New boiler or not?

[mp129]

Hello folks,

Long overdue update. Sorry for the delay. I went into information overload, with various engineers telling me different but equally plausible things.

Finally got the job done last week for half the price (3 way valve, replacement radiator and a smart thermostat). During the work it transpired that yet another recently installed radiator had been leaking

The guy who did the work said he couldn't understand why so many radiators had leaked, He did look genuinely baffled but said lack of inhibitor wouldn't explain it and his firm routinely uses this supplier of radiators without problems. From what people are saying on this thread I believe that to be nonsense, yet he works for an established local firm with a reputation to protect!

Thinking about it now, he drained the system but I don’t remember him going into the loft, so presumably there is now no inhibitor in the system! Can I just buy some and tip it into the tank myself?

Thanks for any advice.

 

[Wayners]

Yeah.
You can buy a inhibitor test kit to test the concentration.
From what I have been told you can't have too much inhibitor. Add some more to tank

 

[Harry Bloomfield]

Thinking about it now, he drained the system but I don’t remember him going into the loft, so presumably there is now no inhibitor in the system! Can I just buy some and tip it into the tank myself?

Inhibitor can be added at a radiator, but quicker/easier to simply add to the loft tank, before the water is turn back on to refill the system. If you have doubts, it's cheaper to simply buy a bottle of inhibitor, and add it, than to test with a kit. Having double the amount in, is not a problem.

 

[mp129]

Thanks both.

Can it be added to the tank even after the system has been refilled?

 

[Wayners]

Yeah. You can bleed a radiator to get some in .
Take a while to to get water through radiators but it can be done

 

[Harry Bloomfield]

Can it be added to the tank even after the system has been refilled?

Yes, it will take some time to mix in the system if you just pour it in the tank, but it will get there. Better though, if you can drop the level a bit first, before adding it, by bleeding water from a radiator, after turning the mains water off, or holding/tieing up the float arm. Even easier with some help, if the helper can do the bleeding, and you watch the level go down, to shout stop.

 

[drives]

We run our CH system without any inhibitor and use a spirovent to remove air bubbles. You may find this an interesting read about water quality and corrosion etc:

https://www.heatgeek.com/articles/articles-home?p=heating-water-treatment-explained-vdi-2035

 

[fixitflav]

We run our CH system without any inhibitor and use a spirovent to remove air bubbles. You may find this an interesting read about water quality and corrosion etc:

https://www.heatgeek.com/articles/articles-home?p=heating-water-treatment-explained-vdi-2035

Interesting if you have the patience to get through it! But I don't think I'll be giving up using inhibitor. I'm pretty sure my DO is low, but no idea about conductivity.
Edit - if you're getting much gas from the Spirovent that's most likely hydrogen, not a good sign. Does it burn?

 

[Harry Bloomfield]

We run our CH system without any inhibitor and use a spirovent to remove air bubbles. You may find this an interesting read about water quality and corrosion etc:

As a mere mortal, I will continue to put my faith in inhibitor. It has kept my system free of rust, blocked pipes and radiators, for 40 years.

 

[fixitflav]

Yeah.
You can buy a inhibitor test kit to test the concentration.
From what I have been told you can't have too much inhibitor. Add some more to tank

I bought one in 2010 (it wasn't cheap!) but found the colour chart vague. Don't know if later kits are any better but these days I do an annual bright wire nail test.

 

[fixitflav]

Can I just buy some and tip it into the tank myself?

Maybe a bit late now the job is done, but a Magnaclean or similar would be a good investment. Apart from its main job it's very useful for adding inhibitor, and sampling the system water for a bright wire nail test.

 

[drives]

Interesting if you have the patience to get through it! But I don't think I'll be giving up using inhibitor. I'm pretty sure my DO is low, but no idea about conductivity.
Edit - if you're getting much gas from the Spirovent that's most likely hydrogen, not a good sign. Does it burn?

No nothing really- it's just there to get rid of microbubbles so any gas from the vent is barely detectable, or certainly not now that it's been running for a few months since last drain and refill.

It seems to be working fine and our system water is very clean. I hardly get anything from our magnetic filter now when I clean it out.

 

[drives]

As a mere mortal, I will continue to put my faith in inhibitor. It has kept my system free of rust, blocked pipes and radiators, for 40 years.

Just a different school of thought I guess and perhaps neither is wrong, as long as there is a strategy to prevent corrosion. I'm not an expert either and hadn't really considered anything other than inhibitor until recently and having done some reading up on it.

 

[gas112]

i have fitted systems that were in for decades with no inhibitor and the water was crystal clear when eventually drained for new boilers.
Proper installation stops any fresh water/oxygen ingress

 

[mp129]

Thanks everyone.

Unfortunately the more I read the more confused I'm getting.

Fixitflav, Why would it be too late now the job has been done? I assume the inhibitor is always the last step in the job. What is a bright wire nail test?

Harry, why drop the water level before adding? Could I just scoop some water out of the tank? Would adding at a radiator be better? If so, how?

The water where we live is what one plumber described to me as "crap". (ie: it's very hard - limescale builds up in the basins and toilets). Is that a contributing factor?

I need to do something. I'm sick of replacing radiators. Maybe I'll just pay someone to drain the system again and watch him add inhibitor before refilling.