Worcester 30i or 28/32 CDI compact? Please advise!

[Shimlasun2]

Hi thanks for reading. I have a fairly old semi detached 2/3 bedrooms, 2 bathrooms (showers mains but not often used same time). Existing old combi 22mm piping at gas meter and at boiler but quite a long route from basement at front of house to boiler at back of house (around 20-25m as it seems to go upstairs before coming down into top of boiler) plus 7/8 bends / corners of some sort (I don’t know what type). I’ve had several accredited installers in. Some are very concerned about the pipework and say can’t go any bigger than 28 CDI compact or 30i, without needing a lot of expensive pipework .. but couple have said a 36 CDI compact should be ok with existing pipe work. They mostly all said can’t be sure until installed and check pressures either end but still I don’t want to play it super safe and get an undersized boiler, but don’t want to get something too big I end up with a huge pipework bill. Any advice?

Also I know the CDI classic is the best Worcester B boiler but understand they’re discontinued plus I have very little space. Would you say avoid 30i and go for 32 CDI compact and this range is better quality?

Thanks in advance - I’m pretty confused!

 

[ShaunCorbs]

36 kw will definitely need 28mm pipework tbh depending on the route / length the 28kw may need a partly upgrade to 28mm

 

[centralheatking]

Hiya, I fail to understand why you feel you need to upgrade rather than replace with a contemporary similar model. is the existing boiler inadequate ? You have stated your needs and you seem happy with the
performance. All I am asking is why go to massive upheaval and expense ? centralheatking

 

[Shimlasun2]

Hi thanks for your replies both.

ShaunCorbs - would you tend to recommend 32CDI or 28CDI compact over the 30i for a house my size? I have good water pressure - 16L/min - so would you recommend having the larger 36kw boiler to match that?

centralheatking - the existing boiler is a 15 year old glowworm (100e, 30kw I believe) which has caused problems since I've been here, broke down once in between Christmas and NY, then all last winter it leaked intermittently and water only luke warm most of the time. I got several people to look at it all of whom said would be £400-500 to access the parts that needed replacing which they felt wasn't worth it so I just got by with it as it is... and it didn't matter in the summer plus we've had illness in the family so fell off the radar. So I don't really know what my requirements are - current boiler not adequate but it's not working well so no idea whether if it were working well whether it would be enough.

There are two of us here at the moment, but might be more in future.. I have 8 radiators, and 2 bathrooms but not a huge issue if can't use both showers at exactly the same time... as I understand it that's not what combi boilers are for anyway? It's just that I've had a range of advice from
"you have really good water pressure 16L/min and so you should have a boiler that matches that i.e. the 36 CDI"
to
"your pipework could need a huge amount of work to support a new energy efficient 30 / 32 kw boiler so better stick with 28 kw"

Hence the confusion!

 

[ShaunCorbs]

If you don’t want to use both at the same time the 28 compact is a decent boiler and depending on installer could be upto 10 years warranty with a filter and Worcester controls if serviced every year

If you do want to run both at the same time have a look at Viessmann 111 (26kw-35kw)

Gloworm offer a fixed price repair if required around £280 mark and will fixed all problems

 

[Shimlasun2]

Thanks for this - would you choose the 28 compact over the 32 compact? Also would you avoid the 30i for any reason? thanks again

 

[ShaunCorbs]

no all good boilers but as you increase your gas main will also as ive said above even with a 28kw you may need to upgrade depending on your situation

 

[Shimlasun2]

oh I see it's the pipework which limits things.
Will the Veissman 111 have a better change of running on the 22mm pipework vs the Worcester 32 compact do you think?

 

[ShaunCorbs]

oh I see it's the pipework which limits things.
Will the Veissman 111 have a better change of running on the 22mm pipework vs the Worcester 32 compact do you think?

Need to get someone out to calc what your pipework can take / load normally do this when they quote for the job