Johnward & VicVapour

[EFLImpudence]

I'm afraid I couldn't get it to work without any switches.

I think it's time for Electrics UK (if I may) to announce that a lot of heating engineers (plumbers ?) are very clever people and their inferiority complex is totally unwarranted.

 

[ecowarrior]

So come on then while I've got your attention, how do we wire up the boiler in the OP that's so complicated only a plumber can do it?

No one said it was complicate or that only plumbers could do it. We have to do it and I just wondered considering the constant gip we get for being carp part time & totally illegal electrically if any of the 2500 people viewing this would hazard at an attempt. It was at the time a Friday night with nothing on the box. This is one of the most viewed threads you have had in ages so it obviously interested many people. If you really want to see it you really welcome - both specifically for the intergas with its clever clogs innards or the more simple ( my original thought) normal A rated boiler with WC.

 

[ecowarrior]

I'm afraid I couldn't get it to work without any switches.

I think it's time for Electrics UK (if I may) to announce that a lot of heating engineers (plumbers ?) are very clever people and their inferiority complex is totally unwarranted.

Is that something nice you are saying? very pleasant. rewarding in fact. Said from the heart. I feel all warm & gooey inside. Thankyou

 

[Bill Stickers]

It may.

It may simply adjust something.

It does not necessarily result in something switching.

Just like a dimmer switch then

Just as your finger isn't a switch yet it can result in a light being switched off.

Only if you operate a switch with your finger

I wish I was as clever as a plumber

 

[EFLImpudence]

considering the constant gip we get for being carp part time & totally illegal electrically

As I said in my fist reply, only those of you who obviously are will get flack.

 

[RF Lighting]

So come on then while I've got your attention, how do we wire up the boiler in the OP that's so complicated only a plumber can do it?

No one said it was complicate or that only plumbers could do it. We have to do it and I just wondered considering the constant gip we get for being carp part time & totally illegal electrically if any of the 2500 people viewing this would hazard at an attempt. It was at the time a Friday night with nothing on the box. This is one of the most viewed threads you have had in ages so it obviously interested many people. If you really want to see it you really welcome - both specifically for the intergas with its clever clogs innards or the more simple ( my original thought) normal A rated boiler with WC.

I get the feeling we've all been playing one-up-man-ship with this thread.

In all honesty, I'd be interested in seeing your wiring diagram. I do wire lots of complicated systems for a local plumber. All we do is have a discussion on site of what bits he has and how he wants them to all work together. I knock up a quick sketch of how it'll be wired. When he's happy I pull in the wires, do all the connections and test everything electrically.

Break it down into a simple flow chart and it's nothing to be scared of.

I did this one recently. Not sure what letter plan you lads would call that?
Boiler heats a big cylinder. This can also be heated by a solid fuel stove when its on.

The cylinder feeds the central heating upstairs, a 10 zone under floor heating system, and eventually another UFH system in a granny flat once that is built.

 

[ecowarrior]

OK no probs give me till just gone 10pm!!

 

[ecowarrior]

A fundamental difference is most of my /our stuff is retrofit. U have a 20+ year old system & u r plonking a hi tech boiler onto it. My policy is to get as much out of it as possible rather than just bang it on the wall.

Some (lots) of the new boilers are looking at new installs adding NTC into cyls that are designed for that. Here we have to use a on off tank stat. To get the 2 temps u can use the WC pins to add a high resistance to kid the boiler its cold outside so it will max out the flow temp whilst the resistor is in place. If u can sort it that the resistor is added when hot water is called - well u have hot water priority and when the hot water is satisfied the heating continues back to whatever type of roomstat is controlling it be it an on off stat with the set temp set by the owner or O/Therm.
Electrically its easier to do this on a Y plan by converting a Y plan 3 port mid position to a 3 port diverter valve by joining White & grey & not using the orange. As long as the boiler has a separate signal for DHW and WC it will work this way. (Some MU like WB dont just add a ntc to the outside wall - that have to add a WC module including the electronics that make it work (con job) so this only works on WC that just needs an external sensor.)

The relay (simple 240V from Maplins) sits inside the boiler bat can go anyplace

Untitled

• ecowarrior
• 12 Mar 2012
• 1

We r lucky with our forum as it closed. Unlike a lot of chest beating that goes on in open forums we suffer very little from that. Everyone seems very helpful no mater what the experience of the poster. We have every single aspect of the gas world represented from agents, BG , meter fitters Industrial, oil, (dare I say sparkies) and plenty clued up IT boys. We have an amazing reference library as well. Most everybody contributes. I am in the throws of doing a 'paper' on NTC's. There is always someone will think of somat you haven't so it all gets covered in the end. The one thing that 99% have in common is plumbing!
Its a shame u cant have one for NIC + elecsa members only.
Perhaps we should have honorary members !

If u ever need to mull over some ideas u should contact some of us as there are plenty who like to mull over circuits and offer suggestions! Plus by the looks of it our drawings are prettier than yours!

 

[Jezclayton]

Is this solution endorsed by Intergas as I’m not sure they would appreciate their logo being utilised otherwise? I suspect I already know the answer to this.

Rather than faff about with relays and resitors bridging the external sensor connections, I would chose a boiler that did the job I wanted, probably an Avanta in this case and wire in a diverter. No point in keeping two old valves for the sake of it.

Regards

 

[ericmark]

Although your plan will work of course my question would by why not use the new tank sensor anyway? The boiler give priority to domestic hot water and a cistern takes a long time to heat up. By interfering with the system you could end up with no heating for an extended period.

BAS does have a point why use a single boiler in first place my house has separate boilers for domestic and central heating and it works well.

To me no one has found an answer on how to use a condensating boiler on a system originally designed for a non condensating boiler and this is the major problem. Myson radiators do not control the flow of water through them they only control when the fan turns on so when heat is not required in that room hot water is returned to the boiler. So once that room is warm the boiler will reduce or stop producing hot water for other radiators in the system.

The same can result using a hot coil to heat domestic water in that once most of the water is hot but still not quite to point where stat will remove demand hot water can be returning to the boiler.

All the motorised valves are open or closed they do not part open with perhaps the exception of mid type but even them it's one of three positions.

I have looked at my Myson many times and tried to work out how it could be used once I change to a condensating boiler and only method it would seem it to fit a motorised valve on the Myson with a small bypass. It seems wrong to have to mess around like that and one would think there would be a modified Myson designed to run with a condensating boiler but to date I can't find one.

However the new boilers it seems will extract the last bit of energy from the gas and convert it to electric rather than using the it for heating which would mean the return temperature of the water would no longer be important like with old boilers. So I am crossing my fingers and hoping my old boiler lasts until these become more common place.

But back to orignal question how to use the boiler you selected in an old system without changing orignal system. I look of course at my own house as a model and still arrive with same answer.

You can't

Some plumbing and electrical alterations will be required these will vary house to house but in most houses something will need to be altered to stop premature return of hot water.

My old hot coil was rather inefficient and to be able to use the modern condensating boiler something would need to be done. Willis or Eberspacher type heat exchangers or Calorifier as Eberspacher call it would need fitting or at least provide some method of cooling the return water more like with a towel rail.

To do this means your not using the orignal system your modifying it in some way so in most systems you still get same answer.

You in the main can't use a condensating boiler with an old system. Even the old radiator valves will not take the pressure of a closed system.

Once you start changing lock shield valves or any other modification to old system then why not continue and change cistern, radiators and any other part which will not work with new system? I can see the point in not ripping out pipes but if some one is going to the expense of a new boiler specially if supported with some form of grant then why would you not also change the cistern to a modern type with an efficient heat exchanger? It would be spoiling the ship for a half penny of tar.

 

[bernardgreen]

What about boilers that measure the return water temperature and if it is too high for condensing the boiler throttles back or modulates ( reduces the flame height or the number of flames ) until the boiler output matches the demand from radiators. Some boilers have a 4 to 1 ratio, mine can provide 16 Kwatts if all radiators are calling or modulate down just over 3 Kwatts if only one tank is calling for heat.

 

[ban-all-sheds]

We r lucky with our forum as it closed.

And you have the gall to complain about false accusations of illegality being levelled against you?

DIY gas work is not illegal, you know.

Unlike a lot of chest beating that goes on in open forums we suffer very little from that. Everyone seems very helpful no mater what the experience of the poster.

Given what goes on in the public forum I find that hard to believe. Factor in the policy of lying to people asking for advice because giving truthful answers is too much like hard work and I find it impossible to believe.

 

[ericmark]

What about boilers that measure the return water temperature and if it is too high for condensing the boiler throttles back or modulates ( reduces the flame height or the number of flames ) until the boiler output matches the demand from radiators. Some boilers have a 4 to 1 ratio, mine can provide 16 Kwatts if all radiators are calling or modulate down just over 3 Kwatts if only one tank is calling for heat.

This is the problem. Old boilers only measured output temperature new ones also measure input temperature and many of the older units return the water too hot so the boiler closes down.

With the Myson the flow was very high and did not change when it was delivering heat to when it was not. With the modern radiator the TRV means it only has flow when cold.

One must assume the old system did not have any TRV's fitted and relied purely on the lock shield valves to regulate heat to each room.

I can't see any way one can use a modern boiler without changing some other items on the system be this a manual valve for a TRV or a thermostat switch for a sensor.

He has not said "I want to retain this one item how do I do it" it was I want to retain it as was and use a new type boiler. That simply will not work.

Once one says OK I will change some items then why would one change to using a TRV and not to using a sensor instead of a switch?

So back to orignal answer is simple in the main it won't work.

 

[oph]

We r lucky with our forum as it closed.

And you have the gall to complain about false accusations of illegality being levelled against you?

DIY gas work is not illegal, you know.

Unlike a lot of chest beating that goes on in open forums we suffer very little from that. Everyone seems very helpful no mater what the experience of the poster.

Given what goes on in the public forum I find that hard to believe. Factor in the policy of lying to people asking for advice because giving truthful answers is too much like hard work and I find it impossible to believe.

No, it int illegal to do DIY gas work but how do you expect people to know if they have a leak?

 

[ricicle]

No, it int illegal to do DIY gas work but how do you expect people to know if they have a leak?

To carry out gas work within the law it must be done safely and competantly which will include carrying out a system pressure test before and after the work.