Heating issues after building work (Intergas Eco RF / Nest)

[DaveApp]

Hi.

We’ve just had some building work done and now struggling with central heating problems.

Our setup is that we have an Intergas Eco RF 24 heating the radiators (controlled by Nest) and unvented cylinder (with its own thermostat attached to the side). The hot water is favored over the radiators, so the cylinder is heated before the radiators will warm up.

Last week our Nest Heat Link was moved from being wall mounted to being put within the new kitchen cupboard and since then, we’ve not had any central heating. When the hot water is used and the cylinder cools down, it’s thermostat calls for hot water and the boiler starts working to reheat the water. However, when the Nest asks for hot water for the heating the boiler does not respond in any way.

Originally I thought that the problem was with the Nest Heat Link, but I’m not sure about that now. I’ve got the thermostat and Heat Link side by side and when the Nest asks for heat, the Heat Link clicks as if it’s switching on, but nothing happens.

If I press the button on the front of the heat link to override the central heating, the two lights (heat and water) illuminate, but again the boiler does not respond.

The Heat Link is connected to the boiler via the OpenTherm connections and the connections have been checked so there’s no loose wires.

I’m now coming to the conclusion that this may be an issue with the boiler rather than Nest, but thought I’d ask to see if anyone with some experience has any Idea of what I could try to isolate or fix the problem?

Thanks in advance, Dave.

 

[Dan Robinson]

More likely to be the Heatlink or a setting on the Nest.

Make sure the Nest configuration is set to OpenTherm for both heating and hot water.

 

[DaveApp]

Thanks for the response Dan.

I've changes the settings to OpenTherm, but now I'm getting a H73 error (There is a wireless connection but OpenTherm is not detected. Check your installation).

Don't suppose you know of a way to override the Nest and get the boiler to provide us with some heating while I try to sort this out???

Thanks again,
Dave.

 

[Dan Robinson]

You can put it into service mode, but that will only give you a few minutes. (hold the spanner button and press + .

Get the installer to check his connections to the boiler. Sounds like he's not connected it up right.

 

[DaveApp]

Thanks Dan.

The HeatLink was moved by my builder while installing the kitchen who kind of shrugged his shoulders saying that he thinks the HeatLink has broken and then went home for the weekend .

Looking at the wiring, there's a single twin wire going between the HeatLink and the boiler which from what I can gather should be correct.

The wiring connects as follows:

Nest connection OT1 --> Boiler port 12
Nest connection OT2 --> Boiler port 11

Could the problem be that these have been put back the wrong way around???

Cheers,
Dave.

 

[picasso]

What valves are you using (s plan or y plan) ?

 

[DaveApp]

It's a Y plan I believe.

We have a single valve diverting between the cylinder and radiators.

 

[Dan Robinson]

Plumbed with port A to the cylinder? I take the boiler doesn't go to status 5?

 

[Dan Robinson]

Could the problem be that these have been put back the wrong way around?

No, but, either the heatlink is fried, or the OT terminals in the boiler are.

 

[DaveApp]

Thanks again for your continued support here Dan.

Plumbed with port A to the cylinder? I take the boiler doesn't go to status 5?

The boiler goes to status 5 when the cylinder asks for heat - we have no problems with hot water. Just that nothing happens when the nest asks for the heating for the radiators.

No, but, either the heatlink is fried, or the OT terminals in the boiler are.

And could that have been caused by rewiring the HeatLink the wrong way around?

 

[Dan Robinson]

Boiler should go to status 6 when heating the cylinder. Status 5 is for heating. Someone has screwed a setting up.

Parameter A should be 6, Parameter 1 should be 1.

Diverter valve should be wired to pin 5 and the ports plumbed A to cylinder, B to heating.

 

[DaveApp]

Thanks Dan.

I think it's fair to say that we've just met the limits of my understanding and I'm going to have to give the installer a call to come and have a look.

At least I can conclude that I've not missed anything basic.

Really appreciate you taking the time to help.

All the best,
Dave.

 

[Dan Robinson]

No worries, let us know how you get on.

 

[Ian H]

On our boiler, before I got a programmer, the guy put a link between to points on the board and that gave heating.

 

[picasso]

On our boiler, before I got a programmer, the guy put a link between to points on the board and that gave heating.

If the link was to be fitted on this boiler it would just run uncontrolled overheating the hot water and or central heating.