New oil combi boiler

[finnvanb]

Hi

I have just bought a property and am looking at installing an external oil combi boiler and require advice.

I have a semi detached bungalow and will be looking to convert attic in the future. Space is tight and I would prefer not to have any tanks in the attic space to maximise space for conversion, hence the combi boiler.

Property: Living room 4.8m x 3.5m
Kitchen 4m x 2.5m
Bed 1 4.2m x 3.2m
Bed 2 3.5m x 3m
Bathroom 2.5m x 1.75m
Hall 4.8m x 1.5m

Potentially 2 further bedrooms and small shower room in attic. Property has cavity wall insulation and double glazing throughout.

What size boiler should I be looking at and what are the best brands currently.

Cheers

Finn

 

[lame plumber]

get a qualified plumber to come and quote for the work, they can then survey the place account for floor, wall and roof types etc and window sizes and types and give a definative answer. Or just go for the best HW flow based on output and the heating side will be fine.

 

[Best]

And avoid all oil combi boilers completely. There is not a good oil Combi. They all are expensive to buy & expensive to keep fixing & they give trouble constantly. Over complicated badly engineered boilers that you depend on for hot water. They are so bad, I am thinking of refusing to work on any of them.
Consider getting a non Combi with a unvented stainless steel cylinder. It might be worth putting both in a small purpose built extension at end of your bungalow perhaps.
If you do still insist on a Combi oil boiler, avoid Warmflow, trust me! Take a look on problems with Combi oil boilers on Internet.

 

[lame plumber]

sssssssssssssssshhh I love them

 

[Best]

sssssssssssssssshhh I love them

££££££££££££££££ :hurray:

 

[lame plumber]

they only fail if they are installed badly and never serviced, done properly they are the same as any gas combi

 

[SimonG]

If you are looking at extending then boiler plus unvented. But you need somebody round to check everything out.

 

[Best]

they only fail if they are installed badly and never serviced, done properly they are the same as any gas combi

Seem a lot less reliable than gas combis from what I see. I fitted a Warmflow Combi that the owner/builder bloke insisted on & it has so far been a disaster IMO. Leaks from the factory parts.
I fitted it well & serviced it nicely. Had to go back a few months after I serviced it so I could again service it for new tenants coming in. Shocked me to find AAVs leaking.

 

[lame plumber]

I didnt say that warmflow word, you deserve everything you got for working with the devil!!!

 

[SimonG]

Not had a problem with a Warmflow yet. Two downers for me though, the plastic flue and the low pressure switch that needs to be re pressured to one and a half bar to reset.

 

[Best]

I avoid the Warmflow combis, but have seen one leaking inside the shell & was replaced free of charge by Warmflow. I have heard of that happening lots of their Combis & standard condensing boilers. Seen too many of their std eff boiler shells leaking when only a few years old.
I don't like the way the rather lightweight baffles have to be carefully staggered each time you service them. I also hate the secondary heat exchanger having a door on it & also that the gasket perishes. I don't like their thermostats. I also think they could be more efficient boliers. They do run nice & quiet though.

 

[finnvanb]

Thanks for replies folks. I'm definitely getting the idea from much reading that combis are best avoided. By stainless steel unvented do you mean a hot water storage tank located within the house? I have had a two plumbers out, one suggested a 36kw and the other a 28kw. As I would be running at most 10 rads and predominantly use electric showers I'd be tempted to go for a smaller boiler. Is that a correct assumption to make?

 

[Best]

Unvented cylinders can be fitted anywhere strong enough to support their weight full of water & protected against frost. Ground or higher floors, attics, garages or boiler rooms.
Preferably as close to most hot water draw off & close by the boiler (gas or oil).
I did the plumbing & heating on a bungalow roof conversion last year & chose to fit an unvented system. The unvented cylinder was installed on ground floor in what luckily was a previous small toilet room of about 0.8 metre width. If you have a space of a typical small airing cuboard somewhere on ground floor of maybe as little as 0.7 x 0.7m, you have plenty of room for a cylinder.
A boiler room linked to the bungalow that is just big enough for a oil boiler & a cylinder & some space for you to step in, will keep everything out of the bungalow, but beside it.

 

[WHPES]

Seem a lot less reliable than gas combis from what I see. I fitted a Warmflow Combi that the owner/builder bloke insisted on & it has so far been a disaster IMO. Leaks from the factory parts.
I fitted it well & serviced it nicely. Had to go back a few months after I serviced it so I could again service it for new tenants coming in. Shocked me to find AAVs leaking.

My experience with Warmflows mirrors this, Firebirds also leaky.

I've fitted a number of Grant combis and provided they are regularly serviced, are generally trouble free.

 

[Best]

My experience with Warmflows mirrors this, Firebirds also leaky.

I've fitted a number of Grant combis and provided they are regularly serviced, are generally trouble free.

The big Warmflow factory is only a few miles from me & I wish them well. Some of their boilers are going for near 30 years & they were easy to service. Sadly I haven't been impressed with Warmflow for a number of years & tended to use only Worcester Bosch or Grant. The Warmflow Combis are poor no doubt & I really will avoid them. I have no wish to support Grant boilers & would prefer UK made, but I do like Grant domestic boilers record of giving good service generally & they have had great success with the Vortex model.
People seem to like the green outer case on Warmflow boiler. Grant galvanised outdoor module is a bit in your face IMO. But I still would go with it.

 

[finnvanb]

So after much deliberation I have decided to go with a Worcester bosch danesmoor 18/25 external system boiler in conjunction with an indirect unvented 180 litre tank. Hoping that this is a good combination for my circumstances.

 

[Gray0689]

180 litre why that size?
How many people in house potentially

 

[finnvanb]

Thanks for reply, I've gone that size as there is two of us, should give room for expansion at some point no?

 

[Gray0689]

180 isn't allowing for expansion at all

 

[finnvanb]

All we have in the house are two sinks and a bath. Showers are electric. Surely 180 litres is enough? What would you suggest?

 

[Gray0689]

Why would you have 2 electric showers with unvented lol

 

[SimonG]

You wouldn't.

 

[Gray0689]

210 with at most 1 electric shower if you must
But better for 2 thermostatic mixers
But that's just my opinion

 

[finnvanb]

My issue is lack of space...hence the smaller tank. I am going unvented due to not wanting additional expansion or cold water tanks in the attic space.

 

[finnvanb]

I'm also currently looking for a receiver wired into the boiler with a wireless programmer/room thermostat. Any suggestions?

 

[Ermintrude]

Get a ACV the tanks deliver more water for the space due to higher storage temp and blending it to lower temp at outlet thus more water for the space. Faster recovery. Also builtin controls are awful when they go wrong and might be superseded or expensive.

 

[Gray0689]

Heatmiser neo if you can go wired

 

[finnvanb]

Was looking at heatmiser I'm sorry ermintrude that was beyond my understanding, is that a different system?