Posted by: @deltona

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But it isn't fact, it's just your unprofessional opinion.

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If, by that, you imply that @jamespa is not a plumber or heating engineer by trade, you are correct.

If, by that, you imply that the track record of @jamespa's advice on the subject of heating systems is substandard, there are a lot of members here who would argue with you. Many here have heard him freely admit he doesn't do this for a living, have still taken his advice and have seen running costs come down and comfort go up. He might not be able to do that for everyone, but the number of times he's been successful speaks to a very high level of professionalism.

Posted by: @jamespa

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@deltona 

I did draft a long point by point response but on reflection it isn't worthwhile.  Suffice it to say that I find some of your wording quite offensive and out of kilter with the tone of this forum. 

Instead I will just make two statements:

 

a) 750W is from Heat Geek, based on 0.9m/s and DT5, both of which are quire reasonable.   Of course it may not be possible to get 0.9m/s if the pipework is too long or badly installed, but if it is then 750W is what you will move at DT5/0.9m/s.  

b) The thrust of my posts here, which I think I made abundantly clear, was that given the disruption and cost that re-piping causes., existing microbore should not necessarily be dismissed without doing the design,   Even it requires an extra water pump to achieve sufficient flow rate, the additional 35-50W consumption may pale into insignificance compared to the re-piping cost and disruption.  That should be a choice for the householder once a proper design has determined the options.

 

 

I will also ask two questions of you:

 

1. You said that "there is an ideal pipe diameter, go either side of it too much and the system loses efficiency."  Can you please explain the mechanism whereby an oversized pipe makes the system less efficient

2. From the tone of your responses I get the feel that you may believe that microbore can never work in a heat pump system.  Is that your belief and if so on what basis?

 

Finally, I am quite happy with my own system thank you.  The proof of the pudding is in the eating, and I certainly would not have wanted the unnecessary pipework replacements that some of the more gung-ho installers were suggesting unless they were absolutely essential, which evidently they were not.  It's my house so its my choice!

Not one bit of it is offensive.

1. Yes I could

2. No

Posted by: @jamespa

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It's my house so its my choice!

This childish response says it all.

I had hoped this was a place for facts and reasonable debate, it appears not. You make that quite clear and you're a moderator.

I came here to say this blanket statement:

Posted by: @jamespa

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You should be able to do 750W comfortably through 8mm id pipe without impacting efficiency so if no rad is  over this size no problem.  Even if they are you may well be able to get away with it with a bit of finessing of pumps/DT etc., or just replump one section.  Personally I detest throwing out perfectly good kit and a full replumb is pretty disruptive.

Is incorrect, which it is. I've backed up why it is.

You have a bee in your bonnet about re-pipes and it clouds your judgement. You can't compare your house to his, they're two very different jobs.

You don't seem to be able to answer my questions or produce any logical responses so there is no point in carrying on.

Bye bye.

I hesitate before responding, but there are points to be clarified for the benefit of the OP and other members.

Posted by: @deltona

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Not one bit of it is offensive.

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It's not for @deltona to dictate whether someone is allowed or not to find something offensive. This forum is all about collaboration and, if there are disagreements, debate that is not antagonistic or aggressive.

Posted by: @deltona

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1. Yes I could

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Could, but didn't. The assertion that oversized piping could materially reduce system efficiency still remains to be demonstrated, and so should be ignored until any objective evidence is provided.

Posted by: @deltona

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Posted by: @jamespa

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It's my house so its my choice!

This childish response says it all.

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There's nothing childish about reminding others not to dictate what you're supposed to do with your own property. There are plenty of members here in difficult situations because less than professional installers were trying to do precisely that kind of dictating, so never apologise for exercising your right to make your own choices - especially when in full knowledge of the compromises, as @jamespa was here. 

Posted by: @deltona

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You can't compare your house to his, they're two very different jobs.

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This is the most important detail. At no point has @jamespa's house been compared with @iotum's. Parallels have been drawn, certainly, but the message provided by @jamespa and @editor is that there are indeed credible alternatives to a highly disruptive full repipe. No-one's suggested a full repipe shouldn't be done but the valid question has been raised as to whether a repipe needs to be done along with the criteria that would influence that. That decision lies with @iotum as the now better informed homeowner - who is able to assimilate the different opinions and come to his own assessment - and that then brings us back to the paraphrased "his house, his choice". Nothing childish about it.

@deltona, I will remind you that @jamespa is not the only moderator here. Your use of antagonistic language - such as "unprofessional" and "childish" - and your aggressive approach are both potentially contravening the rules of the forum and as such further postings, if they overstep the mark, may well be removed by any one of us. Please play nice.

I’m going to step in here. Any further arguing, bickering or personal back-and-forth on this thread will be removed. No exceptions.

Renewable Heating Hub was set up deliberately as a polite, constructive space for homeowners, installers and industry professionals to discuss, debate and sometimes disagree. Disagreement is absolutely fine, encouraged, even, but it must be done respectfully.

What we will not tolerate is behaviour that is unnecessarily aggressive, dismissive, antagonistic or condescending. This platform is not Facebook or X, where that sort of conduct is often rewarded or encouraged. It doesn’t belong here.

You are free to challenge ideas, question assumptions and present alternative viewpoints. You are not free to belittle other members, dictate what they should or shouldn’t find offensive, or escalate discussions into personal confrontations.

Moderators have already shown a great deal of patience in this thread. Going forward, any comments that cross the line into disrespectful or belligerent territory will be deleted and further action may follow if necessary.

Let’s get back to what this forum exists for: sharing knowledge, helping homeowners make informed decisions and having robust discussions without losing basic courtesy and professionalism.

@iotum, let’s get the conversation back on track. Did you have any further queries about MLCP?

@editor nope. The info you reported was sufficient for me.  I now know the sort of questions to ask an installer about it.