Time for a new boiler but everyone's advice is conflicting!

[bengasman]

1. Will it cost me less to install a replacement Combi rather than convert to a system boiler

A lot less

2. Are new Combi's any good?

Good quality combi properly installed is great, cheapo installed by cowboy is worse than you have now.

3. Can I trust BG to do a good job?

No. They have some really good ones, a lot of really crap ones, some subbies, and you have no influence on which one will do the job.

4. Which brand would you recommend (cue conflicting opinions!)

Viessmann without a shadow of a doubt.

5. What Model and KW would you recommend?

Provided it won't cost a whole lot extra for the gaspipe, 100w 35 kW, or smaller if lower cost is more important than new gaspipe.

7. How long might the work take, assuming it's a replacement combi, rip out old, plumb in new, test etc? 2 days? 5 days?

How long is a piece of string?

One problem though, your current hot water flow going up and down is unlikely to be caused by the Puma.

 

[kevindgas]

OP as you have a combi already then a replacement combi will be the most cost effective

as for boiler manu's my prefered are as follows 1. vaillant 2. baxi/potterton or glowworm 3. vokera or main the only 1 i would avoid like the plague is Ideal (their customer service is as non existant as their warranties!)

i would look at 28kw as a minimum (we use vaillant 831's mostly)

as for installer then again i'm sure an independent will give you a cheaper quote than BG

if I was doing the work (single handed) i would expect a day to change over and a half day to finish off/tidy up

 

[holty]

e.g. Turn on hot tap, hear boiler fire up, water flows is weak and cold, water flow gets better and slightly warm, then dies away to a dribble, then 20 seconds or so later when the boiler has got itself sorted the flow increases and the temp does too and then it stays constant.

not read all the posts as i find this a topic covered a million times over. but this is a product that might be of interest
http://www.combisave.com/

as for boiler i wont touch worcester. fitted 150-200 wb1b viessman and service agent for my patch and only 4 call outs each being an installer fault or regulator on lpg. thats in 3 years. besides that vaillant .otherwise. if you want the nuts then rinnai twinflow. basically a water heater coupled with an atag boiler. both the nuts. good flow rate.

 

[transam]

Combisave another one that may be worth a look at is the energycatcher in conjuction with a combi store

 

[adamtw36]

OK, some updates:

I had BG in for the first quote, a lot of sucking of teeth etc as expected. Thought this would be a good 'worst case scenario'.

measured my water flow rate, its about 15l/m, so not great, that rules out a megaflow type boiler as far as I understand it.

He sucked his teeth about the existing flue vent, that its not fan assisted and says they all should be now = extra cost.

He sucked his teeth about the boilers external overflow/drip pipe (don't know the proper term) Said they would do a new one and have it heated? Sounds ridiculous to me, I know condensers are different and we had some cold weather but is this going to add much cost I wonder?

The Potterton Puma has a 15mm gas in-pipe. He sucked his teeth once more, said all modern boilers need 22mm. I have since found it is 22mm all the way to the boiler, just throttled down to 15mm for the final 18 inches, ergo, not a problem.

I asked about other brands they sell, like WB, Vaillant etc. He basically said why buy a WB when the BG ones were made by them. He also said that Vaillant were very unreliable.

His recommendation was a BG 532 boiler, combi (reckons they are made by WB). Said it would be good as it has an internal tank of water to get hot water to the tap quickly. I mentioned that WB and Vaillant both do this and he seemed to poo-poo that notion and that BG invented it.

Said it would be in the region of £4k....thud.

The whole experience was unpleasant, felt like a cheesy salesman (and I work in Sales so I have seen plenty of them). I was glad he didn't stay long.

Time to start getting some other quotes.

 

[adamtw36]

Oh, and regards to our cold water pressure, there is never any variance at the tap. It's very constant, never goes up and down, it's the boiler.

 

[Agile]

Your Puma only varies the flow rate if the hot water is cool!

Tony

 

[kevindgas]

I asked about other brands they sell, like WB, Vaillant etc. He basically said why buy a WB when the BG ones were made by them. He also said that Vaillant were very unreliable.

His recommendation was a BG 532 boiler, combi (reckons they are made by WB). Said it would be good as it has an internal tank of water to get hot water to the tap quickly. I mentioned that WB and Vaillant both do this and he seemed to poo-poo that notion and that BG invented it.

Said it would be in the region of £4k....thud.
long.

Time to start getting some other quotes.

1. vaillant are among the most reliable boilers I know fitted, 100+ ecotecs had 2 with overheat issues 418 & 428 (my fault didn't set them up correctly!! durr!) 2. an 831 with faulty diverter valve and finally 3. an 831 with the original rubber hoses that leaked

£4k !! for a boiler change what is uit gold plated? £2.5k tops

get a couple of quotes off local guys

 

[hansthebear]

imagine a BG guy suggesting the condensate should be terminated and protected properly, how very dare he.

 

[dcawkwell]

1. Will it cost me less to install a replacement Combi rather than convert to a system boiler and should it be fairly straightforward i.e no need to rip open walls and pipes etc (It's all in the airing cupboard upstairs with visible pipework and doesn't need to be pretty)
---
System boiler will be fine. You could install a combi and use it
to heat the hot water tank and supply some of the hot water say to
the kitchen if you wanted. Then swap over to the combi for the whole
house at a later date or stay as you are.
--------------


2. Are new Combi's any good? Will I still be waiting a minute for hot water to appear at my taps?
---------
Wouldn't have a combi in my house. If you get a combi you need an electric shower as backup for when the boiler breaks down.
Of course if you have a hot water tank you are fine. Immersion heater.
----------

3. Can I trust BG to do a good job?
----
No, they employ a bunch of subcontractors most of the time.
-----------

4. Which brand would you recommend (cue conflicting opinions!)
------
Personally cheap and cheerful. But that is me.
Every boiler manufacturer makes good and bad models. Some are better
than others. Some will run reliably years after year the same model will breakdown straight away. Depends a lot on installation and the building as
well as load etc.
---------

5. What Model and KW would you recommend?
---------
30kw combi. Or 24kw system boiler
---------------

6. Does anyone know a good reliable installer in the East midlands (Melton Mowbray area)
--

7. How long might the work take, assuming it's a replacement combi, rip out old, plumb in new, test etc? 2 days? 5 days?
---------
back boiler to combi 2-3 days.
------------------

Many thanks for all help, opinions and suggestions.

 

[bengasman]

He sucked his teeth about the existing flue vent, that its not fan assisted and says they all should be now = extra cost.

Total nonsense; a boiler is what it is, it doesn't cost anything extra.

Said they would do a new one and have it heated?

Total nonsense; trace heating is one option but there are other ways. Besides, the Puma doesn't have a condensate pipe in the first place.

He sucked his teeth once more, said all modern boilers need 22mm.

Total nonsense; a boiler needs a certain gas volume, not a certain diameter gaspipe. 22 is common, but could be less or more.

The whole experience was unpleasant, felt like a cheesy salesman

Sounds like it. I've heard more than one BG engineer who doesn't like the salessharks.

 

[TheGasMan26]

Agile has stated some very good info. but as you've got inadequate pressure for a megaflo that rules out an unvented(check this with a several installers) system. converting to an Open vented system will add loads to the amount.

Best balance between price and performance would be A very good combi ideally with weather compensation(outside temperature sensor hooked to boiler), full powerflush of system and a magnabooster system filter fitted, TRV's & a programmable room stat.

in my experience the top 2 are vaillant/worcester bosch, though a good installer that knows what hes fitting may suggest other valid choices, such as a veismann. If you buy a high rated boiler(30kw or more) & its fitted well HW performance should not be an issue. However there will be a small delay depending on distance to boiler.

If you wanna spend a bit more for high HW performance & instant HW then a combi store(mini cylinder usually located under combi) and an energycatcher(sits on top and takes every last bit of heat from fumes, also elliminates pluming which is the steam you see coming from new condensing boilers).

But if cash isnt an issue then a proper system with a decent cylinder & elevated HW tank in loft(or booster pump on incoming supply) & a good system boiler(smaller than combi), all this also depends on the size of your house.

 

[Agile]

The final choice of the best system will need an assessment of the number of people who live there and their hot water useage1

Tony