How would you do it???

[Oracle]

Hi all,

I have been asked to wire a central heating system (y Plan)... simple enough.. but...

Its one boiler, with one 3 port.... this is where it starts to get interesting...

2 controllers/programmers and two room stats.

Basically it one two separate accomodations fed by one boiler.

The central heating circuit out of the 3 port, will split into two zone valves, one for each place.

The HW obviously won't be zone, one cylinder stat

How would you guys suggest wiring this ( with 2 controllers and rooms stats), with the CH output from each controller also opening the zone valve

The pump will be connected to the boiler (to provide over run).

Just gotta watchout for conflicts between the controllers/valve

O.

ps - I have my way of doing (don't ya love DIN rail boxes with twin relays)

 

[Northern Electric]

This is a very interesting one, though who pays for the gas used to heat the water, or will it be a shared bill?

I would say the CH side of the prog would feed through the room stat as usual then pull the zone valve in for each respective property.

The Hot water side of the 3 way valve would need to be controlled independently for each property, as you say 2 seperate 240v relays pulling in to power the valve, I would probably choose to wire the 2 relays through each other so you didn't have 2 independant supplies on the valve terminals at once.

This is just a quick theoretical answer, obviously I don't know the actual job.

Am I going down the right path?

What's your theory on powering the boiler?

 

[anwah]

Dont bother with the Y plan. wire it on an S plan ie 1 valve for DHW and 1 for CH

Then wire the same for the other part of the property.

 

[batty]

Sounds a hard one to do to me. If I had to do it I would ring Honeywell technical a get them to send you a wiring plan or who evers controls they are they should be able to do it for you. some of the other more experienced sparks may know but this is beyond me.

Batty

 

[Evans Electric]

This could be interesting. !!! I have to say that these days, (assuming the Heating Engineers are hiring you) , I would say get an expert to conjure up a wiring diagram and I'll come and do it . Main reason being if you cock up and something like the fan assisted flue doesn't operate from one flat or boiler doesn't overrun from other flat , bill for ******** boiler on your desk. Plus what are you charging to design it.

I did one years ago, bloke wanted various zone valves/stats etc. ended up with relays and connection boxes everywhere, best part , heating blokes had sodded off and left me to it , didn't even know what system it was.

Non standard stuff so spent forever working out how to do it ..bloke didn't want to pay for the time spent once it was working .

Deke

 

[Evans Electric]

Just read Batts post, thats the way to go.

Deke

 

[Andy™]

should be simple. i have done something similar with the combi in my house - output of CH feeds a 3 port, which split between house heating and conservatory heating. its wired like a fully pumped 3 valve, with 'DHW' side of valve to conservatory, and CH side to house. the signal to start boiler is connected via the room stat terminals. still got a perm live for the hot water. although its done with a 2 channel programmer, it wouldnt be too much extra to use 2x 1 channel for each place

ill get some pics of the setup later if you want?

obviously though, splitting gas bill could be quite a challenge!

if your still stuck, let me know the boiler make/model and ill make a wiring diagram for you

 

[mikep]

I'd just stick 3 zone valves from the boiler all three zone valve switches wired in parallel to control boiler /pump, zone 1 hot water programmer controlling hot water via cyl stat, then a programmable room stat from dwellings controlling zone valve 2 and 3 respectively.

Nice and simple.

Mike

 

[batty]

I would be careful that you have two accomadations fed from two supplys. Does each accomadation have its own meter and consumer unit or are they all from one meter and consumer unit.

 

[Andy™]

the who setup would need to be from one supply, or you will have problems with isolation etc

 

[mikep]

As they are sharing the gas I don't think a few watts of power from one dwelling is anything to worry about , all seems quite cosy in those 2 households ??

 

[NozSpark]

Idealy I go for 3 x 2 port vavles,

but if you have to keep the set up then use the controllers/room stats to control the 2 ports and the demand output from the 2 ports to the heating input for the 3 port.. demand out from the 3 port to boiler..

I think that should work

 

[kme]

I must admit to liking Anwah`s idea

However, if we are to stick with the O/P scenario, I`d design it "on the fly".

The boiler make & configuration doesn`t really matter - all it wants is a "burn" control signal

Flue fanning etc. doesn`t come into your remit - the boiler handles all of that, internally.

wire each property up as *seperate units*, in case they ever have their own boilers; then just have a "box of tricks" at the interface point, which is where the din rail relays`ll come in handy. The logic path isn`t too difficult.....

n.b. I`ll do it, if no-one else will

KME

 

[SPECIAL LOCATION]

I must admit to liking Anwah`s idea However, if we are to stick with the O/P scenario, I`d design it "on the fly".

The boiler make & configuration doesn`t really matter - all it wants is a "burn" control signal

Flue fanning etc. doesn`t come into your remit - the boiler handles all of that, internally.

wire each property up as *seperate units*, in case they ever have their own boilers; then just have a "box of tricks" at the interface point, which is where the din rail relays`ll come in handy. The logic path isn`t too difficult.....

n.b. I`ll do it, if no-one else will

KME

I would concur with old beer headGuiness DrinkGuiness Drink... :x

Personally I think heating controls can appear a bit of a "dark magic" and "mystery" to some people because some of the switches just happen to have, Timers, Thermostats or Motorised valves joined to them!

BUT... in simplistic view ALL you are doing is taking a live "please a switch the boiler on" signal via a series of switches that are either opening or closing to enable or disable to boiler signal...

e.g.

Step1:

Fuse spur live feed.

Step2:

From Step1 through a Timer switch (maybe with manual boost/override/off feature)

[Makes 'ON' contact to pass voltage to next step]

[breaks 'OFF' when you want to turn boiler permanently off]

Step3:

From step2 through a thermostat switch (maybe room or tank thermostat)

[Makes 'ON' contact if environment{water or room} is too cold]

[breaks 'OFF' if temperature reached]

Step4:

From step 3 to operate a motorised valve (opens up water flow to specific area of pipework)

[When motorised valve has travelled fully open an integral micro switch is operated

this "Makes ON" between Orange & Grey conductors of valve]

[use these orange & grey to switch a live supply to boiler & pump to fire up & get the water shooting!]

Grey is normally a perm Live supply,

Orange goes to Boiler & pump!

So in a nutshell its three switches effectively operating in series with each other!

with a bunch of neutrals & earths common-ed up from each of the stages!

Then you just multiple the above set up for as many zones as you want to have!

I have a customer just up the road from me with a large property...

Upstairs heating.

Downstairs heating

Water cylinder

which is in essence what the op wants to do...!

 

[kme]

Ta bud.

In fact, thinking about it now, I`d probably disregard the 3 port, have tees in flow/return pipework, and use 2X 2 port valves in each property. Each valve fed from its relevant timeswitch / stat, and all sense lines returning to boiler feed. It doesn`t get any easier than that

 

[kme]

Hi all,The HW obviously won't be zone, one cylinder stat

EH! Is this, like there`s 1 hot tank feeding both properties?

if so, 1 property only needs a CH supply, and 1 X 2 port valve

 

[tom1]

I would concur with old beer headGuiness DrinkGuiness Drink... :x Personally I think heating controls can appear a bit of a "dark magic" and "mystery" to some people because some of the switches just happen to have, Timers, Thermostats or Motorised valves joined to them!

BUT... in simplistic view ALL you are doing is taking a live "please a switch the boiler on" signal via a series of switches that are either opening or closing to enable or disable to boiler signal...

e.g.

Step1:

Fuse spur live feed.

Step2:

From Step1 through a Timer switch (maybe with manual boost/override/off feature)

[Makes 'ON' contact to pass voltage to next step]

[breaks 'OFF' when you want to turn boiler permanently off]

Step3:

From step2 through a thermostat switch (maybe room or tank thermostat)

[Makes 'ON' contact if environment{water or room} is too cold]

[breaks 'OFF' if temperature reached]

Step4:

From step 3 to operate a motorised valve (opens up water flow to specific area of pipework)

[When motorised valve has travelled fully open an integral micro switch is operated

this "Makes ON" between Orange & Grey conductors of valve]

[use these orange & grey to switch a live supply to boiler & pump to fire up & get the water shooting!]

Grey is normally a perm Live supply,

Orange goes to Boiler & pump!

So in a nutshell its three switches effectively operating in series with each other!

with a bunch of neutrals & earths common-ed up from each of the stages!

Then you just multiple the above set up for as many zones as you want to have!

I have a customer just up the road from me with a large property...

Upstairs heating.

Downstairs heating

Water cylinder

which is in essence what the op wants to do...!

he back, the late night scholar

 

[SPECIAL LOCATION]

EH! Is this, like there`s 1 hot tank feeding both properties?if so, 1 property only needs a CH supply, and 1 X 2 port valve

Well this is wot I woz just a ponderingificus!!!!!!

If a Combi boiler... Nowt needed water comes on when run tap...

If hot cylinder...

Just use a tank stat to keep tank hot all the time...

because you never know when either of the properties will need hot water..

so just keep the ****** hot ready to roll!!!

then only need 2 x heating circuits rad water & lectrwicksBlushing

 

[SPECIAL LOCATION]

he back, the late night scholar

The bad news is I am following you Tom1] ....

Don't turn around or look over your shoulder.....

HALLOWEEN is approaching & you may get a shock!!!! ] ] ]

YES...

I AM THAT UGLY!!!!!

:^O :^OROTFWLROTFWLROTFWL

Guiness DrinkGuiness Drink

 

[tom1]

will u have both hands on my shoulders when i get this shock:_|