New combi boiler fitted - not flushed, no inhibitor added

[3phemeral]

We had a new Worcester Bosch combi boiler fitted several weeks ago to replace the (20+ year) old boiler. To my knowledge, the existing system (pipes/radiators - all in place already and likely as old or older than previous boiler) weren’t flushed. I asked about flushing during installation but the gas engineer said he doesn’t do power flush or MagnaCleanse himself and that as there’s no drain off valve and the property is a flat (all radiators at same level) he couldn’t empty the system for a chemical flush. He also says that as he fitted a MagnaClean Pro 2 filter there shouldn’t be any issues. To my knowledge, no inhibitor was added to the system either.

We’ve used the boiler since and haven’t noticed any issues: the water heats well and all radiators heat evenly across (at least to the touch). In case it's relevant, we’re in a soft water area, with no limescale buildup anywhere at any point.

I want to ensure the boiler lasts as long as possible and works efficiently.

What do you recommend at this point? How can I know if sludge is an issue (i.e. system not working as well as it should)? What issues could arise from no flush having taken place longer-term?

Thanks in advance!

 

[oldbuffer]

1. His excuses sound like rubbish. Any system can be drained and refilled - how did the water get into it in the first place?
2. Check the installation manual for your boiler, which he should have left with you after completing and signing the checklist at the back. If Worcester insist on a flush (which need not necessarily be a power flush) then your guarantee will not be valid without it.
3. Inhibitor should have been added. Its easy enough to do via the Magnaclean.
4. Fernox sell a water testing service. You could take a small sample from the system and have it tested. The test is not free. I don't know how much it costs.

 

[3phemeral]

Thanks for your prompt reply @oldbuffer.

1. I get your point about being able to fill the system: given there's no drain off valve, how should he have chemically cleaned the system?

2. He filled out Sentinel in the paperwork - but I don't believe any was added...

3. Do you recommend adding inhibitor at this point (after installation)? Or should a chemical flush be done first? I would need to get a drain off valve fitted to be able to drain the system tho.

4. Interesting - I had a look at this. It looks like it only tests whether Fernox-branded cleaner/inhibitor has been added. Are there other ways to determine the state/effectiveness of the rest of the system?

Thanks in advance!

 

[oldbuffer]

1. System can be drained via a radiator valve. More fiddly than if drain off fitted but plumbing 101.
2. Who knows.
3. The system should have inhibitor in it. If you are going to do a chemical flush it would be sensible to do that first. As mentioned above it can be done without a drain off valve, but easier with one.
4. Look at the Adey one. Its supposed to give you a measure of turbidity, which is sort of equivalent to a Total Dissolved Solids (TDS) measurement. If you fill a tall glass vessel (e.g. tall arrow flower vase) with water from the system, then let it settle, put it on a sheet of white paper and view downwards, then if you can see pretty much clear through, the system is clean.

You have a Magnaclean fitted. Check that on a weekly basis for a while. If it stays clean after a few checks, the system is probably clean enough.

 

[dilalio]

Part L Guide to BS 7593:2019 - Plumbing And Heating Magazine

The new British standard BS 7593:2019 is a code of practice for the preparation, commissioning and maintenance of domestic central heating and cooling water systems. It applies to individual domestic premises when commissioning a system for the first time on a new build, or re-commissioning...

plumbingmag.com

 

[drives]

You can buy Fernox express test kits which you can do at home, taking a small sample from a radiator/magnetic filter. I've ordered some as we have a similar scenario to you (want to check following system drain and refill and don't trust workmanship). The full kit containing 50 test strips is around £30 but you can buy a few test strips on ebay for much less.

inhibitor test strips