Combi Boiler Recommendations

[ALEC1]

In fairness though you only need high flow rates for bath filling and washin up...most people shower nowadays, and have dish washers...


And a decent shower for most people is actually not that great, around 8-10l/m

Flow regulators can balance the distribution..but are notoriously difficult to get at a merchant...

but if you buy expensive taps then they come included..some basin taps as low as 6l/m...they are probably expected to be installed on recirculaion loops...

I notice there is a tapping on vitodens 200s for a well insulated loop...

 

[ChrisR]

If you have common ordinary plumbing with low resistance showers the easier route (closer/lower shower) will take the lions share of the flow. A loft one gets nothing much - exactly the Agile scenario.

If you put highish resistance shower heads on (smaller holes) you get better distribution between showers and fast jets of water with fewer kW. Have still had to restrict a lower one in a situation like that but not too hard to get something the owners find acceptable.
37kW is ok, but as said above, you still need good pressure/flow mains.

If the mains is not quite so good, an electric shower in the loft can be a sensible choice, they only use 4 litres/min.

 

[Agile]

And a decent shower for most people is actually not that great, around 8-10l/m

Are you sure Alex?

Install a proper shower?

Sorry, I hate electric showers with a passion.

Now if you'll excuse me, I'm going to stand under my 22l/min shower whilst it runs my bath

 

[Dan Robinson]

^^^^^^^


I have a 35kW system boiler charging a 300/330litre thermal store with a 100kW plate heat exchanger.


At the time of my last post I was in the bath.


All of which is irrlevant to this post.

So your point is?

 

[ALEC1]

8-10 l/m is fine for a shower, and thats what you will find in hotels for obvious reason...as any shower manufacturer....too much water is as irritating as too little.

I always spcify low resistance shower heads for the attic, and end up installing flow restrictors on the kitchen tap....

 

[landyandy]

I'm quite interested in the new Vaillant ecoTec Plus 837 as they are not too expensive & seem suitable for my property.

I think you are on the right track with this boiler.
Link it with a good installer and you should be fine.

Andy.

 

[silverback]

The biggest combi boilers will only give about 13-14 li/min raised 35 C. When its cold thats more like 11 li/min.

Thats a fair flow for filing a bath and will run a nice shower.

But two showers only giving 6 li/min each will be disapointing! Dan above likes 13 li/min in his shower otherwise he does not find it stimulating!

Both the last two posters know all this and are just baiting me! They are probably at home drunk already as its a Friday evening!

Tony I don't think you fully understand the flow rates of combis, if as you state the stated flow rate is 14 l/min at 35 degrees C temperature rise, that means the boiler can provide 14 l/min with a 35 degrees temperature rise, so if the incoming mains was at 15 degrees, the boiler could supply 14 litres a minute at a temperature of 50 degrees C, if you wanted the water hotter than this, the flow rate would be less than 14 l/min, if in the winter with the mains coming in at 5 degrees C you would get 14 l/min at 40 degrees C, if you wanted the water hotter the flow rate would be less than 14 l/min simply saying "The biggest combi boilers will only give about 13-14 li/min raised 35 C. When its cold thats more like 11 li/min". is quite simplistic

 

[Dan Robinson]

Atag Q51c anyone?

 

[silverback]

Atag Q51c anyone?

Good choice

 

[Agile]

simply saying "The biggest combi boilers will only give about 13-14 li/min raised 35 C. When its cold thats more like 11 li/min". is quite simplistic

I think that I do understand combis!

Of course my answer to the OP is simplistic! He is a home owner without specific knowledge of plumbing.

What he does need to know is that a combi wil not run two good showers at the same time!

Many installers seem to think its better to get the job fitting something which is not going to be totally adequate. Its their pocket being lined!

Tony

 

[silverback]

Just a taste of your own medicine Tony, your posts are very condescending

 

[Agile]

All forum replies are meant to be to the OP !

No one should start sub discussions!

On some forums the mods will delete any replies that are not strictly for the OP.

 

[Dan Robinson]

Buy only when it suits eh?

 

[hansthebear]

I like indian food