One Boiler Serving Four Properties. How To Wire Up?

[clarkey104]

Hi everyone

Please forgive any amateurish terms etc as I am a builder/property developer not an electrician.

We live in a farmhouse and have just converted an attached barn into a holiday let. We have been told by our plumber that the boiler in our house is big enough to run the water and heating to both our house, the converted barn and two more barns which will also be converted to holiday lets over the next year or two.

Now, the plumbing is all in for the new holiday let, but our electricians were unsure how to do their bit to wire in as necessary for the heating and hot water. We have three pipes to the holiday let: a flow, a return, and a cold main. We have a cylinder in the holiday let. Apparently we have a pressurised unvented system to both our house and the holiday let.

Our plumber assumed that he could get the electricians to route a 'live' to the boiler from the new holiday let to let the boiler know when hot water is needed. When all the barns are completed that would give three lives, one from each holiday let plus a live from our house totalling four in all. Our Electricians refused to do this because they said that anyone servicing or repairing the boiler in the future would perhaps not realise that this is the case and thinking they could make the boiler safe by shutting off say the house fuseboard then go on to get a nasty shock!!! They were unable to find a solution. In desperation our plumber installed a flow senser next to our boiler. it failed after a short while then another failed then a third did the same. Another, rated at 3 amps lasted longer, all was well then it too failed. When the flow sensors fail we lose all control over which heating and hot water is on and in fact they all stay on all the time!

I find it difficult to believe that the situation of one boiler serving several dwellings each with a cylinder and thermostat has not been encountered before in this way.

Does anyone have an ideas. Help greatly appreciated!

John

 

[steptoe]

simples,

use wireless programmers and stats,

it deffo wouldnt be right to have a live from a different building in another building if they are seperate installations.

 

[kerching]

You just need better Electricians to be honest

To make it safe would just require a simple Isolator with appropriate labelling

To wire it up would require a few brain cells on the part of the electrician 

To be fair, there are not of    "  electricians".  that could do,that. There are a lot that think they could......the italics and bold type are intentional!

 

[clarkey104]

Hi Canoeboy

Please could you clarify that you have given four options. Namely 1) bring four lives to boiler 240 v but use simple isolator and good labelling

                                                                                                         2)Use a volt free system

                                                                                                         3)Use a 24v system

                                                                                                         4) Use a wireless system

Many thanks

 

[binky]

ehhh, surely hot water flow is from the tank, so as long as bolier knows tank needs heating, ie a thermostat, that could be done at farm house end? Heating is a different matter, unless plumber did some clever plumbing, and it doesn't sound like he has, then you can only heat all the lets at the same time. However i do believe wireless rad stats can now be had controlled by room stat in each let, allowing occupants some individual control.

 

[Andy™]

zone valves on each, output from zone valve feeding a relay to switch volt free contacts, wired back to boiler to switch it on

 

[ProDave]

It's really simple when you break it down logically.  Here's how I would approach it:

Plumb everything with multiple 2 port valves, forget any notion of 3 port valves anywhere in the system.

Each and every heat "system" will have it's own 2 port valve.  So one for the heating circuit(s) in each "unit" one for each hot water tank etc.

The 2 port valves are controlled by local programmers and thermostats supplied from the local wiring of each unit.

Then the feedback contacts from each 2 port valve are wired in parallel and go back to fire the boiler when any system calls for heat.

 

[binky]

just re-read bit about cylinder in let, didn't spot it first time around. Again can be achieved by wireless stat on tank in let or any of the other suggestions above.

Personally i think it would have been easier to put boiler in each let, this would benefit from being ultimately more reliable - lose your boiler and house and lets will all go down together.

 

[clarkey104]

Thanks everyone

The let has got a roomstat and a programmer wired in to its cylinder already

 

[binky]

nice to see something as tickled you paddler. Apparently Einstein was an ego maniac and nasty peice of work

 

[binky]

Thanks everyone

The let has got a roomstat and a programmer wired in to its cylinder already

not a lot of use unless linked to house boiler. Some photos would be useful, contact admins to allow posting if you haven't posted 10 times already

Yes but he was clever

only when you drop apples on his head!

 

[SPECIAL LOCATION]

We live in a farmhouse and have just converted an attached barn into a holiday let. We have been told by our plumber that the boiler in our house is big enough to run the water and heating to both our house, the converted barn and two more barns which will also be converted to holiday lets over the next year or two.

Are all of these other proposed holiday lets attached to your main property?

What distances are we talking from boiler to the other various heating systems...

As has been said it is not rocket science to work out some suitable switching and zoning...

and a few appropriate relays or cont actors could easily prevent any external triggers coming back into the boiler whilst it is off during servicing and maintenance work...

But we would need to know exactly how it is plumbed up at the moment..

possibly the plumber may have messed it up as well by not putting appropriate valve zoning in place first?

 

[sparkingchip]

All you need to do is research S-plan heating systems.

 

[Sidewinder]

Record?

 

[SLIPSHOD & SLAPDASH]

Record?

Nah, 3 months is nothing here.

 

[sparkingchip]

Do you think its working yet?

 

[Badger]

couldnt you put any feeds from the main boiler via armoured cables to each area and no have any power from each premises just a local power supply to the relevant thermostat/controlller fed from boiler supply if that makes sense.

 

[SLIPSHOD & SLAPDASH]

I wouldn't bother thinking about it, 4 months ago & the op has never visited this site since the 1st day.

 

[binky]

shame, i was looking forward to the final solution.

 

[Doc Hudson]

shame, i was looking forward to the final solution.

I do hope not! http://en.wikipedia.org/wiki/Final_Solution

Doc H.