (HEX) as we call them in the trade :smt002 You could put in 2litres of rad weld. I (Gas Engineer) would always recommend to take out and repair properly or replace. As I said before, the classification of AR (At risk) for this particular fault. I can understand you reluctance to mess since you have had some remedial work done recently. You have to weight up the expense and inconvenience OR no heating and hot water my friend..... As always, a competent local engineer will give you options. Radweld will be a tempoary fix, as that is all radweld is :smt002

Posted: Sat Jan 08, 2011 12:41 am
by MartDude
Greg - my apologies if I seemed to appear disparaging of your expertise - was just hoping to stave off the inevitable until the end of winter. We were planning on replacing our central heating system with an oil-fired one later this year (no mains gas here) - but we'd rather not do it right now

Oil or LPG...

Posted: Sun Jan 09, 2011 7:23 pm
by GregD-UK
Hi all,

Well, as I said, just chuck some radweld in and hope it lasts till after this lovely winter :smt004 I would suggest you look at an LPG boiler. Oil is dirty and almost as expensive as LPG! Much cleaner to work on LPG :smt002 Depending on how far out you are from civilization that is.

Re: Oil or LPG...

Posted: Sun Jan 09, 2011 8:10 pm
by MartDude
GregD-UK wrote:Hi all,

Well, as I said, just chuck some radweld in and hope it lasts till after this lovely winter :smt004 I would suggest you look at an LPG boiler. Oil is dirty and almost as expensive as LPG! Much cleaner to work on LPG :smt002 Depending on how far out you are from civilization that is.
Unfortunately, we're miles from a mains gas supply, so it'll have to be oil, or LPG tank. LPG would be convenient, as we have an LPG hob. We've got a local heating engineer, recommended by a friend in the heating equipment trade, coming to do a survey and give recommendations.

BTW, is this stuff likely to be any good for a temporary fix for our problem?

http://www.google.co.uk/products/catalo ... CB8Q8wIwAA#

http://www.plumbnation.co.uk/site/ferno ... ak-sealer/

Many thanks, Greg. Shame you're not closer

Sealer...

Posted: Sun Jan 09, 2011 8:51 pm
by GregD-UK
Hi all,

Yes, fernox or sentinell sealer is ok. Go for 2 ltrs :smt002

Posted: Mon Jan 10, 2011 6:22 pm
by MartDude
Thanks Greg

2 litres of which one? This
http://www.plumbnation.co.uk/site/ferno ... r---500ml/

or this?
http://www.plumbnation.co.uk/site/ferno ... r---290ml/

If I use this Image how do I apply it - into the header tank? The super-concentrate is applied via a radiator air-bleed thing - but I'm not sure if ours will screw right out.

Very grateful for your help on this, Greg - only ever done anything like this with cars.

Posted: Mon Jan 10, 2011 11:41 pm
by GregD-UK
Header Tank, but, drain down a rad, so it goes round the system and not just sit in the tank :smt002