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(1) What would the expected pH be for a central heating system estimated to contain less than 2000 litres of water that was yesterday dosed with 50 litres of Trade-Chem C100+ inhibitor?

(2) The pH for the system water is 6.0 compared to the incoming mains water pH of 6.7. Is that expected or acceptable?

(3) And what would be a safe pH range for the water in such a system?

(4) Is there any method other than pH testing to determine the concentration of Trade-Chem C100+ inhibitor in a system?

This is another chapter in a long running saga regarding my ETA biomass boiler. The previous threads were ...

"Pressure drops when 650 litre buffer tank is filled with water but no drop with air"

"Wear And Tear Causing Leaks?"

"Jet Range by Wolseley - DN20 Isolation Valve"
 
What’s the materials in your system eg steel, copper, aluminium etc
 
What’s the materials in your system eg steel, copper, aluminium etc

Steel (presumably) - ETA Hack 70 boiler, ETA 650 litre buffer tank, ETA expansion vessel, Fernox TF1 Tees.

Copper - pipes.

Aluminium - not known but possibly within heat exchangers?

Plastic - Upanor underground insulated pipes, Fernox TF1 filters.
 
This should help

70FB6F53-9881-4816-90EE-51023D0CF3CC.jpeg
 
Ph of 9-10 ish

Atm you could be causing harm to your steel side
 
inbh is around 7.0
 
Trevor,

You really need to achieve a PH of 7. If you are not achieving that with the correct dilution - there is a contaminant in your system. If the system is a recent instal, the contaminant may be residual citric acid from a system cleaner. Generally tap water is PH neutral or slightly alkaline unless it has been drawn from peat bogs, or other acidic strata.

PH scale is logarithmic so a PH of 6 is 10 times more acidic than that of PH7

To neutralise tap water, fill the system with water that has passed through a neutralising filter ( about £60)
 
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Yesterday the system was power flushed with Trade-Chem C600 cleaner, following visible rust in the water and a pH of 4.65. Then refilled and 50 litres of Trade-Chem C100+ added.
 
Sentinel's suggestion is that if the cleanser hasn't been removed then it's a question of the system not being flushed properly (and inhibitor doesn't really work properly if the system contains dissolved metals so you may as well...) but that if your supply water is not neutral enough then it is usually easiest to 'simply' ship in water from elsewhere. Which is obviously easier in a domestic system when you only have a couple of hundred litres at most.

In your case, Shaun's suggestion of adding something alkaline sounds more feasible.
 
My only concern would be that this could make the water harder? But I suppose that is exactly what happens when acidic rain runs through a chalky rock and becomes neutralised so it's probably the same thing. Good shout, I reckon.

Ideally you'd probably use distilled water, but that might prove expensive...
 
My only concern would be that this could make the water harder? But I suppose that is exactly what happens when acidic rain runs through a chalky rock and becomes neutralised so it's probably the same thing. Good shout, I reckon.

Ideally you'd probably use distilled water, but that might prove expensive...

true but then your still to high for a steel buffer / boiler around 8-9 would be the middle

h1015v1_117_2.jpg
 
VDI 2035 (sheet 2) is the German standard for water in heating systems, you may have seen this quoted be manufacturers. I believe that we should be following this now, no longer can heating systems just be filled from the mains & if lucky some inhibitor added.

From what you have told us Trevor your system should have a PH of between 8.2 - 10 so you will need to raise it, swimming pool & hot tub suppliers have products which can be added to raise it.
The attached doc is very good & explains the whole of VDI 2035 & it is shown on Shaun's post attachment.
Water Treatment - Vietec HEATING
 
That’s a really interesting read.

Has anyone here ever filled a system with anything other than the mains water available at the property? (With the addition of inhibitor)
 
That’s a really interesting read.
Has anyone here ever filled a system with anything other than the mains water available at the property? (With the addition of inhibitor)
I know Andrew Millward does he got a cheap de-ionisation filter off internet & runs filling mains through it.
I don't do enough to warrant that but for £1.80 for 5Litres at Tesco I was thinking of refilling my mates system after all it would be cheaper than inhibitor.
It seems to be all all about getting the air out quickly (fitted an air separator) & getting the PH right.
 
Does anyone have access to the data sheets for Trade-Chem C100+ (C100S) inhibitor and Trade-Chem C600 power flush please? Also Trade-Chem step by step instructions on how to use the C600 power flush? I have been refused.
 
Yes, point blank refused. Apparently the Trade-Chem policy is to only supply such information to their existing customers. Why the secrecy?
 
Then if I were you I’d buy another cleaner??
 
Unfortunately I am constrained by the choice of chemicals already made by the supplier/installer of my biomass heating system. I am suspecting that the power flush conducted this week may not have been done properly, so I want to research both the power flush and inhibitor as thoroughly as possible.

Does anyone in here have a Trade-Chem account?
 
I think you’re doing too much here if you suspect it’s wrong I’d be getting the company back
 
I must have missed this one. Of course the chemical condition of ch water is important. As always the system must be tested watertight first...otherwise you will waste expensive chemicals, then drained...examine the drained water I do, then do,it again until clear. Run the whole thing up,to maximum and see what happens, drain. Then put in your preferred inhibitor as specified by the boiler manufacturer..as this is the most expensive component, use the test paper to indicate correct...photograph it...the metadata on your phone will date it anyway. Job done. I have worked with Sentinel etc often ...its good stuff but its universal and you must satisfy the boiler manu that its been done correct or your engineer nobody else. By the way Screwfix sell the same stuff under a different name way cheaper. Thats my take on this
Rob Foster aka centralheatking
 
Informative thread.

I've always wondered about the presence of cleaner in the system, from what I understand I could test this with simple litmus paper? So if cleaner was present in the system the ph would read acidic? And likewise the presence of inhibitor should read alkaline?

This would make testing for inhibitor so much easier, instead of having a manufacturer specific tester... or lack of and just doing it by eye, I can simply test some drain water with litmus paper! Very interesting
 
Well, I have a situation this week that 50 litres of C100+ inhibitor added to fresh mains water of 6.7pH, tests at 6.0pH.

To me that suggests that the system may not have been completely flushed clean after using C600 power flush? Prior to the power flush the water was visibily brown rusty with a pH of 4.3.
 
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