problems wiring a boiler

23 Oct 2004
Reaction score
United Kingdom
Evening all,
i am experiencing problems with wiring a boiler. it is a wickes halstead 60. it is gravity HW and PUMPED CH.
it has one 2 way zone valve on the central heating. No cylinder or room stat,customer doesnt want one his old boiler didint have one so he cant see why he needs one now. The instructions dont cover this scenario.So have been racking my brains trying to sort it and think im nearly there
Where the room stat should go is connected to the CH ON in the programmer,number 4 on tag strip. Cylinder stat should go into 6 and onto a zone valve and then to 10 to boiler.
My problem is now where do i connect the HW ON from the programmer , i think it should be to 10 on tag strip, along with the zone valve for the CH. But that is my problem. Can anyone help.
Sponsored Links
I trust you know the requirements of Building regs with respect to installation/ replacement of boilers?
yep, left him pondering tonight about a thermostat etc, tomorro hoping he will be happy to change without me forcing the issue!!
I think installing a hot water cylinder without a thermostat on the cylinder is dangerous. If the boiler stat fails then as a recent case in the press demonstrates, the water can boil up into the storage cistern in the attic, this softens and ruptures, severe scalding or death results when the water goes through the ceiling.

Gravity systems are inefficient, why not a y plan without room stat or radio room stat. A room stat is best practice of course.

If its gravity hot water plus no room stat, why is there a 2 way zone valve on the CH and how is this operated (a scrooge switch ?).

Tell the guy "it'll only work with appropriate controls, the boilers are made these days so you can't ignore the regs. without enormous trouble, time and hence expense.....Insurers won't tolerate it, etc" and spare yourself the grief.
Sponsored Links
fronnie, the monster may not bite you now, but you never know if, or when, it will be hungry.

Not complying with building regulations is now a criminal offence (I suspect you know this). If the customer moans to corgi (and if he doesn't care about the regs, he certainly won't care about dropping you in it) you won't have another leg to stand on. If something happens, you won't have the other leg to stand on, like no insurance cover. (That's three legs you won't have :D)

Brumylad's get-out may work if the customer isn't too technically aware. You could mention the system will cost more to run without the stats, as the boiler will be going on and off just to keep itself hot even when no other heat is needed. And what controls the pump? This is needed as the boiler will do it's crust not being able to get the heat away, and here brumylad 's point is valid. The other thing you have do abide by, even more than building regs, is the manufacturer's instructions. Not following these means you have ALL the liability.

You'll have enough work without customers like this, unless you want to be a cowboy operator, just walk away from the next one who does this. Be careful not to take on costs which means you can't escape.
The way round it "partially" (on this occasion and to learn a lesson) is to fit a Honeywell C plan, it will come with all the wiring instrtions, I know I know I know, a C plan doesnt fully comply with Part L, but at least it gives a room stat, and a cylinder stat, no building inspector would notice and corgi dont give a stuff on Part L anyway as it isn't gas related, dont forget to make sure you fit your T/valves on the rads in sleeping areas, the boiler should be a peice of piiss to sort out by just looking at the wiring diagram that came with it, if you cant understand it maybe you shouldn't be wiring it, make sure next time that you put in your written "quote" (like the rest of us) to include for fitting to all current regulations, if they dont want it, dont do it, I think at some point in the future a lot of chickens are going to come home to roost, and they wont care where they shiit, be careful out there.
When the boiler stat fails, regardless of type of controls fitted, hot system water will end up in the header tank. Could be a fully loaded installation, and still boiling water will chug into the header tank.
thanks for your replies chaps he phoned this morning and either wants a cylinder and room stat fitting or maybe a combi he will now let me know shortly!!
Let's hope he chooses a combi, that'll teach him :evil:
Mmmmmm, wonder how you wire a combi, bright flashy green and stripey is live, brown soil colour is earth and blue is, errrrr, spare :confused:
I thought you connected the blue to the cold plastic water main, same colour,
fix it with a jubilee clip.
thanks for the replies chap, yet again you have been most helpful to a man in need, very much appreciated. i converted it to fully pumped s plan,cylinder stat and room stat.
wired it in and now the boiler fires independantly of the programmer. got a sparkie coming tomorro to give it the once over and sort me out.
one thing ive learnt is take me time and plan things better.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links