My Inefficient Micro Bore Central Heating System

[widescreen]

Folks, I inherited a Micro Bore System in my house. Boiler etc works fine,
all single rads get hot, however, the three long double rads , one upstairs and two in the lounge are the problem. All get reasonably hot on one side and but the other part is only lukewarm. Venting makes no difference. Various people have given different opinions ,from balancing the system and sludge in the system.Some said put a new system in. Some neighbours have the same system,some work perfect ,some are similar to mine. A plumber I have spoken to lately and who should call this week is suggesting that a solution be injected into the sealed system which should break down the sediment etc... Anyone agree with this or have a bit of advice they can give me. If not I'm going to freeze again this winter!

 

[PEDANTICVINDICTIVEMAN]

Firstly are the pipes big enough, if the rad output is over approx 6000 btu and fed with 8mm pipe, and the 8mm pipe has a long run from the manifold or main run, then it will struggle to work from day one, secondly, are the radiator valves the old twin entry (valve with two pipes at one end only) type, or single entry (valve at each end) type ?

 

[Rincewind]

microbore sucks! Having it cleaned out and treated with fernox or sentinel X100 is the best thing to do. If still not working take off rads and flush thru with hose pipe. If still not working get a power flusher on the case.

 

[ChrisR]

microbore sucks!

I wish it did, then the bloody water would go through it.

 

[PEDANTICVINDICTIVEMAN]

Nothing wrong with microbore if fitted correctly, it's the cowboys that have caused the problems using too small pipe for long distances and then incorrect vent and feed arrangements sludging system.

 

[widescreen]

Lads,thanks for comments so far . I have a plumber coming(so is xmas!!)
and he is going to take a look. He was talking about putting a solution in the system,maybe I should get him to take off the two problem rads and flush them out as well. He's a good plumber who knows what he's doing so I'm hopeful we'll get it sorted. At least it doesn't get as cold here in the West of Ireland as it does over in the UK!!

 

[widescreen]

Folks,

Just one final question on this subject.

My microbore system is 25 years old at least. If I put FERNOX in the system is there a risk I could end up worse off than before! i.e. would the sludge etc relocate and possibly cause more probs...

Would appreciate response before I activate the plumber...

Cheers

 

[DP]

The problem, like some have already suggested is that the rad is not getting the quantity of water it needs. Answer would be to clean the system and possibly instal 15mm to the larger rads or investigate microbore runs and ensure bore and length are correct for the load placed at the end of the pipe.

Radiator hot at the inlet would suggest insufficient water flow be it due to sedimentation, damage to pipe, teeing another rad off the microbore to name a few.

 

[widescreen]

Appreciate your reply. However, the only option I have is either to leave as is and put up with the 55-60% I'm getting.I got the wall insulated earlier this year and it has improved the heat in the house to acceptable level. I was hoping by inserting the system with FERNOX it may improve it to somewhere around 75-80% . My query now is really whether FERNOX could leave me worse off as the system is so old. Is it worth doing!!

Help pls...

 

[PEDANTICVINDICTIVEMAN]

If your getting the required room temperatures 21 lounge, 18 beds and hall 22 bathoom why worry, half hot rads is only a mind set, stick in some Sentinel X400 and follow instructions or get someone in to powerflush and see how you go.

 

[widescreen]

Thanks very much for that. BTW is Sentinel better than Fernox ?

By doing that no danger of moving sediment etc to make things worse??

 

[PEDANTICVINDICTIVEMAN]

I use Sentinel as it is Recommended by Worcester boilers, so as I tend to fit a lot of there combi's that is what I use, cant comment on fernox as I dont use it.

 

[citizen]

widescreen,
I had similar problems when I moved to my present house.

All rads in the house were fed with 10mm pipe from a manifold fed with 22mm. The 2 large double radiators in the living room only heated up properly once other rads closed down.
I powerflushed, removed and cleaned the manifold which only helped slightly.
The problem was only resolved when I replaced the 10mm pipe with 15mm (edit. to the 2 double rads, not all rads).

Regards

 

[widescreen]

Thanks for that information Citizen.Also thanks to all other people for their assistance.

Think I finally know where I stand on this issue.