Ideal Logic Combi 24 no hot water or heat

FataVerde

Another thing I wonder about is if a mains water pressure of 12.5l/m would be ok for a combi boiler. I've had a 24 combi so I guess yes, but many posts online say you'd meed much higher flow rate or that you need to measure the dynamic flow rate.

[Deleted User]

Opentherm boiler control is explained here:

https://www.draytoncontrols.co.uk/news/opentherm-explained

The analogy most often used is driving north to south across a city. The controller sets a speed such that all traffic lights that are passed are at green; that is, Opentherm reduces the number of start/stop boiler cycles which increases overall efficiency and reduces boiler wear and tear.

FataVerde

OpenTherm looks good, but can't find a lot of gas engineers willing to install Viessman. They are all about Ideal and Vaillant.

FataVerde

Just a few pics I snapped of the inside of the boiler while the GS went to get the paperwork 

BUFF

FataVerde said:

Another thing I wonder about is if a mains water pressure of 12.5l/m would be ok for a combi boiler. I've had a 24 combi so I guess yes, but many posts online say you'd meed much higher flow rate or that you need to measure the dynamic flow rate.

l/m is flow rate not pressure.

re. Opentherm - both Vaillant & Worcester (& indeed Viessmann also do on some models) have their own equivalents albeit they are proprietary. In fact there is some evidence to say that manufacturer proprietary systems actually perform marginally better (presumably more tailored to the hardware) so I personally wouldn't choose/reject on that alone.

ThisIsWeird

FataVerde said:

Just a few pics I snapped of the inside of the boiler while the GS went to get the paperwork

Nothing unusual there, apart from the obvious puddles... I'm assuming that the leak is from the mainX - the 'heat engine' - since the GS said it needed replacing. There's nothing in these photos to suggest that any other part is at fault, not that it would be obvious anyway! The EV might just need an air recharge, for example, but you can't tell without testing it; you unscrew the cap from the Schrader valve, and press the wee pin just as if you were letting your neighbour's car tyres down. If any water spurts out, the rubber dia is blown. If no water comes out, then fair chance a good few pumps with a tyre pump will sort it. You can try this test for fun - no harm, since the boiler is almost certainly junk...

But, the mainX is around £450, and many FPRs won't cover them for that reason.

FataVerde

ThisIsWeird said:

Nothing unusual there, apart from the obvious puddles... I'm assuming that the leak is from the mainX - the 'heat engine' - since the GS said it needed replacing. There's nothing in these photos to suggest that any other part is at fault, not that it would be obvious anyway! The EV might just need an air recharge, for example, but you can't tell without testing it; you unscrew the cap from the Schrader valve, and press the wee pin just as if you were letting your neighbour's car tyres down. If any water spurts out, the rubber dia is blown. If no water comes out, then fair chance a good few pumps with a tyre pump will sort it. You can try this test for fun - no harm, since the boiler is almost certainly junk...

But, the mainX is around £450, and many FPRs won't cover them for that reason.

That's what I was wondering. The GS didn't test anything, just took the main cover out, took a look and said it's too expensive to repair. He's also the same guy who serviced the boiler before I bought the house a year and a few months ago. And he comes from a highly recommended local company. I have yet to meet a GS I trust.

ThisIsWeird

FataVerde said:

That's what I was wondering. The GS didn't test anything, just took the main cover out, took a look and said it's too expensive to repair. He's also the same guy who serviced the boiler before I bought the house a year and a few months ago. And he comes from a highly recommended local company. I have yet to meet a GS I trust.

Can't really comment much further, as GSs (should) know a lot more than I do. I guess there was some way that he diagnosed a major issue, other than just the fact there's liquid there? I mean, there's a condensate syphon there with stains around it - these can leak, and that would be a very minor issue. So I'm guessing he traced the stains to the mainX, and knew that it was a 'definite'.

Really don't know what to suggest. If the FPR will items as costly as the mainX, then I'd be tempted - the worse case is you lose £99.

Dilemma :-)

FreeBear

FataVerde said: How much does OpenTherm compatibility save, I wonder? I looked mainly at Vaillant EcoTec Plus, the premium range for Vaillant, which seems to have good modulation rates. Got the best quotes from Glow Green so far with:

EcoTec Plus 32  £2,380 

Modulation (max/min) 1:6.1

Nominal heat output range at 50/30˚C (Condensing mode) 5.7 - 25.7

Domestic hot water flow rate 13l/m

Both come with default warranty of 5 years, which is extended to 12 years if you sign up for their care plan:

4. In order to obtain a complete full 12 years, warranty the homeowner must agree to use

Glow Green Ltd (Glow Care 100) for the full service obligation of the appliance and

system.

How much does OpenTherm save - Probably very little, But for me, it offers a way to integrate it in to my home automation system at minimal cost. The savings to be had will be down to having different temperatures set throughout the day/week. This can be achieved with a "smart" programmable thermostat such as Hive or Wiser, and you could potentially save 10-15% with one.

With the cold water flow rate you have, the EcoTec 32 should heat the water to a decent temperature - Side note. Vaillant will provide a 10 year warranty as long as the boiler is installed by one of their approved fitters - The minimum CH heat output is going to be way more than you need, so that particular model will be short cycling for much of the time. In comparision, the Viessmann 050-W will go down to 3.2KW.

Measure up your radiators, find the approximate rating for them, and add it up - I suspect you will have something in the region of 5-7KW* (I have ~11KW in total in a 3bed semi). A WB Greenstar 4000 30KW will probably be just the ticket. Will modulate down to 3KW from around 25KW, and will heat 12.3l/min of water by 35°C (has a flow regulator fitted, so you can reduce the water flow if you want hotter water). 10 year warranty as standard, and someone like Boxt will be able to install for around £2300.

Any company that insists on you using their "care plan" to maintain the warranty is not worthy of consideration in my book - They have you by the short & curlies for the next 10-12 years and are tied in to what ever price they want to charge for a service. Got offered a service plan for my boiler at only £8.99 a month. Can get a Viessmann engineer to do an annual service for ~£60, and that extra £48 doesn't provide any worthwhile incentive.

Regardless of where you go for a new boiler, pay at least £100 on credit card, and you have an additional layer of protection. So if GlowGreen go bust and Vaillant won't honour the warranty, you can pursue the credit card company.

*) Note - Ideally, you want to do a full heat loss calculation to find out what the minimum boiler rating is required to maintain the property at a comfortable level. It will probably be a lot less than the heat output of the radiators.

FataVerde

FreeBear said:

FataVerde said: How much does OpenTherm compatibility save, I wonder? I looked mainly at Vaillant EcoTec Plus, the premium range for Vaillant, which seems to have good modulation rates. Got the best quotes from Glow Green so far with:

EcoTec Plus 32  £2,380 

Modulation (max/min) 1:6.1

Nominal heat output range at 50/30˚C (Condensing mode) 5.7 - 25.7

Domestic hot water flow rate 13l/m

Both come with default warranty of 5 years, which is extended to 12 years if you sign up for their care plan:

4. In order to obtain a complete full 12 years, warranty the homeowner must agree to use

Glow Green Ltd (Glow Care 100) for the full service obligation of the appliance and

system.

How much does OpenTherm save - Probably very little, But for me, it offers a way to integrate it in to my home automation system at minimal cost. The savings to be had will be down to having different temperatures set throughout the day/week. This can be achieved with a "smart" programmable thermostat such as Hive or Wiser, and you could potentially save 10-15% with one.

With the cold water flow rate you have, the EcoTec 32 should heat the water to a decent temperature - Side note. Vaillant will provide a 10 year warranty as long as the boiler is installed by one of their approved fitters - The minimum CH heat output is going to be way more than you need, so that particular model will be short cycling for much of the time. In comparision, the Viessmann 050-W will go down to 3.2KW.

Measure up your radiators, find the approximate rating for them, and add it up - I suspect you will have something in the region of 5-7KW* (I have ~11KW in total in a 3bed semi). A WB Greenstar 4000 30KW will probably be just the ticket. Will modulate down to 3KW from around 25KW, and will heat 12.3l/min of water by 35°C (has a flow regulator fitted, so you can reduce the water flow if you want hotter water). 10 year warranty as standard, and someone like Boxt will be able to install for around £2300.

Any company that insists on you using their "care plan" to maintain the warranty is not worthy of consideration in my book - They have you by the short & curlies for the next 10-12 years and are tied in to what ever price they want to charge for a service. Got offered a service plan for my boiler at only £8.99 a month. Can get a Viessmann engineer to do an annual service for ~£60, and that extra £48 doesn't provide any worthwhile incentive.

Regardless of where you go for a new boiler, pay at least £100 on credit card, and you have an additional layer of protection. So if GlowGreen go bust and Vaillant won't honour the warranty, you can pursue the credit card company.

*) Note - Ideally, you want to do a full heat loss calculation to find out what the minimum boiler rating is required to maintain the property at a comfortable level. It will probably be a lot less than the heat output of the radiators.

Actually, you got me hooked on the Viessmann 050-W 30KW I checked its specs yesterday and really like the fact that it can cycle down to 3.2, but on DHW, it can heat up pretty much as much as my mains water flow. I like that it has solid German construction like the Vaillant, but is compatible with OpenTherm and has weather compensation. I already have a Nest thermostat and Heatlink and now that I understand what they can do, I'm excited about using them (I was so confused by them originally, I set them on manual). I've been watching this guy on efficiency and the limitations of Vaillant's control system in the UK especially https://www.youtube.com/watch?v=wFOpHNz7Fdc 

Yes, I realised yesterday that Glow Green basically makes you pay £500 in care plan for the first 5 years when you could get the boiler serviced for £300 only for those years. It is exactly a just 8.99/month plan lol

It's just a pity Heatable, which have good reviews, increase the price of the Viessmann 050-W 30KW to 2,770, but I found it with an alternative, smaller firm hugboilers for £2090 and 10 year warranty. I just need to read the small print to make sure what I am getting.

On heat loss, I live in a small first floor flat in an old Victorian house that has double glazing and minor loft insulation, but also has a large staircase and hallway that enlarge the heatable area. It's just a one BR but I'll likely extend into the loft for a 2nd bedroom. I currently only have 4 rads. Not knowing the things I'm learning now, I replaced a double fin rad with two single fin ones in the living room because the original rad was in an odd position, behind the couch. I haven't yet spent a winter in this flat, but found out during the heatwave just how ridiculously poorly insulated these houses are. I've grown up across the pond and lived with central heating most of my life so this is all relatively new territory for me.