heating system

[i=p/u]

yo/hi/hello.. i am currently involved in an extension being built to a house. i was giving the drawings to price and all was told about was lights, socket outlets, shower lights/fans ..

now i have been up a few times already disconnecting heating and reconnecting temporary as boiler was moved too different location. few hours, half a roll of 1.5 i can live with.

on speacking to the plumber he says the new extension has underfloor heating and 3 radiators in the single bedroom above which this lady may plan to rent out. so this will require a switch/timeclock to activate heating/ now he says if we have one supply comming from original part of house and one comming from new extension, if one was turned on and not the other, would this backfeed.. ?

so anyway he said if i run a 7core flex from existin part of house this should allow for 3 valves plus run the pump and boiler, what csa would this 7core flex need to be? 1.5mm?

sorry never done heating systems before and more importantly i didnt allow for them.. any help im upfor it and dont say the guys in the white coats, not nice.

 

[i=p/u]

so not thinking about it to much, the extension needs to come on , on its own , underfloor heating and 3 radiators and hot water and the existing building needs to be able to come on , on its own radiators and hot water...

 

[Welchyboy]

If you need the rads and ufh to be controlled individually then the plumber should be running these on their own heating loops/zones , to avoid back feeding the system he should install zone valves to each of these loops and hot water too but this could be generally one for the whole house

Heating can become a little complex to the inexperienced and i would ensure you research what the layout is and what cables you need in place for a first fix, as most of the incorrectly wired heating systems I see are due to a lack of cores for controls

Using .5/.75 flex is fine ( heat resisting) if you can get some detailed info on what's being installed and the lay out I could give you a better idea

Also the builder sounds like he has given you a general allowance to give an initial quote for the job, the additional works you are doing should be billed as extras, but you NEED to clarify you have not priced for these extras at an early stage as if you say nothing then hit him with a big bill at the end, builders no likey!

 

[i=p/u]

cheers, he is on about valves on each of the pipes at boiler hot water, heating, and underfoor heating.. its the cable to the new extension im wondering about.. so from existing postion of time clock il run a 7core .75 flex H/R flex .

in the new extension what would you reccomend to run to future proof this design they after. would you run another 7core H/R flex???

he also on about will need thermostats here and there where do these thermostats run too, isit the boiler or the timclock or valves???? sorry for not knowing to much about this..

 

[sedgy34]

if they have a new supply to the extension it would normally mean a new heating system with its own boiler.
from your post i read 2 supplies to each dwelling and 1 boiler doing all the heating is this correct?

 

[Knobhead]

Napoleon XIV: 'They're coming to take me away' - YouTube

 

[Welchyboy]

i doubt it will have 2x boilers, it will just be an extension of the existing system
unless its a reasonably large area

Where is the UFH manifold going to be sited? you normally need a 5 core flex from your boiler to the manifold

for your UFH stats, these will all go back to your UFH manifold, you will need to check what UFH system he plans on using as some stats are 2 core, some 4 core and ive even wired up a 24v system which needed Cat5 before so check this previously

where are the valves going to be sited, near the boiler?

i would think that a programmable room stat or a timeswitch and seperate thermostat would be used for the rads, this will be seperate from the UFH, and will need to go back to your boiler/wiring centre/valves

Programmable room stat or programmer - 5 core or 2x 3 core and earth 1mm

standard thermostat - 3core and earth 1mm

 

[i=p/u]

i doubt it will have 2x boilers, it will just be an extension of the existing system
unless its a reasonably large area. you are correct just the one boiler

Where is the UFH manifold going to be sited? you normally need a 5 core flex from your boiler to the manifold. yeah well the plumber said run a 7core flex too boiler and this will allow for 3 valves plus power too pump and boiler, i assume from new 3 channel control or is he sayin from manifold???

for your UFH stats, these will all go back to your UFH manifold, you will need to check what UFH system he plans on using as some stats are 2 core, some 4 core and ive even wired up a 24v system which needed Cat5 before so check this previously

where are the valves going to be sited, near the boiler? yes right beside boiler @ far corner of garden

i would think that a programmable room stat or a timeswitch and seperate thermostat would be used for the rads, this will be seperate from the UFH, and will need to go back to your boiler/wiring centre/valves

Programmable room stat or programmer - 5 core or 2x 3 core and earth 1mm

standard thermostat - 3core and earth 1mm

he also said the pump and boiler will run at same time now as the gravity feed has gone with this addition to system..

so isit like this? from cu to fuesd spur to 3 channel time clock,from 3 channel time clock too pump and boiler with a 7core flex . L-N-E for pump and boiler and a live for each valve and one neutral linked between 3 valves. or does this 7core flex go to manifold??.

all in all guys im interested in this stuff, but shouldnt the plumber be tellin me where he wants cables and what type and in you expierience id say he sorts all channel prorammers and switches and stats as its his system???

 

[Dan the spark]

Let him supply all the stats etc as this comes with the kit. Get him to get u a wiring center, u can make you own just a strip of 10 connector blocks in an enclosure. With the bits of kit he supplies should come wiring diagrams, ask him what system it is ie s-plan or y-plan and just terminate the cores of the parts to the correct numbers on the connector blocks

 

[Dan the spark]

Do u know what make the ufh is?

 

[i=p/u]

sorry dont know what system, just know its water fed . he mentions 3 channel time clock and get the cable in 7 core flex... i will find out more in due course. the bricky's are just in now and we reckon the roof will be on by 16th may.. i never priced for any heating so will have to speak to builder.. let him sort it. if he wants a socket , in a jiffy haha.

 

[i=p/u]

does the wiring system normally be beside manifold or timeclock programmer

 

[Dan the spark]

The wiring center is normally sited by all the 2port/3port valves as these come pre flexed up, which are normally in an airing cupboard of sorts. U will get a control/wiring ceter for the ufh too which needs to be mounted near the manifold as the actuator vales will go to here and so will you room stats for the ufh. It's quite hard to explain over the net without confusing u more really. If u go to the Honeywell website and look at their different wiring diagrams this might give u a little bit of info, it's all just switches at the end of the day really

 

[Dan the spark]

Last one I done went like this
-3core from spur to hw/rads wiring center in cupboard LNE
-6cores from hw/rad wiring centre to ufh wiring centre LNE and then the other 4cores for switching the boiler/pump and ur time clock channel
-6cores from hw/rads wing centre to time clock LNE and 3channels
3-core from hw/rads wiring centre to rad room stat(5core to be safe)
5core from hw/rads wiring centre to boiler(some boilers only require 3cores as pump is incorporated and runs with boiler depends on make and type)

From ufh wiring centre
3 core to each room stat, some stats have set back feature which needs 5cores
and there will also be a pump on here which is just a flex and a zone valve which will be pre wide and connect into the ufh wiring centre

Obviously the one ur installing could be different to this none and others may have a bit more input, I haven't done a great deal of these

 

[Welchyboy]

as said above the best thing to do is look at the wiring diagram supplied with the UFH kit, this should tell you stat cables needed etc

The rads and hot water will be a seperate system (but all supplied from the same spur, dont use two electrical supplies, and remember 3A fuse MAX dont leave the 13A one in the FCU!)

imagine them as two independant systems, just both using the boiler to supply them with hot water, follow the supplied wiring diagram for the UFH

Then look up S-PLAN wiring diagram, this is what you will need to follow for your rads and hot water

unfortuanatly its a more than average system for sombody who hasnt done much heating before

thing is nearly all heating systems have slightly different variations and set ups to another and without being able to see it its hard to give definite answers

the first few i done were a bit of brain ache but once you get your head around them its really quite simple