RF Mains link kit on a heating system.

[Soulsurfer]

Hey all,
I have a heating system to play around with as it's been not working very well, heating non stop until house was like a sauna etc.. and guy wants to fit a nest that he bought. He's a bit keen on going all smart home so I'm thinking of going to do a Loxone course.

Problem so far is that the nest is 12V so I'm thinking of re-using the existing 3 core to the room stat and connecting to the nest heat link hub to make 12V instead of 240V, but as cylinder stat is out the way upstairs with a route full of asbestos I need to get a link between garage (hub) and the airing cupboard in the house without running a 3 core as existing is just 1 x twin supplying the cylinder stat and hot water valve next to it.

A mate has suggested the mains link over RF to basically give a remote command for the heat link / hub. Anyone used them ? rate them ?

Thanks in advance..

 

[Leesparkykent]

I've used them and think they're a good bit of kit. If you grab a copy of the latest professional electrician magazine they have a voucher towards the back pages for buy one get one free.

 

[Soulsurfer]

I've used them and think they're a good bit of kit. If you grab a copy of the latest professional electrician magazine they have a voucher towards the back pages for buy one get one free.

Never heard of that mag is it a newsagent job ?

 

[Soulsurfer]

Found site online but just looks like an online only, can't see how to buy etc..

 

[Ian1981]

Never heard of that mag is it a newsagent job ?

It’s in all the Electrical wholesalers on the counter, free to the trade.

 

[Soulsurfer]

Ah cheers mate, we don't get them here ! Jersey issues !

 

[Leesparkykent]

Ah cheers mate, we don't get them here ! Jersey issues !

here you are mate

 

[Soulsurfer]

here you are mate

View attachment 39200

View attachment 39201

Lee Sir you are a legend mate, I ordered one, well 2 sets and got the offer code one discounted and VAT off too and both sent today to Channel Islands for £104 ! A beer is owed buddy Thanks, Matt.

 

[Leesparkykent]

Lee Sir you are a legend mate, I ordered one, well 2 sets and got the offer code one discounted and VAT off too and both sent today to Channel Islands for £104 ! A beer is owed buddy Thanks, Matt.

Happy days mate, glad to help.

 

[Soulsurfer]

Happy days mate, glad to help.

While you're on a roll mate ! Can you have a little check over a change I'm trying to achieve with an old boiler to a nest stat and it's the job where I may or may not need to use a set of RF Mainslink.

I went today and because it was a horrible mess all jumbled into a single old pattress box I took apart and started again with the nest and heatlink plus a danfoss wiring centre.

The wiring I've done so far is as follows:
All usual cabling to the heat link and then I have 6 on heat link calls for hot water into a terminal on wiring centre and connects to one core of a twin I have (that originally took a L + N to cylinder cupboard to feed Com on cyl stat) then from cyl stat was straight onto valve actuator up in cupboard and picked up the neutral for the valve.
Now I have used the twin going to cylinder to feed the cyl stat com from the heat link call then back down to wiring ctr on the blue core when the cyl stat closes. I was then thinking I need to use rf switch to send a s/l and n to the valve upstairs, but thinking about it, could I not just come straight from the nest call for hw to the cyl stat com on the existing twin and then when stat closes feeding the brown of valve motor and use the N on that twin for the valve to open ?
But do I need another cable to call boiler in for hot water ?

Other issue is heating valve is an old one and I don't think working correctly or if it will work with the nest.
Thought about changing for a Danfoss HPA2 spring return or similar as this old Sunvic has a yellow to open, white to close and an orange (not in use) but when nest calls for heating onto the yellow to valve the valve opens and the white ( apparently to close the valve via 240V too) stays at 240V also. Tried feeding the white from satisfied on heat link to shut valve when not calling but it doesn't seem to work.

My head hurts now... First boiler on my own to sort / modify.

 

[Soulsurfer]

Think I've got it worked out.

 

[Leesparkykent]

Think I've got it worked out.

Hi mate, sorry I didn't reply I've been flat out....If the hot water valve is next to the cylinder along with the cylinder thermostat then you need perm live, neutral, earth, switched live from 6 on heat link to common on cylinder stat, normally closed on cylinder thermostat to brown of the valve and orange to fire the boiler. Where is the heatlink in relation to the cylinder? What about the CH valve...where is this located in relation to the heat link and cylinder?

 

[Soulsurfer]

Hi mate, sorry I didn't reply I've been flat out....If the hot water valve is next to the cylinder along with the cylinder thermostat then you need perm live, neutral, earth, switched live from 6 on heat link to common on cylinder stat, normally closed on cylinder thermostat to brown of the valve and orange to fire the boiler. Where is the heatlink in relation to the cylinder? What about the CH valve...where is this located in relation to the heat link and cylinder?

Nice one then mate that's basically exactly what I've done, ripped out all the old and wired new. The Heatlink is in the garage next to the wiring ctr newly fitted, the boiler there too and the Htg valve is an old Sunvic / Satchwell there too as the flow leaves the boiler horizontally on pipe there, has a yellow to open on 240, white to apparently close it again. This valve does not work well at all but was logged as fitted in 1983 ! so I plan on Monday to replace with an HPA2 or 4043 Honeywell and spring return.

Cylinder is upstairs in house with a t & e feeding and supplying neutral up to it only. (no 3 core for a sw line !)

Originally this was fed directly from load side of dp switch so I have reconnected this twin to the wiring centre to take a switched line from 6 on heatlink call for dhw, then a neutral too of course as you have also said- now feeds cyl stat and then out onto the dhw valve which is a new Danfoss HPA2 spring return 2 port.

As it was the boiler sat with a switched line from roomstat and link to pump for htg only and if cyl stat closed the valve would open and just let hot water seep through coil by gravity feed and no real control other than boiler internal stat.

There lies my pain issue ! no switch line from cylinder (no extra core / 3 core flat etc..) the route is riddled with asbestos too so hence my idea of rf mainslink at cylinder position, picks up feed and say I also feed grey on valve micro, then orange of valve on to rf and other rf down at wiring ctr / heatlink to feed out on to boiler fire when dhw valve opens fully, giving more control on hot water.

 

[Leesparkykent]

Yeah I've never really been a fan of momo valves. Don't sunvic make a spring return valve that will directly replace the momo valve head without having to drain down etc? Is the cylinder vented or unvented?

 

[Soulsurfer]

Yeah I've never really been a fan of momo valves. Don't sunvic make a spring return valve that will directly replace the momo valve head without having to drain down etc? Is the cylinder vented or unvented?

Vented cylinder, and it's sound the other two valve heads fit straight onto existing valve.