Y plan question

[ubermik]

I waded through the other Y plan threads I could see but couldnt find one that seemed to be asking the exact same thing

Right up front I am what seems to be termed on the forums as a "messer" I guess, nearly 30 years worth of electrical installation and alarms but in the process of trying to learn basic plumbing and heating (NOT gas lol) in my spare time just so you know my level

Anyway, the question is quite simply this. I have a baxi back boiler a Danfoss 3020p controller and a Yplan system where the hot water wont work by itself

The 3020p doesnt have a HW off signal which knackers all the Y plan wiring diagrams I've seen so far.

As I am not getting JUST water or JUST central heating I am assuming that rather than a diverter valve I must have a three position valve in the system and that there must be another signal that can be used instead of a HW off signal

So my first question is a broad one. Based on the information here is this a reasonable fault for a CH novice with reasonable electrical experience to try and cut their teeth on?

Assuming thats a yes my second question would be is it a reasonable assumption that I have a mid position valve based on the heating and water both working together?

And lastly, if that is a reasonable assumption does anyone have any Y plan wiring diagrams that show methods of faking the HW off signal as I only have ones where the controller provides a HW off signal rather than me trying to reverse engineer the entire wiring diagram from the loom


Thank you in advance

 

[Dan Robinson]

I have a baxi back boiler a Danfoss 3020p controller and a Yplan system where the hot water wont work by itself

Are you sure you don't mean heating?

 

[dcawkwell]

I don't know the programmer you are using.

The simplest solution is work the 3 port valve as a diverter valve.
By joining the two wires together grey and white it will divert to central heating when central heating is required. Otherwise it will return to hot
water.

Otherwise, if you want to create a hot water off signal a simple relay will do that
for you. I'm surprised as doing electrical installation you haven't come across
one of those in 30 years. That is all your timer/programmers really
are anyway.

 

[ubermik]

I have a baxi back boiler a Danfoss 3020p controller and a Yplan system where the hot water wont work by itself

Are you sure you don't mean heating?

I'm wary of answering incase this is some kind of trick question for ridiculing noobies lol

But nah, the controller gives me two choices, water only or water and heating.

When set to water and heating the universe is a fluffykittenfest filled with rainbows and unicorns. But set it to water only and you get water only,,,,,,its cold lol

So with the summer approaching this would mean having to have the radiators working to get hot water

The 3020p only gives a CH and HW signal and gives the choices of Water and heating/water only on one switch and on, off and timed on the other

So theres no option for heating only which did seem odd tbh

And dcawkwell, yeah it is a bit embarassing, but tbh I have until recently just looked on anything heating related as unknown and have avoided it like the plague rather than dabble in things I didnt understand. So I've just left it to plumbers to the extent of even avoiding wiring up thermostats lol

Last year I decided to have a stab at plumbing in more than just a shower, then a bathroom, toilet, moving a couple of rads here and there and when I realised this was knackered figured I've been avoiding the bit that I should actually find the easiest once I know the basic building blocks the longest which is a bit dumb in retrospect I suppose

 

[Dan Robinson]

it is a serious question bud. Because... you are contradicting yourself.

When set to water and heating the universe is a fluffykittenfest filled with rainbows and unicorns. But set it to water only and you get water only,,,,,,its cold lol

I'm not taking tthe P just yet .

If you are wanting heating only, them you'll really need a different programmer, and an extra cable betwixt it and the wiring centre next to the valve.

 

[doitall]

So what is the make/model of the mv and how many wires. The colours would be good as well

 

[ubermik]

it is a serious question bud. Because... you are contradicting yourself.

When set to water and heating the universe is a fluffykittenfest filled with rainbows and unicorns. But set it to water only and you get water only,,,,,,its cold lol

I'm not taking tthe P just yet .

If you are wanting heating only, them you'll really need a different programmer, and an extra cable betwixt it and the wiring centre next to the valve.

I probably didnt explain it very well

But theres a setting on the controller for water only, when you select that it doesnt heat the water at all

But when you set it to water AND heating both the rads and the water in the tank heat up

So the problem is with the water only setting

I havent gotten to the valve yet Doitall, tbh I just wanted to check this wasnt a more complex level of fault than it seemed before having a stab at it tomorrow incase theres some layer of complexity I'd missed if that makes sense

Plus the lack of a HW off terminal made all the wiring diagrams I have for Y plan redundant too lol, but it would probably be a good exercise to try and figure out how its wired as I go but tbh whoever wired it certainly wasnt trying to get marks for either neatness nor organisational skills it looks like they just threw a huge knotted lump of wires at the house and by pure chance they just fell into the right place as its a total mess to look at so I'm tempted to strip a lot of it out and rewire it morely betterlyish lol

 

[doitall]

Forget Y plans you can't have it, unless you want a repipe

What 2 port valve do you have then

As for ripping the lot out, I wouldn't advice it unless you want to get someone in the put then back, you are not talking conventional.

 

[ubermik]

Forget Y plans you can't have it, unless you want a repipe

What 2 port valve do you have then

As for ripping the lot out, I wouldn't advice it unless you want to get someone in the put then back, you are not talking conventional.

There already is a Y plan though isnt there? Its a 3 port valve not a two port, but I wont know the actual part number till tomorrow

As it seems to do water and heating at the same time I am only guessing that implies its a 3 position valve rather than a diverter but I will know that and the wiring tomorrow which I think might be a honeywell


As for replacing the wiring, its really a total mess. But once I have reduced it to a wiring diagram ripping it all out and doing it more neatly at the controller end wont be an issue in the slightest as its nothing more than a supply, two switched lives and I suspect the wires for the roomstat and the wires feeding the pump, valve and boiler

The wiring at the other end in the airing cupboard will be a bit more involved I'm guessing, but that isnt on show so I'm not fussed about redoing that end

 

[Dan Robinson]

Still not in the P taking mode....

You are looking at heating electrics through an electricians eyes.

Post back with some details, an maybe even some pictures, and we will see what we can come up with .

 

[doitall]

At best if the boiler is fully pumped you are looking at a W plan.

The most likely is some ones stuck the valve in and not had a clue how to wire the wrong timer.

At worse the boiler has been converted wrongly and could be dangerous.

Whatever it's the wrong timer for an Y plan.

 

[ubermik]

Have to pop out in a bit so I wont try and decipher the exercise in basket weaving that passes for the wiring till I get back but inside the airing cupboard theres

Honeywell L641a1005 stat

and a

Honeyell "Sundial Y plan 3 position diverter valve"

but I cant see any part number just the name

Doitall is seemingly on the right track it seems when I got to the valve there was a bit of earth wire holding the manual lever into the manual position which would have been done the autumn before last I'm guessing when the landlord had it serviced. But as I was working away most of the summer I seem to have skipped through all of last summer without realising the problem


As for looking at it through an electricians eyes I totally get that having made similar comments about how electricians approach installing alarm systems or data network cabling so yup youre totally spot on there lol

I wouldnt even plumb my own showers in for years because "EEK" its water lol

The pipework also doesnt mirror the text book pictures but I suspect very few installations ever do, so I'll trace the way its wired, get a better idea of what each pipe is doing/where its going and come back

But after looking at the valve it would seem the motor or one of the micro switches might be the problem but I'd still like to know how they have gotten around not having a HW off signal for a 3 way valve so figuring out the wiring is still worth doing

UPDATE

The plot thickens

I just noticed the tank stat was at nothing, so with the lever moved to auto I turned up the stat temp and the motor kicked in and boiler lit with the controller set to water only so I'm not even sure there IS an actual problem now (other than not having a HW off signal

I'll leave it running on water only and see if it switches off at temp and whether the radiators stay cool as they should to try and figure out why the level was wedged over into the manual position

Thank you all for your input so far btw and for putting up with my noobiness I do appreciate how frustrating it can be trying to decipher the witterings of a total beginner

 

[Dan Robinson]

Dude, at least you understand your limits, which is a good thing

Sounds like your landlord has had a real bodger in there.

Keep us posted.