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Troubleshooting

the_lunatic_is_in_my_head
Posts: 9,504 Forumite



The flow and return from the heat pump to the cylinder has this valve on each pipe, part at the top has a little hole and there is a gargling sound as air is coming out but there is also a small puddle of water on the floor below.
Very grateful for any advice on what's happening here please.
Edited to add, I think it's a frost protection valve and I think the water is coming out of the little hole at the top.
In the game of chess you can never let your adversary see your pieces
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It is one of these TF1 Antifreeze Valve - Fernox UK may be worth reading the installation instructions etc.,.
Has it been especially cold overnight recently?
If/when it operates there will be more than a small puddle!!
I'd guess it may have developed a fault. Consult your installer-maintainer if no-one here has better advice / knowledge.1 -
Rodders53 said:It is one of these TF1 Antifreeze Valve - Fernox UK may be worth reading the installation instructions etc.,.
Has it been especially cold overnight recently?
If/when it operates there will be more than a small puddle!!
I'd guess it may have developed a fault. Consult your installer-maintainer if no-one here has better advice / knowledge.
Possibly completely unrelated but we were bleeding the rads yesterday (3 of them had a lot of air but we haven't bled them since it was installed last year).
I'm a bit confused about the set up but I think; we used to have a woodburning stove with a back boiler and the water that went through the stove went through a coil in the cylinder with that coil heating the hot water for baths, etc and then went round the rads.
I believe this system is the opposite in that the water that goes through the heat pump is the water in the cylinder which in turn heats up the coil for rads.
If that is correct the water that is leaking from this value is replaced by the mains and the air is the rads is completely unrelated?
Sorry just to edit again, the control panel says the outdoor temperature is 11 degrees and the value should be opening at temperatures of less than 3 and the water is trickling out wen the pump is running so it would appear the valve has possibly failed?In the game of chess you can never let your adversary see your pieces0 -
If that is correct the water that is leaking from this value is replaced by the mains and the air is the rads is completely unrelated?I can't speak for your setup but normally the water in the primary circuit of the heat pump would be the same water that's inside your radiators.Sorry just to edit again, the control panel says the outdoor temperature is 11 degrees and the value should be opening at temperatures of less than 3 and the water is trickling out wen the pump is running so it would appear the valve has possibly failed?
N. Hampshire, he/him. Octopus Intelligent Go elec & Tracker gas / Vodafone BB / iD mobile. Ripple Kirk Hill member.
2.72kWp PV facing SSW installed Jan 2012. 11 x 247w panels, 3.6kw inverter. 34 MWh generated, long-term average 2.6 Os.Not exactly back from my break, but dipping in and out of the forum.Ofgem cap table, Ofgem cap explainer. Economy 7 cap explainer. Gas vs E7 vs peak elec heating costs, Best kettle!1 -
QrizB said:I can't speak for your setup but normally the water in the primary circuit of the heat pump would be the same water that's inside your radiators.QrizB said:As I understand it, if the antifreeze valve opens as intended it'll dump the entire contents of your primary circuit. If it's dripping/trickling, it sounds more like a leak.In the game of chess you can never let your adversary see your pieces0
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IF the water gets down to 3 C that valve will open and dump all the water from the system... It is to prevent freezing damage. Water will (should) not be replenished automatically. More inhibitor may need adding if a substantial volume has been lost (and air bled out).
Check the HP pressure gauge to check if it is low.
NB it may be 11 now but lower overnight?
Here my weather station says 18 C outside now and 11 C was minimum overnight.
That valve has signs of historical if not current weeping leaks to my eyes (but a plumber on site would be more certain).
Sone HPs have a 'buffer tank' store for the circulating water in the house others don't. Your installers would know and in an ideal world would explain and leave manuals and design data... few do.1 -
QrizB said:I can't speak for your setup but normally the water in the primary circuit of the heat pump would be the same water that's inside your radiators.As above, no it shouldn't be automatically topped up. There might be a filling loop, a bit like a combi boiler?the_lunatic_is_in_my_head said:QrizB said:As I understand it, if the antifreeze valve opens as intended it'll dump the entire contents of your primary circuit. If it's dripping/trickling, it sounds more like a leak.N. Hampshire, he/him. Octopus Intelligent Go elec & Tracker gas / Vodafone BB / iD mobile. Ripple Kirk Hill member.
2.72kWp PV facing SSW installed Jan 2012. 11 x 247w panels, 3.6kw inverter. 34 MWh generated, long-term average 2.6 Os.Not exactly back from my break, but dipping in and out of the forum.Ofgem cap table, Ofgem cap explainer. Economy 7 cap explainer. Gas vs E7 vs peak elec heating costs, Best kettle!1 -
Rodders53 said:IF the water gets down to 3 C that valve will open and dump all the water from the system... It is to prevent freezing damage. Water will (should) not be replenished automatically. More inhibitor may need adding if a substantial volume has been lost (and air bled out).
Check the HP pressure gauge to check if it is low.
NB it may be 11 now but lower overnight?
Here my weather station says 18 C outside now and 11 C was minimum overnight.
That valve has signs of historical if not current weeping leaks to my eyes (but a plumber on site would be more certain).
Sone HPs have a 'buffer tank' store for the circulating water in the house others don't. Your installers would know and in an ideal world would explain and leave manuals and design data... few do.
Some Googling suggests the valve should dump the water out the bottom and the bit on the top (where the water is coming out) is called a vacuum breaker (don't understand what that does).
If the water doesn't fill up automatically is it a manual thing to add the water or a on/off valve somewhere?
Typical to occur on a weekend as everything is closed but will call the installers on Monday.
I don't think we have the buffer tank (there is just 2 expansion tanks). This is the pressure gauge under the expansion tank that feeds off the flow and return between the cylinder and heat pump:
There's a second gauge on the pipework around the cylinder:
I'm guessing that is low?In the game of chess you can never let your adversary see your pieces0 -
QrizB said:The heat pump should have a pressure switch (or flow switch?) so it won't run if the primary circuit is empty.QrizB said:As above, no it shouldn't be automatically topped up. There might be a filling loop, a bit like a combi boiler?
The vacuum breaker seems to open when there isn't enough pressure in the system so it's possible bleeding the rads but not using filling loop after has caused the vacuum breaker to do what it is supposed to do.
I'll wait a while to ensure the water in the system has cooled, bleed the rads one more time and get the pressure up to 1.5 bar and (fingers crossed!) see if water stops coming out of that vacuum breaker.
Thank you both for taking the time to reply, very much appreciatedIn the game of chess you can never let your adversary see your pieces1 -
The vacuum breaker is there to allow air into the system when the valve opens otherwise it would not be able to dump all the water.
Your pressure gauges are indicating that the pressure is less than 1 bar - normally the system would be pressurised to around 1 to 1.5 bar, so you've definitely got a loss of pressure caused by water leaking.
As others have said, the water in the heating circuit and hot water tank coil will be separate to the stuff you drink and wash with. There should not be anything that allows the system to automatically top-up the system.
That is usually achieved manually with a filling loop connected between the incoming mains and the heating circuit with a manual non-return valve and a flexible pipe (which generally should be left disconnected to avoid contaminating the mains water
As @QrizB says there will be a flow switch that will stop the heatpump if the flow is restricted, either by lots of TRVs closing or insufficient water in the system or if the pressure drops below a safe levelNever under estimate the power of stupid people in large numbers0
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