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You mean the cylinder?
 
No the boiler water tank.
I have the hot water cylinder shut off.
Cheers Simon.
 
Thanks Best, it is a red headed valve ,it is in the hw tank area.
One connection to it goes up into the loft, one connection seems to connect to the top of the hw cylinder and the ( a smaller pipe) goes to the hot water tap in the bathroom sink???
I may be wrong but that's what it looks like.
I've done some more tests and with the valve open the boiler gets up to temp then cycles often at about 70 degrees according to the boilerstat.
When I fully close it the boiler tank temp hits 95 degrees but does not short cycle.
Any ideas??
Cheers
Craig
If I turn the valve shut the boiler tank temp gets up to 90 degrees

My reading of the above may appear crazy (not aimed at you Craig) is it possible that the hot water supply to the sink is being taken from the heating circuit?

Without a few photos or preferably standing in front of the installation I can't figure out if the gate valve is meant to be restricting the expansion from the heating or the cylinder (both no no's).

Craig would you mind uploading a few photos?
 
Hiya Pete,
There is another red tap (call that one no. 1) on another pipe near the hw tank near the red tap we are on about (call this one no.2).
If I turn no.1 tap on then the hw tank heats up on the ch and hw setting on the programmer as well as the rads .
If I put the ch and hw setting on the programmer and close the red tap (no. 1)then the heating is on but the tank does not heat.
This tap is on a pipe which connects directly to the top of the hot water cylinder and then goes to multiple junctions ?
If I put the programmer to hw only the the rads don't heat but the boiler gets to temp before the hwc is at temp.
Please tell me what area of pics you need and I'll put them up (with instructions)
Thanks again
Craig
 
If it helps pete..................
We only ever had hot water from the taps when the I turn on the no.1 tap (from the cylinder).
When I crack open the no.2 valve a bit we get warm water out of the bathroom tap (not hot)
 
best advice is just get a decent engineer in to look at your system, no one has any idea what valve does what unless you can see or trace them back so
giving advice like this is pointless.
 
Much better the two valves are serving different purposes, I have to agree with lame plumber the best advice will be from the person standing in front of the system, turning on and off valves will never prove to be a safe efficient way to control your heating system.

Heating controls play a big a part in the efficiency and comfort levels that can be achieved from any boiler, a big advantage is anything you do now can be part of a full upgrade of your heating system so no money is wasted.

There are good engineers out there you were unlucky with the last one doesn't mean we are all the same, best to ensure the next one is a heating contractor who does more than just service boilers, sadly the trade is being broken up into different segments specialising in parts of the overall trade.
 
Failing that you can always let the tyres down, that will stop the boiler cycling.

Just a bit of levity, pictures or professional me thinks.
 
I've cracked the mystery tap open a fraction and the boiler comes up to temp and doesn't keep cycling on and off. The boiler retains it's heat rather than plummeting as it did when the valve was wide open.
Must be a crude way to control the return temp.
Anyway as suggested I'll leave it alone till someone who knows what there doing has a look.
While i'm here............
I am trying to balance the rads (safe for me to attempt???)
I have followed instructions and have managed to get somewhere near a ten degree drop.
To get this drop on some of the rads the lockshield is barely cracked open , does that sound normal??
Ta,
 
Hi Craig,

The purpose behind balancing the radiators is to ensure an even distribution of the heat around the system, it is not unusual for the rads nearest the boiler to be hotter than the rads at the end of the circuit, by closing the valve you push the heat to the next radiator, this process is only needed if you have some cooler normal rads on the system.

It is safe as the worst you can do is switch off the radiators the fun part may be getting them back to where they were, to make it easier use your notepad and pen, count the turns it takes to close the valve, make a note of it and open the valve up to say within one turn of the original position, if the heat drops too much open it back to where it was.

One of the best ways to regulate the heat in each room would be to discuss fitting thermostatic radiator valves with your engineer when he arrives.
 
First off I agree with what some have said here, despite what mechanical engineering experience you might have setting up these burners to run smoothly, effectively, efficiently and safely requires someone fully qualified and experienced, by no means should they be tinkered with by someone half educated, regardless of how basic the concept appears to them.

All boilers require regular servicing and maintaining if there to run efficiently and safely, and on older boilers like that they should really be serviced every six months.
Efficiency is roughly 8% less to every 3mm of soot build up (you do the math)
With regards to the nozzle, like some have said reducing it's size is not going to make a difference. With the size of your system a .6 gallons an hour sounds about right but any professional engineer would be looking at the boiler manufacturers booklet (and if you don't have it then download it) and then checking the required size nozzle and settings for the burner for power output your boiler requires. These burners have to be set up accurately or you will have problems.

With regards to the cycling it could be a few things.
Starting With boiler:
. Any soot at bottom of flue indicates a flue problem, you could have a partially blocked flue retaining more heat within the boiler (servicing every two years means thats a strong possibility). Flue gases would eventually escape up the flue, the temperature would fall and the boiler ignites again.
.A faulty boiler stat is just as likely, set to cut power to burner when 60-65 degrees C is reached but is cutting out at 50 for example.
. It has been colder recently and when colder air is forced in for the combution process sometimes the flame is brighter and might burn a little hotter.
It doesn't sound like a problem with the burner because I would expect lockout, certainly not coming on and off every 3 minutes.
Inside house causes:
. An old pump on its last legs could be struggling to pump the heat away from the boiler quick enough.
. Air locks or partial air locks can cause the same problem, much like a system filled with black iron oxide (sludge) would as well, when the pump is circulating it will act as a magnet and suck in any sludge causing a restiction in flow and in turn heat away from the boiler.

Those are what spring to mind initially but like I and others have said these things are NOT toys and only someone who understands these things 110% and then some should be working on them.
 
Thanks guys,
An engineer called today to check out the boiler.
All good at that end thankfully.
Things mentioned.....
The 2 red taps ............
1 shuts off the feed to all the hot water taps, so told to leave open.
The other stops the hw tank heating, so told to leave open.
On my system I'm told the hw tank has to heat up whether you want hot water or not.
It all works fine but the boiler still cycles every few mins.
The chap suggested a cylinder stat may help.
when I switch the programmer to ch it shows ch and hw.
The rads get hot and the tank gets hot at the top half.
Am I right in thinking that the coil is in the bottom (cold) part of the tank and cooling the return temps so the boiler comes on again even when the rads are hot enough??
In light of this where on the tank should the stat be fitted?
At the moment the temp of the water in the actual boiler is dropping 12 degrees c in 3 mins after it switches off which seems a lot even in an old house, and cycling the boiler.
Cheers
Craig
 
Hi.

This is just to enlighten you a little on your system but you must call an engineer out to undertake any remideal work.

1.You should have 1 gate valve (red tap) on the cold fill from the hot water header tank to the hot water cylinder, this is to isolate the cylinder should it ever need to be drained down. There should never be any sort of gate valve on the heating circuit that will block off the vent for safety reasons.
2. From what you have just said your system is an old gravity hot water and pumped central heating, camrays were a thing from 20-30 years ago at a time when most systems were like yours. The boiler cycling is because of that sort of system, it always happens as long as the programmer is calling for hot water and when the programmer is calling for CH you will see the HW light on as well, thats how those systems are wired.
This can only be fixed by either having an engineer install the correct zone valve on the hot water return from coil with a cylinder stat to prevent boiler cycling or converting to a fully pumped system with thermostatic contol (which is what it should be)

When you take into consideration the age of your boiler and the fact that at best I wouldn't expect any more than 80-85% Net efficiency I strongly suggest you think about a complete system upgrade.

I've enlightened you on the cause of your issue so now is the time to contact a compitent engineer and discuss what your going to do. All I've said here is to inform you of the issue, I am not advising or suggesting you carry out any work yourself.
 
Thanks for taking the time to explain my system SJB6.
There is no way I can afford a whole new system in the next couple of years unfortunately.
Would you mind answering a couple of questions for me?
Does a fully pumped system mean the system would then be more pressurized?
I have been told that while my system is and old design as you mentioned it was quite a safe system with regards to pressure?
The reason I'm asking is that as I can't afford a new system I was wondering if going the fully pumped route would be massively more expensive than adding a zone valve and a tank stat.
I was kind of hoping I could get the guy back who checked out my boiler to put a tank stat on and the zone valve you mentioned as it sounds cheaper than going fully pumped, and would at least be an improvement would it not??
Cheers
Craig
 
Hi.

Converting to a fully pumped system means that both heating and hot water would be pumped, as it stands your heating is pumped and your hot water is gravity. When they are both fully pumped they would be thermostatically controlled, meaning once desired temperature is reached the boiler would shut down, preventing any cycling, which you have now. With regards to pressure your system is safe now just not thermostatically controlled, when pumps are used they do cause a slight incease in pressure but nothing to worry about, it's just the pump forcing heated water around the system.
Converting to fully pumped will be more expensive than just zone valve and stat because more wiring will be needed as well as pipework will need to be re-done so not to block off safety vent and/or get air entraitment (sludge).
Personally I think you should have a good engineer install the zone valve and stat now, that would atleast give you thermostatic control and prevent boiler cycling (won't improve boiler Net efficiency, just decrease the amount of fuel your boiler burns), then when you can afford an upgraded system (new boiler, oil tank, fully pumped heating system with thermostatic control etc) consult with a good engineer then (look into government boiler replacement schemes, you might find something your eligable for)

Side note : There are open vented and sealed boiler systems, both with their advantages and disadvantages, ask your engineer to explain further.
 
Hi Craig,

Earlier you described your home, many call such properties "Money Pits" yet they love living in them and see each little job as the major step forward that it very often can be.

Well it's time to look on your heating system in a similar way, I suggest that you look at the system and begin upgrading in manageable steps, you need:

An up to date efficient boiler, (though not really the answer when your system is not efficient).

Possibly an upgrade to a well insulated hot water cylinder that may need to be bigger to meet the needs of your family.

I would start with heating zones and controls, depending on the house layout say upstairs, downstairs and hot water.

TRV's on the radiators to give you some control over the room temperatures.

Earlier I asked you what was calling for the heat to cause your boiler to cycle, from what you tell us it appears to be the cylinder;

Get a few quotes for the installation of proper heating controls, you can break up that job in two parts, zones and trv's.

Next step can be either the cylinder or the boiler whichever is the greatest need.

Maybe upgrade the radiators if needed.

No money is being wasted, each step brings you nearer to a decent efficient system.
 
Thanks very much SJB6 and peteheat.
You both seem to be suggesting similar solutions and I am extremely pleased with the advice.
I have contacted the engineer and hopefully he can fit a tank stat and zone valve later next week.
That really is all I can afford at the moment.
Whilst I save up I'll keep tackling the jobs I can do. there are still loads of drafts to sort, the front door is like a wind tunnel etc........
SJB6's description of my system seems to be spot on.
2 tanks in the loft, a vent pipe etc...
The hw tank was installed yonks before I moved in and the bathroom walls built around it. It has no insulation whatsoever . I can reach in the cupboard and cover the top with towels but until I rip the wall down that's all I can do with that.
I wonder how much heat I am losing from an unlagged tank heating water I don't really need??
At the minute I will have to cope with the boiler inefficiency.
Whilst old it does chuck some heat out of the rads no problem now I've stopped fiddling with it. I think my cruddy old house ( never mind the unlagged tank) loses the heat rather than the boiler not providing enough if that makes sense??
If a cylinder stat/zone valve stops the cycling I will be over the moon.
I've timed it and once up to temp the on times are about the same as the off times, so about 1.5 litres an hour by my dodgy maths. Thats nearly a pound an hour!
Anyway thanks again.
Cheers
Craig
 
Thanks for the recognition.

You've done the right thing by getting your engineer out, as informed as you seem only a compitent engineer who's experienced these things 100's of times should touch them.

The stat will prevent the cycling, how much less fuel the boiler uses you'll have to check yourself over a few weeks. You can go and buy a water jacket for your cylinder which will provide some insulation, there not amazing but even if you only save pence thats better than nothing.

Like peteheat said upgrades as and when you can will help as well but without wanting to alarm you when a new boiler is installed or an old one replaced current building regulations must be met and from the age of your system I'm willing to bet the oil tank and oil supply will need replacing as well as the rest of the system (which we've already pointed out)

Also like you said a poorly insulated house is not going to help regardless of how efficient systems are.

Good luck.
 
Thanks SJB6/peteheat.
I will follow your advice.
Your help has been excellent and has pointed me in the right course of action.
Some of the other posts from people were less than helpfull tbh.
I will let you know about if the cycling issue and the fuel useage.
Many thanks
Craig
 
Thanks SJB6/peteheat.
I will follow your advice.
Your help has been excellent and has pointed me in the right course of action.
Some of the other posts from people were less than helpfull tbh.
I will let you know about if the cycling issue and the fuel useage.
Many thanks
Craig

Those would be the ones telling you to stop tinkering with the boiler before you killed yourself or your family?
 
Aaahhh SimonG, I see you didn't get the thinly veiled suggestion I have made?
I am very grateful to peteheat and SJB6 for their reasoned suggestions.
Not only do I understand my system better and how to go forward I now know what my limitations are on my heating system with regard to my personal skills.
I seriously think I could carry out the work needed but peteheat and SBJ6 have persuaded my otherwise.
I don't know your reason for being on this forum SimonG but if it is to persuade people to get professional help rather than 'tinker' you really are going about it the wrong way.
Cheers
Craig
 
Aaahhh SimonG, I see you didn't get the thinly veiled suggestion I have made?
I am very grateful to peteheat and SJB6 for their reasoned suggestions.
Not only do I understand my system better and how to go forward I now know what my limitations are on my heating system with regard to my personal skills.
I seriously think I could carry out the work needed but peteheat and SBJ6 have persuaded my otherwise.
I don't know your reason for being on this forum SimonG but if it is to persuade people to get professional help rather than 'tinker' you really are going about it the wrong way.
Cheers
Craig

Craig, Craig, Craig, you crack me up, you really do. I just hope your engineering skills are better than your comedy skills.

It's a simple statement.

'People who are not competent to work on things, shouldn't'

Do you need it in smaller words?
 
sometimes if people dont hear or read what they want to hear or read they call us unhelpful. Sorry we cant always help but I find its normally a case of people just not listening to sensible advice
 
I wonder how much heat I am losing from an unlagged tank heating water I don't really need??
Alot is the simple answer, a huge amount. Wrap an old duvet round and over it or buy a cylinder jacket from a merchant, ebay, screwfix etc.
 
Thanks Bunker, I've managed to wrap a single duvet round it which should help a bit till I knock the wall down!!
 
Will do SJB6.
There are no electrics of any description on the tank.
There are about 2 foot below the tank so will make sure all is out of the way duvet wise!!
I think the best I can do at the minute is bust the wall down and get an insulated tank in at the same time the dude does the zone valve and tankstat.
I can't see any point getting a tank stat fiitted with no insulation...........?
 
The tank stat will prevent the cycling (better known to me as short cycling). As it stands, say your programmer is timed from 6am to 8am for hot water, the water is up to temperature by 6.30-6.45, that means until 8am the boiler is just cycling through boiler stat, it has no thermostatic control. The stat will effectively mean your not burning that excess fuel you would of been for that hour or so, any insulation on the cylinder will further reduce heat loss.
 
Hi SBJ6.
Getting the zone valve and tankstat fitted later next week.
I 'think' i know what you mean.
Do you mean the heat from the tank to the tankstat will stay stay hotter (than the boiler) and refuse to switch the boiler on............. (no cycling)
rather than the rapid heat loss from the actuall boiler water (and stat) (cycling)
Thanks
Craig
 
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