Draining System with Aladdin HC30 autobleeds

Hi folks - we're getting there with our heating system, but there's still 2 radiators blocked upstairs. The top 30-40% heat up, but the rest must be full of sludge. We got others working by taking off and hosing down outside - but they were smaller, downstairs, nearer doors and above tiled floors.

So - 3 options:

1. getting plumber to do power flush etc. downside: cost, it's old system and may leak?
2. taking off and cleaning manually. downside: weight and risk of getting sludge on carpets!
3. try chemicals -x400 first.

If we're going to try chemicals first - I'm just wondering if we'll need to drain and refill the system after the x400 has been in for a few weeks or if there are an options that doesn't require the full empty/refilling. It's a pressurised system, and the upstairs radiators all have those Aladdin HC30 automatic bleed vent things, so I can't just open the bleep taps to drain. I've never drained the whole system so no sure how easy/hard that is.

Or it even a possible to just put some x400 in the 2 individual sludged up radiators, leave it in for a bit, then drain into a bucket in situ?

Cheers

Just unscrew and remove the HV30 valves instead. If its the HV30C then use the tool that came with them to remove the insert instead. If it is the HV30 then remove the entire unit and get some silicone grease to put on the rubber washer before refitting.

jonshutt2 said:

Or it even a possible to just put some x400 in the 2 individual sludged up radiators, leave it in for a bit, then drain into a bucket in situ?

Click to expand...

No.

If you have a system filter such as a Magnaclean, it will trap quite a lot of the sediment loosened by the chemical, so you will have to keep emptying it until it stays clean, but this is not as good as cleaning, draining and rinsing.

If you think you have a sludge problem, it's a good idea to get a system filter fitted, on top of whatever else you do.

A chemical clean and drain, after 4 weeks, will only cost you £15 and a couple of hours of your time, so is always worth a try.

p.s.
when you remove a radiator from the wall, turn it upside down immediately. Then sludge and water will not run out as you carry it away.

gblades - thanks for the hv30 / hv30c advice.
johnD - thanks for the advice about draining and removing the radiator. I'll grab some chemicals and wait for the next rainy weekend... and give it a shot

Did I read somewhere that you can pour the x400 in through the magnaclean filter or do I need to buy a dosing kit (it's a pressurised system).