What Central heating system is this?

[Crosswire]

Ok ,

I've got underfloor heating with 4 zones, one programmable timer, gas boiler Vailliant Ecotech, Megaflow cylinder in loft, 4 (I think) thermostats and a pump. Which central heating plan is this please?

 

[Guest123]

Sounds like an "S" plan with the heating zone valve operated by the UFH manifold as opposed to a normal roomstat.

 

[Crosswire]

Thanks lenny. I've downloaded all the wiring diagrams, but where can I learn more abot different types of central heating plans? All ideas welcome .

 

[antimatter]

HERE

http://www.honeywelluk.com/lib/pdf/Wiring-Guide-Issue-14.pdf

 

[madrid]

are you sure the stats are not programmable stats.sometimes they are battery operated and you only have a feed and switchwire at the stat.if its underfloor heating there should be a wiring centre with all the control electronics in it for the underfloor(all the cables for the heating should go back to it) and a single channel programmer for the hot water.

 

[Graeme Harrold]

Very handy reference guide that and covers 99% of systems. Be aware that some of the newer boilers now have the pump controls inbuilt. Ive just had a Worcester fitted at home (wired the S plan myself) and the pump is wired from the boiler rather than the wiring centre..........

 

[ian]

does the boiler have rads as well as Uf heating?

ian

 

[Crosswire]

@antimatter : nice link , thanks very much

@madrid : stats are standard room stats, not programmable but are still in boxes - see below

@ian : no rads anywhere , only form of heating is underfloor


I feel a bit of background is required here. I have been tasked with completing a job where the original electrician has been thrown off , with the job 90% complete.

He has left the wiring centre a complete jumble of cables, and has not mounted any room stats anywhere. I think the cables for them are hidden in the walls, because there are 4 '3 cores' in the wiring centre, and 4 stats in his materials box. Also the UFH manifold has 4 pipes on it.

Not really sure what he has done, so am having to try and work it out as I go, and am starting to panic cos weather is starting to get cold, and client will want heat soon.

What I should have mentioned earlier is that there seems to be a seperate UFH for the top two floors of the house, with the manifold located next to the immersion tank.

I don't understand why the boiler on the ground floor (ecotech vailliant) and the immersion in the loft are BOTH required - surely the boiler can do both hot water and heating?

Or are they two seperate systems ? One for ground and one for top floors? Please help , thanks .

 

[Guest123]

The immersion is more than likely there just as a back up should the boiler fail.

If it is an "S" plan there should be seperate zone valves, 1 for HW and one for CH, there may even be a 3rd valve as you say there is an additional manifold for the top floors.

How many channel is the programmer a minimum of 2 but again possibly 3. You also say the manifold has 4 pipes at it??? this is a bit confusing as normally flow and return is either tee'd in or ended here....is there a pump at each manifold also???

 

[Graeme Harrold]

For UFH, there may be mant more zone valves, potentially 1 per room. you will also hav floor sensors to monitor the floor temp in addition to room stats. Me thinks you have more homework to do. A good idea would be to photograph the various bits and post them back here............

 

[Jay Sparks]

Thanks lenny. I've downloaded all the wiring diagrams, but where can I learn more abot different types of central heating plans? All ideas welcome .

Im actually doing a one day course in october run by honeywell telling you all about s & y plan boilers and how to install them and fault find. It cost £30 quid and you get your dinner and a cert to say youve done a honeywell accredited boiler install course. Give them a bell and see if there running one near you. Gotta be worth £30 quid and a day of your time!

Jay

 

[madrid]

I,ve done a couple underfloor systems in the last couple of years.I have found that the system components are usually purchased from one of the many specialist companies that now make these systems ,these companies usually design the system for the customer and all materials are supplied in a pack including wiring diagrams and instructions .I would suggest you ask the customer where he got the system and phone them up.tech help is usually pretty good.The ones I have done all had programmable stats and a motorised valve for each manifold .roughly 4 zones to each manifold.just needed a spur supplying the wiring centre for each manifold and everything went back to it.The last one i did had two manifolds supplying 8 zones downstairs and an s plan for the upstairs rads and the hot water.

 

[ian]

I will make an assumption there is a manual manifold with each zone controlled by a regulator on the top of the manifold. I will also make the assumption that it’s a conventional manifold rather that a ZRU.

I think you will have 2-channel controller one channel for DHW and the other for UFH.

Looking at the UFH, its simple, any one of the UFH stats will initiate the zone valve to UFH and once in the correct position start the pump and fire the boiler, once the water is flowing to the manifold the individual zone regulators on the manifold will either allow water to pass into the appropriate zone or not.

Basically it’s a modified Y plan.

If you check the plumbing, there should be only one mid position valve, however, if there are two single port valves, let me know because its slightly different.

Hope that helps.
Ian

 

[Crosswire]

The immersion is more than likely there just as a back up should the boiler fail.

If it is an "S" plan there should be seperate zone valves, 1 for HW and one for CH, there may even be a 3rd valve as you say there is an additional manifold for the top floors.

How many channel is the programmer a minimum of 2 but again possibly 3. You also say the manifold has 4 pipes at it??? this is a bit confusing as normally flow and return is either tee'd in or ended here....is there a pump at each manifold also???

yes there is a pump at each manifold, each of the UFH pipes has a 4 core cable (brown ,blue, black ,grey) attached to at the top. Also there seems to be seperate wiring centres and programmers for the downstairs boiler , and the loft immersion .

 

[Crosswire]

Im actually doing a one day course in october run by honeywell telling you all about s & y plan boilers and how to install them and fault find. It cost £30 quid and you get your dinner and a cert to say youve done a honeywell accredited boiler install course. Give them a bell and see if there running one near you. Gotta be worth £30 quid and a day of your time!

Jay

definitely sounds like a good idea ! (and dinner included , sweet!) cheers

 

[Crosswire]

I will make an assumption there is a manual manifold with each zone controlled by a regulator on the top of the manifold. I will also make the assumption that it’s a conventional manifold rather that a ZRU.

I think you will have 2-channel controller one channel for DHW and the other for UFH.

Looking at the UFH, its simple, any one of the UFH stats will initiate the zone valve to UFH and once in the correct position start the pump and fire the boiler, once the water is flowing to the manifold the individual zone regulators on the manifold will either allow water to pass into the appropriate zone or not.

Basically it’s a modified Y plan.

If you check the plumbing, there should be only one mid position valve, however, if there are two single port valves, let me know because its slightly different.

Hope that helps.
Ian

Ok the plumber is coming on Wednesday to fix a leak, so I will pick his brains as to what he installed, (if I can take the shame of asking a plumber for help). Took photos but couldn't upload cos size was too big

Thanks for all the help and will report back with results

 

[Guest123]

Mmmm, tough one to advise on this mate as it seems to be a collection of seperate parts to complete the system.

Without being there and seeing it myself pumps, valves, stats etc, the most I could offer is an educated guess.

You may need some additional relays to avoid backfeeding, or perhaps the control centres have these built in. Hard to say.

 

[Crosswire]

Yeah was originally installed by Polish sparky who refused to finish job unless the client paid him more money, over and above the price!
Needless to say he was elbowed and I got lumbered with it Ho-hum such is life....

 

[ian]

Yep I agree with others, its difficult to say. The 4 wires from the manifold valve actuator head are the live & neutral. (The live will be the switch wire from the appropriate stat), the grey and black will be across a contact, which will, these will drive a valve, start the pump and fire the boiler, but without seeing it it’s difficult to say. You may need a relay to 2, depends how it’s plumbed.
Finally, it sounds like there are electrically operated actuator head installed on the manifolds, if so the some of info I gave you above is inaccurate, sorry I should never make assumptions.
Also ask the plumber if he has fitted a diverter valve (2 cores & earth) a mid position valve (4 cores and earth) or a zone valve (5 cores and earth)

 

[ringer]

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