Hive Wiring to Oil Boiler

[bpaddy]

Hi,

I have moved my oil boiler out to the garage and removed the old thermostat and timer in the house completely. I have electric in the garage but not sure how to connect hive mini thermostat to the boiler.

Currently there is a socket for boiler and separate socket for pump - any help appreciated!

Thanks,
Paddy

 

[Exedon]

Have you any motorised valves on system?
Picture of boiler from further out would be useful.

 

[CBW]

When you say removed the old thermostat and timer completely, did you disconnect in the wiring center if applicable? Also, as above.

 

[stem]

If I had to guess, I suspect that you may have a system that is plumbed in a way such that the boiler operates alone to heat just hot water, and then when central heating is required the pump comes on as well. With this set up it's not possible to have the heating on, without the hot water being on at the same time. Can you confirm that?

Currently there is a socket for boiler and separate socket for pump

It is unusual to have a boiler with external controls (programmers & thermostats) and have the boiler and pump fitted with plugs . But again if I had to guess I would imagine that originally the there were a couple of sockets wired to the external controls that the pump and boiler were plugged into. Can you confirm that? Presently, provided that it's safe to try, do the boiler and pump work when plugged in to the mains?

So, as has already been said we need more information. A description of the type of heating system the boiler is connected to would be a start, i.e. pumped central heating with gravity circulation of hot water / fully pumped (Y-Plan) / fully pumped (S-Plan) / something else? for example maybe it's heating only, without an attached hot water system.

I don't have any experience with the Grant Euroflame, but I believe that it comes in several different variants and that the models that have changed over the years. If you have an installation manual for the boiler, a photo of the wiring diagram for the external controls would also be useful.

Finally if it does have hot water and central heating functions you will need the dual channel version of the Hive.

 

[bpaddy]

Thanks for the replies - the expansion tank, pump and oil line needs plumbed in.

No motorised valves - the boiler just heats up rads and hot water tank (in hot press) we just had a timer clock and thermostat in our hall before. All that has been disconnected but I think it basically just turned off/on a double socket outside in the old boiler house.

I am going to put a double socket in garage beside the boiler but just need help on best way to set up for the hive.

 

[stem]

OK, provided that it used to work as per my previous post below, here's how to proceed. If the hot water is pumped and not heated by natural gravity circulation then it will be different, so you need to post back and let us know if that is the case.

I suspect that you may have a system that is plumbed in a way such that the boiler operates alone to heat just hot water, and then when central heating is required the pump comes on as well. With this set up it's not possible to have the heating on, without the hot water being on at the same time.

Then the Dual Channel Hive terminals are as follows:

Mains supply to (N) & (L) make sure to use correct fuse as per the manufacturers instructions.

Boiler L to Hot Water on (3) Boiler N to (N) - This is the mains supply to the control module that includes the boiler thermostat

Pump L to Heating on (4) Pump n to (N)

All earth wires to 'earth tether'

Set the Hive to operate with a "Gravity-fed and part-pumped system" the Hive instructions tell you how to do this.

 

[bpaddy]

OK, provided that it used to work as per my previous post below, here's how to proceed. If the hot water is pumped and not heated by natural gravity circulation then it will be different, so you need to post back and let us know if that is the case.



Then the Dual Channel Hive terminals are as follows:

View attachment 314383

Mains supply to (N) & (L) make sure to use correct fuse as per the manufacturers instructions.

Boiler L to Hot Water on (3) Boiler N to (N)

Pump L to Heating on (4) Pump n to (N)

All earth wires to 'earth tether'

Set the Hive to operate with a "Gravity-fed and part-pumped system" the Hive instructions tell you how to do this.

Thank you so much - if it is heated by gravity do I need a single-channel hive?

Also - can I just ask - if I can't heat rads/water separately, how come I need a dual-channel? (is it just to wire the boiler and pump in separately)

 

[bpaddy]

For info - the only way to heat hot water before was immersion heater or having the full heating on.

We have a cold water tank in the attic - so does that mean it is gravity circulation?

 

[stem]

With gravity heating of the hot water, the hot water channel (3) switches 'on' the boiler only and hot water circulates naturally around the hot water cylinder. So the hot water cylinder heats up.

Then, with pumped central heating, when the heating channel (4) switches on as well, so the pump now also starts, and circulates water around the radiators. The thermostatic function of the Hive will now switch the pump 'on' and 'off' to maintain the required room temperature as set on the Hive. However, the boiler being on a separate channel will still allow the hot water cylinder to be heated.

If you have a fully pumped system, i.e. the hot water cylinder and the radiators are both pumped, then it will be different so it's important that you find out which type of system you have.

The single channel Hive is for systems that don't have a connected hot water system (ie a combi boiler) if you were to wire a single channel Hive to a system with a hot water system then when the rooms were warm and the Hive switches off the heating it wouldn't heat any hot water either.

Previously I would have expected that the timeswitch would turn 'on' the boiler and then the thermostat would control the pump, so when the thermostat switched off the pump, provided the timeswitch was still 'on', you would have hot water.

 

[bpaddy]

Afaik the heating previously - when the thermostat in the hall reached the desired temp it switch everything off (the boiler went off)

The plumber did say when moving to the garage we could get another pipe added to the system directly to the hot water cyclinder to allow us to heat water separately from the boiler but we never had it before so just left it.

Will ask him later if cylinder and rads both pumped but yes would be my guess

 

[bpaddy]

"Presently, provided that it's safe to try, do the boiler and pump work when plugged in to the mains?"

Yes

 

[stem]

Afaik the heating previously - when the thermostat in the hall reached the desired temp it switch everything off (the boiler went off)

The plumber did say when moving to the garage we could get another pipe added to the system directly to the hot water cyclinder to allow us to heat water separately from the boiler but we never had it before so just left it.

Will ask him later if cylinder and rads both pumped but yes would be my guess

In that case you can use a single channel Hive but it's not right really. When the house is warm and the Hive switches off the boiler and pump, someone has a bath or shower and the hot water is used up. In mild weather, it could be several hours before the house cools and the heating comes back on, so no hot water will be heated until it does, and then if the radiators aren't on for long it may not heat the cylinder fully....but if you've lived with it like that and it's been OK for you, then a single channel Hive will replicate what you had before.

 

[bpaddy]

If there is no pipe directly to the cyclinder - as mentioned before - is it impossible to do the dual channel hot water heating you mentioned previously. As obviously that would be better :/

If not - what way should the single channel be wired

 

[stem]

This is what I thought you might have had. Gravity circulation of hot water and only pumped central heating.

But if there is only one set of flow and return pipes feeding both the heating and hot water directly as per the diagram below, then you can't control them separately, without modifying the pipes or adding motorised valves.

To utilise a single channel Hive with a system as per the above (but with the limitations I described earlier):

Mains supply to (N) & (L) make sure to use correct fuse as per the manufacturers instructions.

Boiler L to Heating on (3) Boiler N to (N) - This is the mains supply to the control module that includes the boiler thermostat

Pump L also to Heating on (3) and Pump N to (N)

Add a link wire between the terminals (L) and Common (1)

All earth wires to 'earth tether'

As I've not used Hive with a oil boiler, I would recommend that you check the current (Amps) drawn by your boiler to make sure that it doesn't exceed the current rating of the Hive receiver.

 

[bpaddy]

This is what I thought you might have had. Gravity circulation of hot water and only pumped central heating.

View attachment 314403

But if there is only one set of flow and return pipes feeding both the heating and hot water directly as per the diagram below, then you can't control them separately, without modifying the pipes or adding motorised valves.

View attachment 314410

To utilise a single channel Hive with a system as per the above (but with the limitations I described earlier):

View attachment 314408


Mains supply to (N) & (L) make sure to use correct fuse as per the manufacturers instructions.

Boiler L to Heating on (3) Boiler N to (N) - This is the mains supply to the control module that includes the boiler thermostat

Pump L also to Heating on (3) and Pump N to (N)

Add a link wire between the terminals (L) and Common (1)

All earth wires to 'earth tether'

As I've not used Hive with a oil boiler, I would recommend that you check the current (Amps) drawn by your boiler to make sure that it doesn't exceed the current rating of the Hive receiver.

Looking at the manual for the boiler, it needs to be protected by a 5A fuse.

Will this cause any issue?