hot water cylinder lost 30 degrees over night

rosnacanee

Hi all,

Had visitors over yesterday and had our stove light all day. The temperature of the hot water cylinder was 60 degrees at 10.30pm last night, got up this morning and checked the cylinder again and it was down to between 25 and 30 degrees.

No body had a shower etc cannot understand such a heat loss.

My stove is a hunter 8, has a thermostat on the pipe at the back set at 55oC, the stat on the Joule 300L solar tank is set at 60oC. There is a pump to circulate the water and its gravity also if the pump fails. I dont have the solar panels installed yet so the water is heated either by the stove or the oil (which is timed to come on at various times during the day).

Could anyone offer any soutions to this problem?

I also notice that even if the stove isnt lit the top of it can be hot when the oil is heating the water.

I have underfloor heating downstairs and rads upstairs. Ill attach some pictures.

Thanks

rosnacanee

a few more pics

Outkast_IRE

a start would be to insulate all the pipework connected to the cylinder and see if that helps somewhat, insulate it with thick wall armaflex or something similar.

oikster

Your oil boiler should not heat your stove and vice versa. You are wasting heat from whichever appliance is on into the one that is off. Also why are you pumping the water from the stove to the cylinder? This is normally a gravity circuit not both.

oikster

IF THAT IS AN UNVENTED CYLINDER AND YOUR STOVE IS CONNECTED TO IT UNDER NO CIRCUMSTANCES SHOULD THIS BE USED.I MEAN UNDER NO CIRCUMSTANCES.

heinbloed

As said by previous posters: the entire system should be well insulated. Pipes and connections, junctions and cylinder.

Not only the thermal insulation is important but the avoidance of the thermosyphoning effect. The way the installation is done as seen on this picture

https://us.v-cdn.net/6034073/uploads/attachments/115314/199510.jpg

is wrong. Warm water travels upwards, cold water falls down. This way your thermal storage will empty itself very quickly.

The cylinder seems to be on the small side, bringing it up only to 60 degrees Celsius in the modus operandi as described in the op indicates a faulty plumbing or usage.

Would the original installer be able to help?

Beside the lack of insulation there might be some user advice necessary.

Oikster's comment is not correct, all boilers can feed a CH system, no matter what fuel or pressure is involved. Intelligence of the installer is always asked for.

oikster

Heinbloed I didn't set out to panic the user of this system. My sole intention was to STOP them from using it. The stove used in this installation is not suitable for pressurised systems. I dont care how many safety valves,pressure and temperature valves, motorised valves and thermostats are on this system, it is not a legal installation. In other parts of the EU maybe but not here.

heinbloed

Wrong, Oikster. All installations are legal as long as they are sound and save.

There is a boiler directive legally binding all Irish boiler installations since last year(boiler directive). As long as this is adhered to - no problem.

The OP provided us with a limited point of view, naturally, there might be heat exchangers involved in the system (not visible to us) separating the pressurised and non-pressurised parts.

oikster

Wrong Heinbloed SOLID FUEL APPLIANCE STRAIGHT TO UNVENTED CYLINDER. Safety was the last thing on the mind of this installer.

paddy147

heinbloed wrote: »

Wrong, Oikster. All installations are legal as long as they are sound and save.

There is a boiler directive legally binding all Irish boiler installations since last year(boiler directive). As long as this is adhered to - no problem.

The OP provided us with a limited point of view, naturally, there might be heat exchangers involved in the system (not visible to us) separating the pressurised and non-pressurised parts.

Could you throw your brain-power over to the other thread (outdoor tap) now please and post there too.

Thanks.

Range Tribune Twin Coil Unvented Cylinders
>Duplex stainless steel for ultimate peace of mind
>Fully transferable 25 year guarantee
>High flow-rate controls - ideal for multiple bathrooms & power showering
>Fast reheat and high insulation values resulting in high efficiency
>A Complete package - just add pipework

Range Twin Coil Tribune Hot Water Cylinders can be used in various ways:

1) To couple two different boilers up to the Tribune
2) For systems with solar heating. Solar heat is fed in via the lower coil.
3) To give very quick reheat times. Plumb both coils up in parallel. Reheat time will be approximately half but boiler power required double

IMPORTANT NOTICE

It is a requirement of building regulations that any such heat source connected to an Unvented cylinder (such as Tribune) be under full thermostatic control and are able to turn themselves COMPLETELY off

As a result you cannot connect an Aga or a solid fuel stove to a Tribune.

oikster

You mentioned thermosiphoning in one of your posts as a possible explanation to heat loss. Unvented cylinders are not provided with gravity compatible coils and tell me how does thermosiphoning occur through a heat exchanger. And you question my intelligence:rolleyes:

oikster

The only worrying thing is that the OP hasn't got back to us so we can explain the problem.

heinbloed

Oikster wrote:

Wrong Heinbloed SOLID FUEL APPLIANCE STRAIGHT TO UNVENTED CYLINDER

My question:

Where did Oikster read

SOLID FUEL APPLIANCE STRAIGHT TO UNVENTED CYLINDER

?

Maybe the enhanced part of Oikster's post is a quoting, maybe an interpretation ....

Thanks.

oikster

Mods feel free to ban me HEINBLOED YOU ARE AN IDIOT

oikster

oikster wrote: »

Mods feel free to ban me HEINBLOED YOU ARE AN IDIOT

Yep.

rosnacanee

Hi lads, thanks for all the help, not really sure what to do, suppose a call to the original plumber might be a start. Had another plumber in recently putting in bathroom suite and he thought everything was safe with the stove etc, bit worried now, is there any1 that could come in and evaluate the whole system

heinbloed

heinbloed wrote: »

Oikster wrote:



My question:

Where did Oikster read

?

Maybe the enhanced part of Oikster's post is a quoting, maybe an interpretation ....

Thanks.

It's always best to assume the worst;) you mention a heat exchanger, I have only seen two fitted and i'v seen a lot of installation, Oiksters warning would lead to the OP checking to confirm the type installation, your post on the other hand could lead to OP disregarding a perfectly valid warning.

rosnacanee

A quick explanation if its any use, as far as I'm aware, the rads are a seperate sealed pressurised system, the ufh is the same. The stove heats only the dhw it doesnt do anything for the rads or ufh, plumber said I would need a heat exchanger for that, and that it would our could be risky

rosnacanee

rosnacanee wrote: »

Hi lads, thanks for all the help, not really sure what to do, suppose a call to the original plumber might be a start. Had another plumber in recently putting in bathroom suite and he thought everything was safe with the stove etc, bit worried now, is there any1 that could come in and evaluate the whole system

The issue is that with a solid fuel stove fitted to a unvented cylinder you could have heat feeding your cylinder that is not thermostatically controlled which could "pertentunatly" lead to over heating/pressurising the cylinder which can be very dangerous(doesn't happen often, but is not pretty when it does).

Speaking as a cylinder manufactures technician I would never ok a heat sourse that can't be controlled by a off switch/ thermostat fitted on the heat source, irrespective of what valves or temperture controls on the cylinder, contact the your cylinder manufacture for further advice with there cylinder, Gary.

oikster

Gary,as far as I am concerned ,there is only one safe way to interconnect an unvented cylinder and a solid fuel appliance and that is through a vented buffer. I did not see one in any of the OPs photographs and I doubt if they would miss such a large piece of kit. But your advice to the OP is correct in that they should at least have the installation checked over.

rosnacanee

Perfect will give them a ring tuesday and c what they say. It is a triple coil cylinder by the way but you prob know that from pics. Thanks for your help, better to know the dangers before they happen

Paranoia is a beautiful thing when it comes to unvented cylinders

oikster

:eek::eek::eek::eek::eek::eek::eek::eek::D

JohnnieK

It could be as simple as the circulating pump running while there all fast asleep. The pipe stat might be faulty behind the stove.

JohnnieK

oikster wrote: »

Mods feel free to ban me HEINBLOED YOU ARE AN IDIOT

:D:D:D:D:pac::pac::pac::pac::pac::D:D:D:D

JohnnieK

rosnacanee wrote: »

Perfect will give them a ring tuesday and c what they say. It is a triple coil cylinder by the way but you prob know that from pics. Thanks for your help, better to know the dangers before they happen

The make of the cylinder is Jouel, There Irish so you could call them and ask there advise.

rosepaddy

rosnacanee wrote: »

Hi all,

Had visitors over yesterday and had our stove light all day. The temperature of the hot water cylinder was 60 degrees at 10.30pm last night, got up this morning and checked the cylinder again and it was down to between 25 and 30 degrees.

No body had a shower etc cannot understand such a heat loss.

My stove is a hunter 8, has a thermostat on the pipe at the back set at 55oC, the stat on the Joule 300L solar tank is set at 60oC. There is a pump to circulate the water and its gravity also if the pump fails. I dont have the solar panels installed yet so the water is heated either by the stove or the oil (which is timed to come on at various times during the day).

Could anyone offer any soutions to this problem?

I also notice that even if the stove isnt lit the top of it can be hot when the oil is heating the water.

I have underfloor heating downstairs and rads upstairs. Ill attach some pictures.

Thanks

it is possible that the positioning of the pipe work in you cylinder is leading to an automatic recycle of water through your pipe work this can easily lead to your tank being warm at night but when you turn off or it goes off the water will still continue to circulate resulting in you tank loosing temperature test this by turning on you boiler and feel yoy pipe leading to your solid fuel stove even though your stove might not be on you may find it is being warmed from the cylinder it is a fairly common problem. what temp is your underfloor coming on at is it a triple coil/dual coil

deandean

OP if this is of any help to you: I have an original copper cylinder, 'upgraded' with two lagging jackets. Like wearing two overcoats.

For the craic I instrumented it and overnight it loses 1DegC per hour. So, at 10pm water is at 65DegC, 7am next morning water temp is 54DegC.

Your sylinder should be far better insulated - you might be losing 0.5DegC per hour - so the temperature loss you are seeing has gotta be related to something sucking heat out of the cylinder.

Suggest you get up at 2am tomorrow morning and feel all the pipes around the cylinder, see which ones are hot, that'll guide you to the problem.