Heating fail. Help?

[Welderpaul]

Brrr. We have an air source heat system. We've lost the ground floor underfloor heating, but still have hot water and upstairs rads working as normal.

Any plumber within 1000 mile radius is busy and i'm struggling to find someone who can help. I'm told that the problem may lie with the 3 port valve and is more a plumbing issue than a renewable enery engineer problem.

Can anyone shed any light on what needs whacking to make it warm again?

Here's the gubbins.

Appreciated.

 

[hotponyshoes]

Funnily enough I have just come home to the same thing!
We, not quite as posh as I don't have underfloor heating.
Or air source.
Or, even a second storey on my house come to think of it....

But, I do a problem. The radiators and the hot water tank are both getting hot with only the heating turned on and that's not really getting that hot.
My problem is the 3 way valve.
Just look for a box connected at the junction of 3 pipes. It will also have a bit of cable going into it. (Mine is standard white mains flex)
It might have something printed on the cover if you are not sure? Even if it's only got a part number you could put that into Google and see what it is.

I just took the black cover off and you can see the valve and motor gubbins inside sonits pretty obvious once the cover is off.
Anyway. Find that and hit it. Seems to have sorted mine.

 

[knighty]

the actuator valves (you said 3 post, I can only see some 2 port ones in photos unless I'm missing it) - they have a little metal tab sticking out the side so you can manually open them, try that first - tab/stick thing slides along then locks in place to keep it open

feel which pipes are warm edit onto photos with lables for what does what etc. :-)

 

[brightspark]

slide the lever over on the tin 2 port valve and it latches on at the end . if it starts getting hot through the pipe it will be the little motor inside knacked . can get them from screwfix about 12 quid and easy to fit a new one if it moves over on its own powered up its not the motor or that valve

 

[Kayos]

Can't see any 3 port valves and the pump in the second picture is for the secondary hot water return

 

[brightspark]

if that is the valve for your heating test the wires to it back at the joint box brown and blue to see if its powered up with all controlls on its 240v heres the diagram of the motor inside https://www.google.co.uk/search?q=2+port+valve+wiring+colours&sxsrf=AOaemvLcV9vPCgcRI4JqBiY-2iRXNZt18Q:1639597875893&tbm=isch&source=iu&ictx=1&fir=nI4o-giDbPrRDM%2CPF4uYCMkV9ZnzM%2C_%3ByOUYIdo04pfpZM%2CPF4uYCMkV9ZnzM%2C_%3BrjOEDmaxns_TQM%2C0TtYRIt7-db60M%2C_%3BYHQPmLC7redzsM%2CJOKrke8iiHvpKM%2C_%3BqadBmPTA6PX1CM%2CCzoNM5m4029N3M%2C_%3BTRX1SFujejaYyM%2Cf69EsN4zZWOBTM%2C_%3BP-5ttNau-H19iM%2Cvrv_krt0fB2HQM%2C_%3BZ-491OP9iLgwfM%2CrnDAfkDubZZCdM%2C_%3BokzVYMRG0aRjzM%2C1sYmN3R0sXM09M%2C_%3BA25tdOV-xt9MuM%2C0TtYRIt7-db60M%2C_%3B3uKEL4YA9PcpOM%2CPOroubn_gRTtuM%2C_%3BGB9M-0ZFt9ukeM%2C0TtYRIt7-db60M%2C_&vet=1&usg=AI4_-kTW5zYJOcOVnnlVQr6ryTjMcVlnAw&sa=X&ved=2ahUKEwivzt2Hyub0AhWEoVwKHbv9CBkQ9QF6BAgYEAE#imgrc=rjOEDmaxns_TQM

 

[Welderpaul]

Anyone know what this pumps?

 

[Kayos]

Anyone know what this pumps?

View attachment 323506

Thats the pump for the dhw and maybe the ufh, unless that has a pump on it?

 

[Welderpaul]

Thats the pump for the dhw and maybe the ufh, unless that has a pump on it?

A plumber suggested turning it, clockwise, right up

Should i be looking at the UFH manifold for a problem?

All the levers on the zone valves move about. Problem is the UFH naturally takes so long to heat the screed up from cold it's going to be difficult to know when it starts working

 

[Kayos]

A plumber suggested turning it, clockwise, right up

Should i be looking at the UFH manifold for a problem?

Can't see it clearly but it looks like a multimode pump, ufh is usually constant flow, but full power is always a good option

 

[dobbslc]

Can you find where the UFH pipe go into the floor and feel them at that point, they should feel warm fairly quickly.
Is there a seperate thermostat that does the UFH that's has been knocked or turned down or maybe gone faulty.

 

[Mikes]

The pump in the 2nd picture is installed incorrectly. the shaft should be horizontal of at the most very slightly above horizontal. As installed, it will wear and fail.
Without being able to see the whole system, would suggest it's a zone valve or its associated controls that have failed.

 

[Sparky666]

The pump with variable control is likely the underfloor, possibly rads as well. wouldn’t adjust at this stage as it could be set for the size of the system, the other pump looks like its hot water cylinder as there is a stat off the pipework.
the white fronted valves at the base of the photo could be for the underfloor heating & could be the issue Or the stat has failed.
could try to draw out the system on some paper to get an idea.
without being able to see the system it’s difficult to point to one part.

 

[voipio]

Can't see it clearly but it looks like a multimode pump, ufh is usually constant flow, but full power is always a good option

Looks like a Wilo Yonos PICO, with the motor head "upside down".

 

[gaz1]

A plumber suggested turning it, clockwise, right up

Should i be looking at the UFH manifold for a problem?

All the levers on the zone valves move about. Problem is the UFH naturally takes so long to heat the screed up from cold it's going to be difficult to know when it starts working

a quick view

this zone valve apears to control the floor cant really tell but apears to go right then down towards your double thermostats



if that valve is working you will know as it will heat up on the pipe other soide of it unless its return flow zone valve

if the flow is where your thermostats are then you can check by putting your hand on the pipe on the flow to the floor



when trying to take photos of piping try and get a wider picture so pipes can be followed for the flow of them

your photos are hard to follow the flow direction

 

[voipio]

The plumbing in our last place helpfully had labels attached to the pipes, indicating flow direction and function e.g. boiler out / return, which greatly simplified troubleshooting the system.

With the system all off, are the manual valve activation levers floppy, or is resistance felt?

The pipe insulation near the bottom of the image shows possible evidence of a leak. Might that have affected something? Does the heat pump thermal tranfer loop have the correct pressure?

What is the make and model of the air source heat pump? The installation manual ought to contain some plumbing and wiring diagrams that might help fill a few gaps in understanding how it all goes together.

 

[Welderpaul]

Thanks for the assistance chaps, very much appreciated.

The valve with the red ring below was goosed so a simple swap over of the actuator and it was working again. This brought to light a few other issues though, mainly down to the design of the air source heat pump, its 9KW, but rated at 7 degrees, not -3, so struggles in this weather. There's also no balancing tank so the heat pump is being asked to do too much and ices up. The immersion is then having to take over and looks like it is doing far too much of thevwork.
Warm for now, so i'll book it in in January for some more work.

 

[Mikes]

If the heat pump is icing-up, the defrost cycle hasn't been properly programmed. When the coil starts to ice, the heat pump should reverse itself which effectively makes the coil warm and melts the ice. Ask your installer to check it out. It's one of the worst problems with single air source heat pumps. Defrost time needs to be set to an absolute minimum otherwise it really starts to effect the heating. There's some air source heat pumps outside our local station which are always iced-up. Such an easy fix but unfortunately nobody ever does it!

 

[Matchless]

And this is the bright new future for home heating............ log burner anyone?

 

[Kayos]

And this is the bright new future for home heating............ log burner anyone?

No it isn't

10 years and all these air source units will be swapped for ground source, we design ours on -3 with a 22 deg internal temp