Flushing Out Radiators

[ouibonjour]

Do any experts think I should have my radiators flushed before installing an updated system (oil to gas) They are 1950s big old iron ones and the cost would be 1000 euros. Thanks

[davebro]

seems expensive!

[TonyV]

depends how many you have and how much sludge they have in them but £850 seems expensive.

[bookbinder]

I'm no expert, but I think that your radiators should be flushed. Better to start with a clean slate. If there are any problems later on, at least you'll know that they aren't caused by sludge in the system.

[jakep]

I am not an expert. We replaced the boiler after we moved into this house, probably about 15yrs ago, we did not flush system. Never completely happy with performance, despite bleeding rads and adding gunk and draining and refilling a couple of times.
In October last year we had a new boiler and a system flush. It is like a whole new ball game and the house is now properly warm, so worth it for us.
We have a three bed house with usual rads and it cost about £100.

[TonyV]

forgot to add if system is not flushed properly any sediment left in your system will lead to early failure of your new boiler, but installation guys should be able to sort it out for you.

[TheDevil]

It would be beneficial if your system was flushed but no one will be able to tell you how beneficial it would be, so it is hard to say if €1000 is worth it.

If you can afford it, then I would recommend it.

[Hardatit42]

Merely by filling and emptying you are flushing your system but I would fit a hydroponic filter to the system costing say £80 -120, but not inc. fitting and you could check every so often. This is well worth it, although you do not say size of system!

[TonyV]

have a look here for what cleaning chemicals cost
https://www.screwfix.com/c/heating-plumbing/cleaner/cat831462?cm_sp=managedredirect-_-plumbing-_-chcleaner

[The Builder]

If you're just changing the boiler, then flushing isn't necessary. Probably just draining down, and re-filling, plus rust inhibitor.

The real question is how long is it since the system was installed?
If in any doubt, then a flush is a good idea.
Are there a lot of rads? An average house should cost maybe a little over half that price.

You mention Euros. Is it in France?

[davebro]

Maybe it's a chateau?

[Ryzen]

Check out the water when its being drained...if its a very light colour then you should be ok..if it looks like ditch water then get it flushed and treated.Many boiler warranties will be challenged if proof of debris can be proven.

[ouibonjour]

Many thanks for all your helpful answers. To " The Builder" we have a big old house and there are 18 radiators in all. To Flush the rads and add thermostats on each of them, A complicated control box that neither of us would understand. Same boiler. Arrrange with the gas installation as we have none (it runs right past the door) Thats it - 8,500 Euros! We thought it was expensive. We live in France. And you can never know if someone it trying it on with the estimate.We live in France.

[The Builder]

Ah yes, I was concerned that the local "tradesmen" might be taking advantage, but I don't think that is the case now.

Average house, maybe nine radiators, power flushing should cost around €400-500, so your quotation looks about right.

Bonne chance ;o)

[ouibonjour]

Merci "M. Constructeur"