Ideal Logic Combi 24 no hot water or heat

FataVerde

13-year old Ideal Logic+ 24 (Combi) has regular pressure problems so I regularly top it up. Recently, it's not giving me really hot water, just warm, even though the controls on the boiler are set to maximum for both water and heat.

The other day I stopped getting even warm water and noticed the pressure was too high, between 2 and 3, and the arrow just vibrated there. I bled the radiators and got the pressure back to just above 1. Then reset the boiler and set it in winter mode. The boiler turns on, the burner lights up when I turn on the hot water tap, but in a minute turns off and I get either lukewarm or plain cold water at the bathroom tap, right next to the boiler. The radiators are not heating up either.

The boiler message is "No water flow lockout" (once followed by "No water thermistor", but this disappeared on future resets). Then the boiler cycles though these messages: 1. Fill system to 1 bar; 2. Bleed radiators; 3. Check radiator valves open; 4. Reset boiler; 

What could be the issue? And could anybody check if all the valves are correctly positioned?

Or could this be an issue with the Nest thermostat the previous owners linked to the boiler? I set it to manual and only use the boiler controls.

Or could this be an issue with the nest thermostat with link? The previous owners installed one, but I set it on manual because I just want to use the boiler controls.

ThisIsWeird

Hi FV.
Really, far too many potentially-unrelated issues going on at the same time to even begin trying to diagnose.
You've had regular pressure drops, a pressure soar - these 'could' be simple issues, but still - and a boiler that just doesn't deliver hot water.
Once the pressure is 'ok', as it currently is, then the boiler should work. That it doesn't means there's something else amiss. So, too many 'issues' for me...
I doubt very much it has anything to with the Nest. If the boiler comes on, then it should supply 'hot'.
Perhaps time for a fixed-price repair? These will (should) tackle all the issues, and you'll be surprised at how many parts they are prepared to replace! If course, you may also get the 'beyond economical repair' claim. But, 13 years is not 'old'. Oldish, yes, but shouldn't be at the end of its life. Quite.

ThisIsWeird

The filling loop taps look to be both 'off', which is what you want. Any idea why the pressure went high that time - could you have left them slightly open?
A combi failing to provide neither dhw nor ch suggests a shared issue, so perhaps a sticking diverter valve. That would also fit in with the 'restricted flow' report.
Not a DIY job unless very competent. But, usually a simple replacement task for a GS.
Do you have a trusted local GS? Perhaps worth calling them in the first instance in case it's a simple issue, and I've known them to suggest going elsewhere for a 'fixed-price' rather than them tackle it if costly - very noble. Tbh, I think you are in f-p territory here.
And if you didn't 'cause' the pressure increase, then there's likely a secondary issue like a failed EV or internal leak going on. Just too many issues, I think...

[Deleted User]

13-year old Ideal Logic+ 24 (Combi) has regular pressure problems so I regularly top it up

That isn’t normal. It suggests either a leak somewhere in your heating system or a leaking PRV. The problem with constantly topping up a heating system is that you are adding water AND air. Together they result in internal rust build up in your heating system. If this ‘sludge’ moves it can block the heat exchanger.

As suggested above, this is one for a qualified heating contractor. It might be something as simple as replacing a PRV and draining and flushing the heating system or it could be something more serious.

FataVerde

ThisIsWeird said:

Do you have a trusted local GS? Perhaps worth calling them in the first instance in case it's a simple issue, and I've known them to suggest going elsewhere for a 'fixed-price' rather than them tackle it if costly - very noble. Tbh, I think you are in f-p territory here.

Thanks! How do I go about getting a "fixed-price" repair? Sounds good but it's the first time I hear about it. Is this via Ideal, the boiler maker? I have a local gas engineer booked for tomorrow, but maybe it's best to go with the fixed price.

FataVerde

And now a few updates and answers:

1. I think I figured out the Nest Thermostat and Heat link. As far as I can tell, the heatlink and thermostat have been set up to only control the heat temperature/controls, not hot water. What confused me is that I have a water icon on the heatlink, but looking at the wiring in the heatlink, mine mirrors this one here which only uses slots 1-3 so it's only set up for heat. https://www.cnet.com/home/smart-home/how-to-set-up-a-nest-thermostat-in-the-uk/    This is backed up by the Nest thermostat, which has no water icon/controls.

2. History: Last year, I called a trusted GS who had installed some radiators for me to take a look at a minor leak at the downstairs radiator, which I thought might explain the constant need to repressurize. I also asked him if he could fix one of my loop valves which was somewhat loose. He fiddled with both but after he left, I couldn't get heat or hot water back on. The pressure went up, then down, just like now. Same fault message "No water flow lockout". A week later he sent a colleague to check the boiler. The colleague said it's water in the fan and the fan needs changing for £500. I researched getting new boilers, but also called an emergency GS engineer for a check. By that point, I was away from the UK and a tenant stayed at my place. The emergency GS came, said it's just the pressure needed topping up, didn't open the boiler and left. I asked him about the fan and he said, the boiler would have been too noisy if it were the fan. BUT, Hot water and heat came on and I had no complaints from the tenant for 8 months. I've been back for two weeks and water was decently warm at first, then got lukewarm, then cold. When I checked the pressure, it was high and I think one of the valves on the loop was in a slightly different position. I asked my tenant if he had problems since the original issue last year and he said no, he just had to repressurize very often.

NannaH

Fixed price repair will come from Ideal themselves, usually around £300 and will cover more than 1 problem if needed. 
DH advises this to customers with major problems like pcb or heat exchanger as it’s cheaper than he can do it for ( the parts cost to him are often more than £300) and he gains a regular customer for his honesty. 

Regularly over pressuring by topping up too much could have blown the pressure valve so it won’t resit properly. 

ThisIsWeird

FataVerde said:

And now a few updates and answers:

1. I think I figured out the Nest Thermostat and Heat link. As far as I can tell, the heatlink and thermostat have been set up to only control the heat temperature/controls, not hot water. What confused me is that I have a water icon on the heatlink, but looking at the wiring in the heatlink, mine mirrors this one here which only uses slots 1-3 so it's only set up for heat. https://www.cnet.com/home/smart-home/how-to-set-up-a-nest-thermostat-in-the-uk/    This is backed up by the Nest thermostat, which has no water icon/controls.

2. History: Last year, I called a trusted GS who had installed some radiators for me to take a look at a minor leak at the downstairs radiator, which I thought might explain the constant need to repressurize. I also asked him if he could fix one of my loop valves which was somewhat loose. He fiddled with both but after he left, I couldn't get heat or hot water back on. The pressure went up, then down, just like now. Same fault message "No water flow lockout". A week later he sent a colleague to check the boiler. The colleague said it's water in the fan and the fan needs changing for £500. I researched getting new boilers, but also called an emergency GS engineer for a check. By that point, I was away from the UK and a tenant stayed at my place. The emergency GS came, said it's just the pressure needed topping up, didn't open the boiler and left. I asked him about the fan and he said, the boiler would have been too noisy if it were the fan. BUT, Hot water and heat came on and I had no complaints from the tenant for 8 months. I've been back for two weeks and water was decently warm at first, then got lukewarm, then cold. When I checked the pressure, it was high and I think one of the valves on the loop was in a slightly different position. I asked my tenant if he had problems since the original issue last year and he said no, he just had to repressurize very often.

As Nanna says. Try ideal themselves, but there are many other options including independents. Try a google for 'boiler fixed price repair'.
I think Ideal are reputable when it comes to this, so I think I'd be inclined to try them first.
Your two local GasSafes seem to be twits. Never use them again :-(
Yes, a faulty fan is usually accompanied by noise, as the part to commonly go are the bearings. Your GS suggested instead there was water in there, on what basis I can't imagine. The fact the boiler went on to function ok for months afterwards suggests not going for a new fan was a good call...
Yes, a combi works independently of the external controls for DHW - it simply fires up on demand. If the DHW 'tap' symbol is showing on the Nest, that suggests it's set up for a system boiler with a hot tank. You need to read the setup instructions :-)
Low pressure is obviously caused by a water loss. It can also be caused temporarily by a failing Expansion Vessel, the chamber inside the boiler that accepts expanded hot water, and replaced it when cool, thereby keeping the system pressure steady. After a while the EV completely stops w...
My fingers are struggling on the phone. Will need to wait until I'm on the PC!

FataVerde

Not sure if this adds any useful information, but

1. after many restarts and fiddling with controls, I now hear gurgling in the radiators when I switch their controls from 0 to 5. But like water, they don't heat up.

2. after repressurizing the system to 1.5 (had to do it again this morning as it was almost at 0), the pressure gauge arrow went up to almost 3 on restart/reset. It then goes down slowly, but stopped around 2 and is vibrating. This has happened last year as well.

Yes, there is no way I'm calling those gas engineers again, but I am baffled how the system worked for a year. And why it always fails when I start using it, haha.

ThisIsWeird

FataVerde said:

Not sure if this adds any useful information, but

1. after many restarts and fiddling with controls, I now hear gurgling in the radiators when I switch their controls from 0 to 5. But like water, they don't heat up.

2. after repressurizing the system to 1.5 (had to do it again this morning as it was almost at 0), the pressure gauge arrow went up to almost 3 on restart/reset. It then goes down slowly, but stopped around 2 and is vibrating. This has happened last year as well.

Yes, there is no way I'm calling those gas engineers again, but I am baffled how the system worked for a year. And why it always fails when I start using it, haha.

Ok, these are useful symptoms.

A sealed system like yours can lose water from one of two places - the boiler itself, or the pipes and radiators. You initially had a leaking rad pipe, so that could have been the first cause.

You now, tho', have something else going on; the system loses pressure (ie water) and requires to be topped back up. But another thing also happens - when you fire up the boiler from cold, the pressure goes up to around 3 bar, before then dropping again.

Inside your boiler is an Expansion Vessel. Inside this vessel is a rubber diaphragm. On one side is pressurised air, which is injected via a tyre-like Schrader valve, and on the other side is the system water. Withe boiler cold, the rubber dia sits pretty much in the middle. When the boiler system water heats up - ie mainly when the rads are on - the sealed water expands and needs to go somewhere. Where is goes is inside the EV - the air side gets squished. When your system cools down again, the water goes back out of the EV and into your CH system. The pressure should remain fairly steady.

If the EV fails or loses air, then the first symptom is usually regular pressure drops, and folk compensate by topping up the system. That appears to work for a while! But when the EV is empty of air, then the pressure rises as there's no more room for the expanding water to go. When the pressure hits ~3bar, a safety release valve inside the boiler is forced open, and excess water and pressure is dumped out via a discharge pipe which is 15mm, copper, and ends up outside near the boiler, pointing at the ground or the wall. With your system having dumped this excess water, when it cools back down - hey presto - the pressure is low. So you top it back up when cold, fire up the boiler, the water expands, hits 3bar, and is dumped again. Rinse and repeat.

Another thing tends to happen also - once the valve is 'blown' open, it often doesn't reseal fully afterwards, so it continues to dribble water, so the pressure will continue to drop even when the system is off and cold.

Your symptoms indicate a failed EV, or one that needs recharging; sometimes the rubber dia doesn't actually fail, so a repump is good enough.

But you also have a separate issue - even when the boiler pressure is 'ok' - ie between ~0.6bar and ~2bar - the boiler still doesn't give you hot water or heating. It should. No idea why that is, and your service fellow will need to find out.

The gurgling is interesting. Sometimes when the rubber dia fails, the compressed air passes into the system water, and that would cause that sort of noise. However, more boilers have an auto air separator which should remove any trapped air. Perhaps yours is faulty.

Things to do - as you organise a fixed-price-whatsit ideally from Ideal:

1) With the boiler off, bleed every rad. Note down what comes out (including the water colour).

2) ID the discharge pipe outside your house, and rubber-band a clear plastic bag over the end. Monitor if anything comes out as you use the boiler.

3) Read the Nest instructions, and see how to set it up for 'combi' boiler use (if it isn't already). The Nest is great - DO use it.

4) If you don't already have a magnetic filter fitted on the return pipe to your boiler, seriously consider paying the ~£150 to have one fitted when the rest of the work is being done (most likely the system water will need draining down for this). You have been running your system will a much reduced level of corrosion inhibitor, so you want to catch any resulting sludge.

5) Write down what's been going on with your boiler, and all the symptoms, so you can fully inform the FPRFellow. Factor in a new dose of system inhibitor when the job is done - they should have this with them.

6) Read the small print on the FPR - see if it covers EVs. Some, surprisingly, do not for some reason (they are not expensive, and are usually a doddle to replace, so I don't get this.)

Yes, I'm baffled too why the system worked for year, and it certainly suggests the original local GSs got it wrong. There's a very good chance that your boiler is generally 'ok', and will work again once the surrounding issues are sorted. If, for example, the auto air vent is blocked so it can't jettison the trapped wind - barp - then bleeding the rads might sort that, but the repair fellow should check the vent anyway.

Keep us posted. And tell us if air comes out t'rads, and if water comes out the discharge pipe.

FataVerde

Thank you for the detailed reply. When I bled radiators so far, the water was transparent with a yellowish tint, so dirty. There was no air in any radiators, water came out immediately.

Another strange thing is that when I switch from summer (tap only) mode to winter mode on boiler controls, the message on the boiler registers the change, but I often have to restart or reset the boiler for the rads to start working (the pressure and gurgling sound) even if they are not heating up. In fact, yesterday, after one of the many restarts, the closest rad in the bathroom did heat up.

I found the info on the Idea site. Looks like this is the category I'd qualify for: 

• A fixed price repair, which includes all required boiler parts plus labour for a one off payment of £345. If we are unable to repair your boiler we will provide you with a partial refund https://idealheating.com/support/out-of-warranty-protection 

They don't have more info on the site, but they seem to say it would cover 'all' boiler parts.

What is a "no call-out fee" service for Gas engineers? I see a lot of them advertising this.

I'll go down to work although I am new to boilers so this might be above my pay grade. Some radiators are also so poorly positioned, they are hard to bleed. From one, the water comes out like an artesian fountain and I don't have that key to turn it down.