Good time to replace radiators?

[McKendrigo]

Hi,

I'm just wanting to get some advice as to whether it's advisable for me to have some/all of my radiators replaced.

I had a new combi boiler installed about a year ago, shortly after we moved in. During the install the system as given a chemical flush. I had an engineer give the boiler its first annual service last week, and he indicated that the water in the CH system was pretty dirty, especially considering it was a virtually new boiler.

He has recommended a power flush to purge the system of all that dirt. I'm not surprised at all the system needs a flush, the old boiler was 10-15 years old and I wouldn't be surprised if the CH never got a power flush during that time. I understand it's also advisable to keep the new boiler running smoothly.

What I'd like some advice on is whether its also advisable to replace the old radiators at the same time? By the look of them they are mostly 15+ years old. There's no obvious external problems with them (like leaks or rust), but what I'd like to avoid is paying for a power flush only to find out in a year or two that the radiators are so old the CH water is needing yet another power flush.

If it's probably fine to keep the radiators for now, then great, but I'm open to spending some money getting the radiators sorted now to save me money and hassle a bit down the road.

Thanks!

 

[motorbiking]

It's possible that the recommendation for a power flush is a "value added upsell". Its also possible that the original installer failed to add inhibitor to the system when he commissioned it.

I'd drain it back a bit and add some.

If the radiators aren't leaking and the house is warm, I would keep them.

 

[McKendrigo]

Given the age of the CH and previous boiler, and the fact that I don't think the previous owners were particularly good at maintaining stuff around the house, I'm inclined to believe that the recommendation for a power flush is genuine rather than the service engineer trying to "upsell".

I'm leaning towards a power flush for peace of mind and to ensure the boiler's 10 year warranty is safe. If the boiler got damaged by dirt and the warranty was null and void, a new boiler would cost a lot more than a power flush.

Edit: my gut feeling is that I also have to bleed the radiators more often that I ought to (certainly noticeably more regularly than my previous home), which I understand may be a symptom of CH with a buildup of sludge, so that's another thing making me lean towards a getting the flush done.

Generally the radiators seem fine, so I think I'll just keep them then. I had in my mind I'd be replacing them whenever the current boiler packs in, which hopefully won't be any time soon!

Thanks for your advice, much appreciated.

 

[Madrab]

If the system has flow and return drain points, which it should have, and the system is 15mm pipework then a drain and mains flush through each rad should be all it needs at a lot less cost than a power flush, with similar results. The system should ideally have a mag filter on the return close to the boiler so crud doesn't make it's way into the boiler.

If the water is as black as coal then take each rad off and hose flush it outside too.

 

[McKendrigo]

Thanks Madrab - I'd replied before I saw your reply too.

There is indeed a mag filter on the return, near the boiler. The engineer who serviced the boiler last week said the mag filter looked dirty when he checked it, which prompted his suggestion for a power flush.

 

[Lower]

If the mag filter is dirty then it's doing it's job.

 

[Harry Bloomfield]

I'm leaning towards a power flush for peace of mind and to ensure the boiler's 10 year warranty is safe. If the boiler got damaged by dirt and the warranty was null and void, a new boiler would cost a lot more than a power flush.

It would have been sensible for the whole system to have been completely drained, then depending on the colour of what came out, have simply given it a flush, or recommended a power flush. If the radiators all work and are adequate, not leaking, they are fine.

You could still drain, flush, refill and add inhibitor yourself easily enough, once the warmer weather appears.

 

[Madrab]

The engineer who serviced the boiler last week said the mag filter looked dirty

It's not about whether the mag filter looks dirty TBH, it's all about the system water and what colour that is. If the system water is clear or straw coloured then I'd question whether it needs power flushed. In fact a power flush can cause more problems that it solves by stirring everything up. That's why a mains flush may be better.

A lot of older systems, especially old rads can have some bit 'n' pieces floating around, old radiators are like that. As long as the filter is catching the dross then great.

 

[McKendrigo]

Hi everyone,

Thanks again for all your inputs.

I've decided that I'll just leave it for now. If it's relatively easy to drain, check the water, refill and add inhibitor as a DIY job, I'll give that a go when the warmer weather returns. If the water looks dodgy then, I can consider what to do.

I'll probably email the boiler manufacturer and/or check the warranty carefully, just to check if failing to have a power flush done could invalidate the warranty. Better to find that out in any case.

 

[Madrab]

I'll probably email the boiler manufacturer and/or check the warranty carefully, just to check if failing to have a power flush done could invalidate the warranty. Better to find that out in any case.

Careful what you 'tell' the manufacturer, if they identify you and there is an issue then they could invalidate things.

It's part of the installation requirements (benchmark) that the system should be flushed/cleaned to BS7593 and as per the MI

 

[Mottie]

I've decided that I'll just leave it for now. If it's relatively easy to drain, check the water, refill and add inhibitor as a DIY job, I'll give that a go when the warmer weather returns.

If you are handy with a spanner, you could remove each radiator in turn, take them outside, give them a good shake up and flush through with a hose. Keep shaking and flushing until water runs clear. Refil system, add some cleaner, run them for the recommended time, drain the system and refill a few times to get all cleaner out of them and do a final fill with some inhibitor.

 

[gas112]

do your rads all heat up ok and are they roughly same temp all over with no cold spots ?

 

[McKendrigo]

do your rads all heat up ok and are they roughly same temp all over with no cold spots ?

They all seem to heat up okay. I get the occasional cold spot from air trapped in the system, that needs bled out, but otherwise the don't seem to have any obvious cold spots.

 

[McKendrigo]

Careful what you 'tell' the manufacturer, if they identify you and there is an issue then they could invalidate things.

It's part of the installation requirements (benchmark) that the system should be flushed/cleaned to BS7593 and as per the MI

I did think of that, I was going to play dumb and pretend to be enquiring about a boiler I was going to install rather than discuss one I already had!

Regarding flushing/cleaning to BS7593 - the system was flushed out and given a chemical flush during install, and that is marked on the paperwork. That's enough to satisfy BS7593, if I understand correctly?

 

[gas112]

my thoughts on this from your answers is someone is trying to sell you something you do not need