Why won't my heating work but hot water does?
I've installed the Tado Starter kit V3+
I have an Ideal ICOS M380 boiler.
The cold water tank's in the loft and the hot water tank and wireless receiver in 1st floor bedroom cupboard, the boiler's downstairs in the kitchen. The system thus is gravity fed and 'Y' plan wiring.
Prior to installing the wireless receiver, we had a Drayton Lifestyle LP522 programmer that serviced both hot water and heating.
This replaced my (ancient) existing wired Drayton thermostat. It had been connected with and only had, 3 wires. I disconnected each wire and put the supplied connector blocks one on each wire. I then fitted the Tado wireless thermostat over the top.
I followed the installation instructions to the letter, and double/triple checked each stage.
The receiver was wired to a Y plan and then I changed the setting to the 'blue' gravity fed setting.
The hot water works as it should and 'fires up' my boiler but there is no heating whatsoever. The thermostat appears to be working inasmuch as it seems to be sending a signal to 'fire up' my boiler but even when the boiler does make an initial attempt to work, the burner light does not continue to stay on for longer than a minute or 2. It then just flashes on/off. I've never had a problem with it supplying both the heating and hot water before. Apparantly this means its 'receiving a call for heat but is already within it's running temperature range'. By the way, I don't actually understand what this means per se, but as I've never had a problem before so don't see why it would be a problem now.
I've gone through loads and loads of items posted on the support/community pages and still cannot work out what's wrong. The only thing I've found that's incorrect so far is that the thermostat has a tick to say the EK is being used which it isn't and there's no option available to changing this.
I've reset my boiler, removed then re-added the internet bridge/receiver/thermostat...
I'd be so grateful for any help as I'm freezing to death here!
Comments
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Is the Drayton programmer still wired in, and does your boiler have any kind of internal timer or programmer fitted?1
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I think you’re getting a little confused with what system you actually have.
If you have a 3 port, mid position, valve fitted you have a Y system. So wire it up as a Y system. Strictly speaking a gravity system is a C system. There was also a W system, but neither of these are used anymore. What you have is a cold water tank in the loft that feeds the hot water tank using gravity. That’s normal for a Y system.
There are 3 things that can cause your problem. It could be incorrectly wired, the actuator motor could have failed or the valve is stuck.
Make a note of which pipe coming out of the valve gets hot when you select hot water. It should be the B port.
Turn the hot water off and select Heating only. You should be able to hear the actuator changing position and the boiler firing up when it stops. If the actuator doesn’t move it’s either a faulty motor or incorrectly wired. If the actuator does move and the boiler fires up, check if the hot water circuit, port B, is getting hot. If it is you have a stuck valve.
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Thank you both for the comments. So you've sussed that I'm a novice to all of this!
I did wire it up for a Y system, sorry for the confusion. I confess I don't know what an actuator is and also don't understand what you mean by valves and ports. I think I've obviously bitten off more than I can chew 🤔. It looked so simple! I have pics but not sure if I can share them here?0 -
Y plan heating systems have a valve that is separate from the boiler and diverts hot water either to the cylinder or to the radiators. The actuator is the motor that moves the valve. Was your heating working before you installed the Tado? Is the Drayton programmer still wired in?
You can post photos on the desktop version of the forum.
https://www.warmzilla.co.uk/blog/s-and-y-plans-explained/1 -
That’ll give you an idea what you’re looking for.
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Thank you for your patience!
I've uploaded pics that I think may help explain my situation.
All old Drayton equipment removed and/or decomissioned.
Hope this helps you to help me
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I can’t see anything immediately wrong with it but people who know more than me like @GrilledCheese2 @Montage @wateroakley might be able to.1
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The mystery item, the white cable coming from the fused spur, will be your immersion heater.
Just for giggle it might be useful for you to know how that lot works.
You’ve got hot water, so I’ll start with that. The hot water comes from the boiler and is pumped around the system by the Grundfos pump. It goes into the base of the 3 port valve and is forced up out of the valve into the cylindar coil and out through the pipe at the bottom of the tank, where it returns to the boiler.
When you have heating only selected the water exits the valve through the pipe with the bend in it (the one at the bottom) and returns, via your radiators, to the boiler.
When you have both heating and water on at the same time it sends heated water through both sides of the valve. This is achieved by a ball inside the valve moving to either block the heating side, the bottom port (when hot water is selected), the hot water side, the top port (when heating is selected) or to take up the mid position, I.e it opens both ports at the same time, when both heating and hot water are needed.
The box with the danger label on it…. Have you checked to make sure there’s nothing in there that’s com adrift? I.e all of the wires that go to the valve motor and the thermostat are connected.
Good lord it’s nearly my bed time. How time flies when you’re boring people to death.
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Think you’re being a bit hard on yourself @Mr_Fruitbat1 , that’s useful info.0
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@Aisha I think this is your problem.
"This replaced my (ancient) existing wired Drayton thermostat. It had been connected with and only had, 3 wires. I disconnected each wire and put the supplied connector blocks one on each wire."
Try connecting together the wire on terminal 3 to the wire on the Live terminal. The Neutral wire must stay isolated.
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@Mr_Fruitbat1 thank you so much, we've only recently moved in and I've always had nice new combi's before and never had any problems. I appreciate the time and effort you've put into explaining it all for me in your post. @johnnyp78 I appreciate your input too lol.
@GrilledCheese2, just to clarify you're referring to the old Drayton thermostat I had in my lounge and is pictured below? Hadn't taken a pic prior to removing it so just took one now to show how I decommissioned it using the connector blocks.
Are saying to put the live and the earth into 1 connector and leave the neutral as is?
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I wasn't expecting an Earth wire. Assuming that wire is definitely Earth then it looks like there is no Neutral. The black wire is Switched Live and the red wire is Live. So connect red and black together in one of those Wago connectors.
It's the Earth that needs to stay isolated.
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Black is Neutral isnt it? Red is Live, Green and Yellow is Earth. Our house was built in the 1990's so is the old wiring. Dad was a Sparky and I'm 60 so remember the old wiring lol.
We're in the UK... Sorry, had the dangers of electrics and need for safety 'drilled' into me from an early age with Dad being an electrician so hence the double checking!0 -
Your original thermostat acted as a switch, connecting two wires together to turn the boiler on. Assuming the red wire is Live then one of the other wires has to be the switched live. The black wire should have a red sleeve to indicate it is no longer Neutral, but sometimes this sleeve is omitted.
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@GrilledCheese2, did as you said, boiler went on for about 20 seconds then everything went dead! The boiler doesn't turn on after I've switched it off and the Tado receiver is totally dead too. Nothing turning on!!
As such I put it back to how I had it before with each of the wires individually isolated behind the tado room thermostat. Still nothing, nothing turning on, no apparent power to the receiver, boiler etc0 -
Doing as you said blew the fuse that controls it all :/ changed the fuse and now its all back on again but still no heating0
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The reason I suggested connecting those two wires is to bridge the circuit for the CH control. Previously your time clock had to switch on and the thermostat had to switch on to make the circuit which turns on the motorised valve for CH. Now that the receiver is doing both time and temperature control those wires need to be permanently connected to make the circuit. I attach a diagram so you can follow the wiring from CH On in the receiver to the valve. This shouldn't have caused the power failure, but obviously something is wrong. Have you tried replacing the 3A fuse in the switched spur? The boiler running for 20 seconds suggested a fuse has slowly blown due to a slight excess of current, not a total short circuit.
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Just seen your update. Glad to see it was just the fuse. Not sure what else to suggest. I'm convinced you need to connect the two wires and something else is wrong. But don't know what else to suggest, your wiring for the receiver looked fine.
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Can you take the cover off the box with danger on it and take a picture so we can see the wiring.
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Here's a pic of the 'danger' box contents
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This is the plug that blew
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This is what I'd done that ultimately blew the fuse, I presume I'd understood your directions @GrilledCheese2
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@Aisha the wiring of the wago connector is fine. When a heating system is blowing a fuse slowly the culprit is often a failing motor or a water leak. But probably best not to consider this at the moment, as your system was previously working.
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Thanks, I can see where your problem is now.
The white wire, that is in terminal 5 needs to be connected to the Black wire in terminal 4.
The reason GrilledChees2 asked you to join those cables is the red cable that is currently connected to the black cable on terminal 4 goes to your old thermostat and should return via the black cable to join with the white cable pictured above. It clearly doesn’t do that as the fuse blows.
It very difficult to see from the picture, but I’m assuming that the black cable that’s connected to the brown cable is the one that goes back to the thermostat.
What you need to do is this.
Make sure the black cable in terminal 4 is the one connected to the CH NO in the Tado box
disconnect the red cable on terminal 4
disconnect the white cable on terminal 5
put the white cable where the red cable was.
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@Mr_Fruitbat1 are you talking about moving the wires around in the 'danger' box? I ask given that's the only thing with white wires in.
If its not too inconvenient, could you screenshot and mark the parts/terminals that need to have wires moved in/out of?0 -
I set up my system 2 weeks ago and had the sam problem, you are experiencing.
I also have a gravity-fed system - Colder water tank in loft - upstairs hot water cylinder - downstairs in the utility room the boiler and programmer and Y plan wiring.
Following the instruction on the app it mentioned that you might have a gravity-fed system and require a gravity driver, which the installation team wil install on your system.
I contacted the installation team by emai and the following day they installed the gravity-fed driver and it messed up my system - heating and hot water light appeared at the same time, causing only the hot water to come on and no heating.
Usng the emergency email I asked them to remove the gravity-fed driver (it was on the same day) and the system worked as normal after resetting the boiler, no configuration necessary. I have all white lights.
It seems like the tado does not recognise the UK gravity system with Y plan wiring.
Hopefully this will solve your issue.
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In this case a picture doesn’t paint a thousand words.
From the left, count to the 4th terminal, it has a black wire at the top and a red wire at the bottom, remove the red wire.
Remove the white wire from the 5th connector and insert it where you just removed the red wire from .
No idea what a gravity driver is, but that’s not your problem. Your problem is being caused by incorrect wiring.
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Correspondence with Tado installation staff - read from bottom to top about the query about graity-fed system.
Hi
That is good news. We will just leave it like this and in case you notice it needs a different driver, please let us know.
Kind regards
Alex
Alexander from tadoOn Tue, Jan 3, 2023 at 08:33 PM,
Hi Alexander,
Thank you very much for the quick response and sorting out the issue. It's working again.
My system is Y plan, and I have a cold water tank in the loft and HW Cylinder downstairs in the airing cupboard. That's why I thought I have a gravity-fed system.
At least it's working with the current configuration.
Mail Attachment
On Tue, Jan 3, 2023 at 08:03 PM, "Alexander Bauer" <alexander.bauer@tado-844a35e31252.intercom-mail.com> wrote:
Hi
I do not see why it is not working. But it is normal that both LEDs light up, when heating. Gravity fed means it always closes the hot water relay together with the heating relay in order to have the heating come on.
I have reverted back to normal relay, now.
Let me know, in case you need anything else.
Kind regards
Alex
On Tue, Jan 3, 2023 at 07:21 PM, "+447728216593 Aircall new user" <> wrote:
Voicemail on UK-Installer (ZD)
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@royi Thanks for the info, yes that is/was my assumption too.
@Mr_Fruitbat1 Also thank you...
I will hopefully try and do it tomorrow although will be out for most of the day. I prefer to do things like this during daylight hours so may not be able to do it until Sunday. I will let you know when I've done it! In the meantime I will maybe go buy some thermals! Even resorted to turning the oven on and leaving the door open!
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I think there's some confusion here about gravity systems. It does not refer to a water tank in the loft, but to gravity circulation of water through the pipework (instead of using a pump). Cold water is heavier so it sinks under gravity, pushing warmer water upwards. These systems were phased out in the UK ~40 years ago. The Y Plan system is fully pumped, meaning water is pushed through both the CH and HW pipework. No longer is there a requirement to arrange the pipework in a manner that gravity will circulate the water between boiler and cylinder.
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