Boiler advice please

[FMac]

I have a very old Thorn EMI (Marathon?) boiler. About 9 years ago this was connected to a 135l (corr. 145l) Megaflo, although I'm not convinced it was done correctly. I know that at least one pipe that should have been 22mm was actually reduced to 15mm, and a point where the cold water should have been taken off wasn't used. I'm dubious about the wiring also.

(Apologies for this poor description - I'm in IT not plumbing - I could take photos if it would help)

Anyway, I'm having an extension built where the flue currently is, so need a new boiler.

Should I go for a system boiler and use the Megaflo. (~£500 - £750 plus fitting)

The builder's plumber would be expecting to do the install, and although he's installed combi's etc., I'm not sure he's experienced with these systems, certainly enough to correct other's mistakes.

Or should I replace the whole lot with a Worcester Greenstar Highflow 550CDI. (~£1800 plus fitting)

It's a biggish house (4/5 beds 3 baths, at least two showers simultaneously). I have been known to use up all the hot water in a 10 min shower.

Sorry for the length of the question.

 

[Puddle]

Well firstly to work on a pressurized system, like your mega flow, you need to be registered, if your builder has someone registered, on problem, if not get someone who is and I am sure they will be able to sort installation out to run correctly and safely
Secondly you have answered the question about keeping the system yourself by saying at present you run out of hot water in 10/15 mins, which is not accebtable, if you can go to the expense of a worcester high flow you will be very happy with it ,as long as you have up graded you water main into property/increase size as required ,which if not I am sure your builder will be able to do
And thinking about it if you have to replace the boiler and the mega flow to a bigger unit the cost will not be that much different

 

[flat pack]

a builder for bricks ...
a plumber for pipes...
a unvented installer for unvented hot water
a gas safe installer for gas...
and a IT for IT

GET THE RIGHT TRADES IN FOR THE QUOTES

SOUND TO ME THE LAST OUTFIT YOU HAD IN WERE COWBOYS

ALWAYS READ THE LABEL/CARDS. AND CHECK THEY ARE REGISTER


YOU ONLY HAVE ONE HOUSE
GOOD LUCK

 

[FMac]

Puddle/Flatpack - Many thanks for the answers.

Yes, I was never absolutely comfortable with the previous work, (yee-hah) but wasn't aware there were additional requirements over the CORGI bit at the time.

I did ask this time about being qualified for unvented systems and didn't get a reply I was happy with (i.e. obviously not), so wanted to know if the megaflo was worth sticking with before going elsewhere (for this portion of extensive changes).

I believe the plumber is gas safe, but will be checking before he does the boiler and/or hob work for me. He has definitely done this sort of work elsewhere.

Now off to sell my body for the extra money - it will probably take some time.