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By Homeowner
Hi there.

I have underfloor heating throughout my house and it seems to be working great. It's been in the house from new, 19 years ago and hasn't caused us any issues in that time.

Our plumber replaced a faulty circulation pump a few months ago and said that when he got it back to his workshop he found that it was filled with a dirty substance. He suggested that we get the underfloor heating flushed.

Soon after I switched on our boiler after being off for the Summer and we found that it was sounding noisy and whilst it heated fine it didn't sound as quiet and smooth as before the Summer. I mentioned this to our plumber and he said he'd quote for a new boiler (it's 7 years old - he fitted the last one). Since then it has been quiet and back to normal!

The plumber said that it could be the dirt he found in the pump making its way around the system that caused the noisy boiler and that it has just moved on. It's worth noting that he's not an underfloor heating specialist.

My question is do I need to flush the underfloor heating at the moment if it's working fine or should this be done periodically anyway?

I'm uncertain so thought I'd turn to you guys here for your advice.

User avatar
your ststem has liquidised magnetite flowwing around it. turned off in summer this all settles and solidifies into lumps only to be pushed around when heating is back on causing such problems.
if your boiler has not got a mag filter on it then the problem will get worse.

yes it needs a chemical treatment and wrinse out with the addition of a filter, i dont see any call for new boiler unless- its a rubish cheap brand or the internals are blocked!

false ecconomy if not attended to as it will cause more damage just when you dont want it and not that expensive or di it yourself.

ps- underfloor heating is just a big rad with a lot of valves to block up. :D
User avatar
Homeowner wrote:
November 29th, 2019, 5:39 pm
Ah that makes sense. So the So a flush would be sensible. I have a price for flushing that seems pretty high in the £750 mark or does that seem okay for both upstairs and down? Cheers
No! that sounds like british gas prices!
depends where you live also.
chemical flush is diy-able or £150-250 + £125 for a filter around here.
if you know how to drain and re-fill your systen its as hard as that- almost
User avatar
Homeowner wrote:
November 30th, 2019, 5:23 pm
Wow, that's quite a difference. I'm not overly knowledgable on plumbing and heating but that's very useful to know that our price is pretty rich! I certainly don't mind paying for a service but not if someone is trying to take liberties. Thanks for the info on that.
Bare in mind, thats a chem flush not powerflush and again- depends where you live as each parts of the country charge diffrent rates of labour as too the size of the company they are running.

YUP! :lol: :lol: :lol:

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