Long Term Health of a Microbore Heating System

[Jerry]

Hi All,

I just wanted to get some opinions on the long term prospects of a microbore system. I am personally in favour of them. I am very happy to instal a 'point to point' system with a nice manifold. As long as the system is sealed, filter, well inhibited and maintained, then it should be durable in the long term.

I understand many people will say that the homeowner will neglect it, the property will change hands, the system will be abused etc etc and that will result in its quicker demise.

However, as a metaphor, if you own a car, then it is your responsibility to understand it and take care of it. You need to check the tyres and top up the fluids at a minimum. We nearly all have cars and we nearly all have heating systems.

And can we have more constructive comments than "it should all be done in copper, like a proper plumber because that's how I was taught back in the day".

 

[Millsy 82]

If its looked after it's good but as you said if it's not looked after it can be a nightmare.

I still look after quite a few on 8mm that are 30+ years old and as good today as they were 30 years ago. But we don't have much of an issue with sludge round me.

 

[Jerry]

But we don't have much of an issue with sludge round me.

How do you not have sludge?

 

[Millsy 82]

Soft water I think. But very rarely come across a system that sludged up it needs a power flush.

 

[Jerry]

Soft water I think. But very rarely come across a system that sludged up it needs a power flush.

I always thought the bulk of sludge with rust from the inside or radiators (i.e iron) and not limescale.

 

[Millsy 82]

Well from my experience the harder the water the worse the sludge. I lived in the cotswolds 1 side of the hill was Severn trent the other Thames the Thames which was really hard water was horrific for sludge the Severn trent not as bad but still bad then down here it's hardly a problem at all.

 

[Jerry]

Well from my experience the harder the water the worse the sludge. I lived in the cotswolds 1 side of the hill was Severn trent the other Thames the Thames which was really hard water was horrific for sludge the Severn trent not as bad but still bad then down here it's hardly a problem at all.

Well, you learn something new everyday. I wonder if the ph of the water due to the limescale has something to do with it aswell.

 

[Chalked]

My own house is copper microbore. Fitted in the early 90s and it’s clean as a whistle. Sealed system from new.
The ones that are bother, generally have open vent and with poor pipe layout, they get oxygenated water, which is the ,sin cause of sludge and corrosion.
Then there’s plastic!!! This had big problems early on, with non barrier pipe. And even with new installs, it can still cause blockages, as the deposits seem to flake off and block up where there is an insert.
So..... copper microbore, ok. Plastic awful! But that’s just my opinion.

 

[whatsthenews]

interesting. Thanks Jerry

 

[hammers4spanner]

No sludge where I am either just black crap

 

[Best]

Microbore just can’t handle long runs and also struggles to heat large radiators.
And the plastic microbore is a lot worse due to having thicker walls, so actual internal bore much smaller.
I don’t use copper or plastic microbore but I can see the advantage of using it on very short runs to some radiators, feeding it in one piece

 

[Jerry]

Microbore just can’t handle long runs and also struggles to heat large radiators.
And the plastic microbore is a lot worse due to having thicker walls, so actual internal bore much smaller.
I don’t use copper or plastic microbore but I can see the advantage of using it on very short runs to some radiators, feeding it in one piece

I haven't found it to be a problem with large radiators on a point to point system. Maybe this would be more pronounced with a normal radial style system.

I do agree that the bore size of plastic pipes is generally smaller because of the insert. This is why I am trying to use Buteline because they claim they have the highest bore size.

 

[Best]

I haven't found it to be a problem with large radiators on a point to point system. Maybe this would be more pronounced with a normal radial style system.

I do agree that the bore size of plastic pipes is generally smaller because of the insert. This is why I am trying to use Buteline because they claim they have the highest bore size.

Plastic pipes are not only at the insert a smaller diameter, but obviously entire pipe is due to needing to be much heavier walled than copper.
It is the long length of runs that is the problem.
A real test of a system is on full demand for the radiators, like severe winter days when you find the rads with undersized or badly balanced pipework not able to fully heat and the middle and lower part of rad cool.
I notice this with systems that have mixed pipework to rads (microbore and 15mm).

 

[townfanjon]

Chez TFJ , built in around 1990 , 8 mm microbore, was open vented up to around 7/8 years ago , system boiler fitted then , no bother !!

 

[whatsthenews]

I haven't found it to be a problem with large radiators on a point to point system. Maybe this would be more pronounced with a normal radial style system.

I do agree that the bore size of plastic pipes is generally smaller because of the insert. This is why I am trying to use Buteline because they claim they have the highest bore size.

Sorry, please can you explain what you mean by "a point to point system"? We're about to have our 1 pipe system ( a combi on what was a backboiler system originally) repiped and the engineer is talking about 22mm copper with manifolds and then 10mm plastic to the radiators so he can channel the pipes into the wall behind the radiators. Just had a new boiler fitted so the system's all been flushed and inhibitor added and now has a filter.

 

[Rob Foster]

Sorry, please can you explain what you mean by "a point to point system"? We're about to have our 1 pipe system ( a combi on what was a backboiler system originally) repiped and the engineer is talking about 22mm copper with manifolds and then 10mm plastic to the radiators so he can channel the pipes into the wall behind the radiators. Just had a new boiler fitted so the system's all been flushed and inhibitor added and now has a filter.

channel pipes into wall, hmmm
put them into plastic conduit chased into the wall to allow exp and contraction. centralheatking

 

[OffshoreGas]

Surely pipes should just be sized correctly? Smaller pipes required greater velocities/have bigger pressure losses than larger pipes varying the same volume. Smaller pipes have a greater surface area for a given cross sectional area meaning greater heat loss too. Generally they seem more fragile and inherently more likely to become blocked by debris. The greater velocities however are more likely to reduce the build up on pipe walls. Personally I think the cons outweigh the pros with microbore.

 

[Rob Foster]

Surely pipes should just be sized correctly? Smaller pipes required greater velocities/have bigger pressure losses than larger pipes varying the same volume. Smaller pipes have a greater surface area for a given cross sectional area meaning greater heat loss too. Generally they seem more fragile and inherently more likely to become blocked by debris. The greater velocities however are more likely to reduce the build up on pipe walls. Personally I think the cons outweigh the pros with microbore.

That is a very well considered opinion off shore we should all be impressed with it ...thank you....centralheatking

 

[whatsthenews]

channel pipes into wall, hmmm
put them into plastic conduit chased into the wall to allow exp and contraction. centralheatking

I phrased it wrong. I meant pipes in plastic conduit chased into the walls.

 

[Rob Foster]

I phrased it wrong. I meant pipes in plastic conduit chased into the walls.

Thats better, I write specifications all the time its very easy to miss a crucial detail out , you are excused
centralheatking

 

[Jerry]

Sorry, please can you explain what you mean by "a point to point system"? We're about to have our 1 pipe system ( a combi on what was a backboiler system originally) repiped and the engineer is talking about 22mm copper with manifolds and then 10mm plastic to the radiators so he can channel the pipes into the wall behind the radiators. Just had a new boiler fitted so the system's all been flushed and inhibitor added and now has a filter.

'Point to Point' heating involves manifolds and has a pair of pipes (flow and return) from the manifold going directly to each radiator.

 

[whatsthenews]

'Point to Point' heating involves manifolds and has a pair of pipes (flow and return) from the manifold going directly to each radiator.

So in approx' 100 m2 2 storey, 3 bed, 2 reception house would there be a manifold for the ground floor and one for upstairs? 22mm copper going from the boiler to/from the manifolds and microbore to and from the radiators?