Replacement boiler recommendations wildly different

[adwoot]

Hi

I am currently getting quotes for a replacement for my elderly Servowarm Elite 50 boiler. Though it works, it is struggling and seems to be running at the top end of capacity. So far had British Gas and NPower in, and although the quotes are broadly similar in cost like-for-like, the actual boiler spec varies significantly.

BG have specced a 330+ Condensing boiler, which I believe is 31.6KWh output
NP have specced a Glowworm Flexicom 18hx, which I believe is 18KWh output

Both have done a site survey, although BG was a proper surveyor rather than salesman and took detailed measurements to give the volume of the property. I have 9 rads of mixed sizes, though my rooms are quite big with high ceilings.

Three questions really -
1. What should I go with? I do think 18KWh is too small for the house, but don't want to pay a premium for spare capacity, and don't know enough to make an informed choice.
2. What is the output of the Elite 50 as a comparison?
3. Any recommends/advice for an alternative supplier (I live in North West Wales)? Have a local company giving a quote tomorrow.

Thanks in advance!

[temps]

Hi
Forget BG or NPower, go with a local smaller fitter as price will be a LOT cheaper and they will recommend. I would go for a worcester EVERY time!! But then thats all i fit as the product is very reliable!!

Happy hunting!!

[adwoot]

Hi
Forget BG or NPower, go with a local smaller fitter as price will be a LOT cheaper and they will recommend. I would go for a worcester EVERY time!! But then thats all i fit as the product is very reliable!!

Happy hunting!!

Thanks, have got a price from a local fitter but not that far off the NPower quote.

Question still over output - local fitter has specified a 28KWh boiler, Npower 18KWh and BG 31KWh, looking for reassurance over which output is best suited as a replacement based on existing boiler and number of radiators!

[giveusaclue]

Hi, I'm not a tradesperson at all but I have recently had to buy a boiler. I used a heat loss calculator to estimate the heat loss from each room (there are lots on the web but I used this one http://www.aeon.uk.com/pages/heat_loss_calculator.php ). It shows the estimated heat loss in watts and also the equivalent BTU s required from radiators etc. I added all the wattage together for each of the rooms. It is recommended that you add 3kw if you still have a hot water cylinder (instead of combi) and add 10% of the total to account for very cold weather. This overall figure should give you the central heating output that you need. I'm afraid I can't really comment on the DHW (domestic hot water) rate. I only have one bathroom so this wasn't too much of an issue.

[scolly]

hi was just reading this and thought i would comment that the british gas 330 is a glowworm boiler as im sure you know but what they dont tell you is that when british gas fit the boiler it comes factory set to 18kw and im sure that the british gas installer will not adjust this, there is a small potentiometer on the pcb in which can be adjusted to set the boiler anywhere from 18-33kw, if the installer breaks this seal then he must ensure that the gas supply is capable of supply enough gas to a 33kw boiler and in most cases would have to upgrade the gas supply from 15mm to 22mm for part of the run at least. so although it may say that you are getting a 33kw boiler in fact you are getting an 18kw boiler which can be upped to 33kw if required. sounds to me like n-power and and british gas are putting in the same size boiler!!