Heating System Antifreeze

[Old Son]

What product do you use in your heating systems. I have Sentinel at the moment but don't know how long it is supposed to last so was thinking of changing it very soon. I have been recommended Freezbreaker LT. Does anybody use this and what do they think please?

[NMEA]

We use Flomasta inhibited central heating antifreeze from Screwfix in all new installs at 25% concentration, it is economical and the Flomasta inhibitor is compatible so you can top up to maintain the anti corrosion properties and extend the drain down and refill intervals.

[Old Son]

Thanks NMEA, the Flomasta protects down to -11. Presumably you are comfortable that this will prevent freezing? I am thinking of the heater unit itself which is fitted below the cruiser stern where there are open vents either side of the engine bay. I do have valves either side of the heater unit and am wondering if I should remove the heater over winter if the boat is not being used or is this overkill?

[NMEA]

All our installs are down south so -11 is fine for us, you could increase the concentration to say 33% for more protection but not too much as it then affects the efficiency of heat transfer, not usually a real issue as the rads on many installs are well below the hearer capability anyway. I see little point in removing the heater unit for the winter really, other than you could use the opportunity to clean it out.

[Old Son]

Thanks very much for your advice. I will go the Flomasta route.

[David Schweizer]

I used a 40% mix of Bluecol/Halfords/Car Plan, etc.  Blue Antifreeze, and topped up the corrosion inhibitor every few years with some green stuff (cannot remember the name!)

[Old Son]

Thanks David.

Would it be worth running the heating a couple of times for an hour or so with some cleaner in it before I drain or drain as it is?

I am a leisure boater and have used the C/H about 20 times in the past 5 years.

 

[blackrose]

I used the same red 5 year antifreeze in my backboiler heating system as in my engine. Since it probably has better the antifreeze properties than central heating inhibitor I didn't see the point of using inhibitor, but does inhibitor do something else like reduce noise or something? The only disadvantage of engine antifreeze seems to be that the c/h header tank tends to get a bit smelly when it's hot - or that could be the short length of warm rubber car heater hose that's connecting the header tank that emits the smell, I'm not sure.

[David Schweizer]

7 minutes ago, blackrose said:

I used the same red 5 year antifreeze in my backboiler heating system as in my engine. Since it probably has better the antifreeze properties than central heating inhibitor I didn't see the point of using inhibitor, but does inhibitor do something else like reduce noise or something? The only disadvantage of engine antifreeze seems to be that the c/h header tank tends to get a bit smelly when it's hot - or that could be the short length of warm rubber car heater hose that's connecting the header tank that emits the smell, I'm not sure.

As I understand it Antifreeze Inhibitor helps to inhibit rust forming in the system. The downside with vehicle antifreeze is that whilst it retains its primary purpose of preventing the coolant from freezing, the inhibitor degrades over a period of three or four years and requires replenishing. This is easlily achieved these days with the addition of an inhibitor, typically less than a litre.

[NMEA]

I think people get a little confused about what antifreeze is, briefly antifreeze is a mixture of Glycol and additives which include inhibitor, the inhibitor adds nothing to frost protection but is essential to help prevent internal corrosion of the system parts including boiler and radiators. Glycol maintains its frost protection for some considerable time, but inhibitors become less effective and therefore many people change their antifreeze at regular intervals which is a way of replenishing the corrosion protection but does mean you are throwing away perfectly good glycol which is also quite toxic to the environment. The great thing about using an antifreeze like the Flomasta one, or indeed any other that you can source a compatible inhibitor for is you keep the glycol content and top up the corrosion inhibitor, cheaper and better for the environment.

[David Schweizer]

46 minutes ago, NMEA said:

I think people get a little confused about what antifreeze is, briefly antifreeze is a mixture of Glycol and additives which include inhibitor, the inhibitor adds nothing to frost protection but is essential to help prevent internal corrosion of the system parts including boiler and radiators. Glycol maintains its frost protection for some considerable time, but inhibitors become less effective and therefore many people change their antifreeze at regular intervals which is a way of replenishing the corrosion protection but does mean you are throwing away perfectly good glycol which is also quite toxic to the environment. The great thing about using an antifreeze like the Flomasta one, or indeed any other that you can source a compatible inhibitor for is you keep the glycol content and top up the corrosion inhibitor, cheaper and better for the environment.

????  I will go and find an egg to suck

51 minutes ago, David Schweizer said:

As I understand it Antifreeze Inhibitor helps to inhibit rust forming in the system. The downside with vehicle antifreeze is that whilst it retains its primary purpose of preventing the coolant from freezing, the inhibitor degrades over a period of three or four years and requires replenishing. This is easlily achieved these days with the addition of an inhibitor, typically less than a litre.

Edited March 3, 2018 by David Schweizer

[blackrose]

56 minutes ago, NMEA said:

I think people get a little confused about what antifreeze is, briefly antifreeze is a mixture of Glycol and additives which include inhibitor, the inhibitor adds nothing to frost protection but is essential to help prevent internal corrosion of the system parts including boiler and radiators. Glycol maintains its frost protection for some considerable time, but inhibitors become less effective and therefore many people change their antifreeze at regular intervals which is a way of replenishing the corrosion protection but does mean you are throwing away perfectly good glycol which is also quite toxic to the environment. The great thing about using an antifreeze like the Flomasta one, or indeed any other that you can source a compatible inhibitor for is you keep the glycol content and top up the corrosion inhibitor, cheaper and better for the environment.

I wasn't confused. I was told that the corrosion protection in my 5 year antifreeze would last as long as the corrosion protection in a c/h inhibitor, that's all. So how long does the corrosion protection last in a c/h inhibitor? 

[WotEver]

40 minutes ago, blackrose said:

I wasn't confused. I was told that the corrosion protection in my 5 year antifreeze would last as long as the corrosion protection in a c/h inhibitor, that's all. So how long does the corrosion protection last in a c/h inhibitor? 

I don’t think that’s the point being made. If you use a c/h product such as flomaster then when the corrosion protection requires enhancing you just add some more corrosion inhibitor to the system. You don’t need to drain down the system, simply add a bit more inhibitor. By contrast, vehicle antifreeze may well be incompatible with a standalone inhibitor (note all the warnings about mixing pink and blue) so you’d have to drain the entire system (and dispose of glycol) simply to enhance the corrosion protection. 

[blackrose]

Ok, I wasn't using any c/h product. I'd already drained down the c/h system before filling with red antifreeze.

[Tony Brooks]

I understand that the rate the corrosion inhibitors are used up, be it in automotive antifreeze or   central heating stuff is dependant upon how much corrosion they are inhibiting so if you have lots of light alloy and iron/steel in the system it may well be exhausted long before the same stuff in an all plastic system (I know there is no such thing).

I would lay odds that the "life" of antifreeze is well understated so the manufacturer has a good safety margin and ditto central heating inhibitor.

[bizzard]

It helps an awful lot if you don't use tap water in the heating system or in vehicle cooling systems. Rain water, distilled or even clean river water is much better.

[David Schweizer]

12 minutes ago, Tony Brooks said:

I understand that the rate the corrosion inhibitors are used up, be it in automotive antifreeze or   central heating stuff is dependant upon how much corrosion they are inhibiting so if you have lots of light alloy and iron/steel in the system it may well be exhausted long before the same stuff in an all plastic system (I know there is no such thing).

I would lay odds that the "life" of antifreeze is well understated so the manufacturer has a good safety margin and ditto central heating inhibitor.

I suspect you are correct. I used to test the Antifreeze properties in my coolant every year, and it was still providung the sme level of protection after more than ten years, but there was no way (that I knew of) to check the corrosionn inhibitor, so I added some which I bought from a specialist motor factor> From recollection it was compatible with both red and blue antifreeze, but was actually a luminous green colour.

[Up-Side-Down]

19 hours ago, David Schweizer said:

I suspect you are correct. I used to test the Antifreeze properties in my coolant every year, and it was still providung the sme level of protection after more than ten years, but there was no way (that I knew of) to check the corrosionn inhibitor, so I added some which I bought from a specialist motor factor> From recollection it was compatible with both red and blue antifreeze, but was actually a luminous green colour.

This was probably Morris's Ankorsol which describes itself as "A Fully Synthetic Corrosion Inhibitor for All Water Based Cooling and Heating Systems" and can be purchased from the Morris's Oils website – (01743 232200; www.morrislubricants.co.uk). It's sold in 1 litre bottles and mixed at a 2% concentration. As my skin tank is difficult to drain fully I add it to my engine coolant rather than replace the whole lot every four years or so. The whole lot should be replaced as per engine manufacturer's instructions which is usually listed in terms of hours of engine running.

[David Schweizer]

56 minutes ago, Up-Side-Down said:

This was probably Morris's Ankorsol which describes itself as "A Fully Synthetic Corrosion Inhibitor for All Water Based Cooling and Heating Systems" and can be purchased from the Morris's Oils website – (01743 232200; www.morrislubricants.co.uk). It's sold in 1 litre bottles and mixed at a 2% concentration. As my skin tank is difficult to drain fully I add it to my engine coolant rather than replace the whole lot every four years or so. The whole lot should be replaced as per engine manufacturer's instructions which is usually listed in terms of hours of engine running.

Yes, that's the stuff, I got it from Classic Oils when they were still in Aylesbury.  As on your on boat, our skin tank was difficult to drain so I drew about a litre of coolant from the Bowman an added the Ankersol via the filler neck. The Ankersol is quite thick so I added it gradually whilst the engine was running.