Anti freeze valves/glycol in an air source heat pump, which is best ?

[@BrianSmith-nw2jo]

Once the vent has been activated does the vent close it self once it earms back up

[@giannnis12]

Hello from Greece, with propylene clycol antifreeze we have corrosion protection in the unit and they have better heat transfer

[@philiptyte6491]

Yes some contain corrosion inhibitors, but glycol reduces the specific heat capacity of the water therefore reducing heat transfer.

[@olalekanoyedokun4494]

Hello Derick, Do you have a video about a one- pipe system ?

[@tomkatgastraining]

Depends on what information you are after

[@Heatingandplumbing1]

cons to anti freeze can pass and thus pressure issues arise as they get older. Pro of anti freeze valves are higher scop. but need biocide and inhibitor.

[@nigelmoore6738]

I've checked the water in 2 different heat pump installs with my refractometer and didn't get a reading showing any frost protection, I could smell there was some type of glycol in it but did this mean there wasn't enough?

[@tomkatgastraining]

Correct 👍🏻

[@UrbanPlumbers]

good manufacturers do not require either. Viessmann and NIBE can be installed with none of this.

[@tomkatgastraining]

Very interested to know If the power goes off or the unit breaks down and it’s minus 10 degrees centigrade outside how do they stop the water from freezing in the unit because this hasn’t been mentioned in the training.

[@UrbanPlumbers]

@@tomkatgastrainingthere are other methods such as gravity circulation from a buffer installed in a cellar or battery back up that runs aux circulator. For UK conditions it is deemed that nothing is required by some manus. Also ,glycol should not be used with R290 heat pumps.

[@tomkatgastraining]

@@UrbanPlumbers what if you don’t have a cellar or you don’t have battery backup installed because one you have no room or 2 can’t afford it.

[@UrbanPlumbers]

@@tomkatgastrainingas I said before - nothing is required at all by NIBE and Viessmann. Also if you install and AFV and the heat exchanger splits, you have no warranty anyway.

[@tomkatgastraining]

@@UrbanPlumbers the more I find out about heat pumps in my training journey the more I think they are no competition to a gas boiler. Thanks for the input I really appreciate it.

[@Heatingandplumbing1]

glycol reduces scop not kw output in my opinion.

[@tomkatgastraining]

According to the manufacturers of heat pumps it reduces the output of the unit

[@pt6423]

Correct.

[@UrbanPlumbers]

it reduces both - SHC of water drops and system requires hihigherhger flow rate for the same output, thus reducing output and cop.

[@pt6423]

Fit anti-freeze valve and X700.

[@Brian-1948]

Propylene glycol is a safer non-toxic fluid.

[@otoole767]

Anti freeze valve

[@7dayplumbingservices195]

antifreeze valves , again depend of the MI