Baxi 105e - slow heating problem

[extragonk]

Hi there!

first post so please be gentle

We've got a Baxi 105e boiler installed at home and while i've read around about the noisy o rings and such like (which i think it suffers from as its very noisy) i havent seen reference to our problem.

when the hot tap is opened we instantly get around 1 pint of hot water, it then runs completely cold for approximately 2-3 litres (mixing my scales i know, sorry!) before is slowly comes back up to temperature.

Any pressure changes to hot or cold systems will force a repeat of the cold to slow warm cycle, even the most minute of adjustments will cause this.

obviously this makes for interesting temperature adjustments under the shower etc and it increadibly wasteful of water due to the volume of cold it generates.

the previous owners of the home did say they enlarged the mains water inlet pipe to accomodate the massive showerhead - however it looks the same size as the last property we were in and the boiler doesnt exceed 2 bar of pressure.

could anyone help me with what this would seem to indicate? is there any further information you'd need to diagnose a problem i could get an expert to fix?

thanks!

 

[corgiman]

thats combis for you

the intial hot water you get is because of the water in the boiler getting hot when the boiler is on centralheating, or, if its an instant version, in the heat store.

Combis are not that instant and the temp will drop off while its trying to heat the plated heat exchanger

you can around this (sort of) by insulating the hot feed pipes to your taps, this will help keep the hot water in them hot for a time.

combi boilers are crud

 

[extragonk]

hehe doh, i thought that might be the answer, i was hoping this boiler was well known for slow heating or maybe the mains pressure was feeding thru the system too fast. our last place didnt suffer the same problems nearly as much as this boiler does.

tackling it from a slightly different angle, what would be the recommendation for shower type with this boiler in mind - i think we have just a straight mixer at the moment and its awful.

although i've read up on gravity fed systems im a bit bemused on mainflow systems, how does it heat the water and maintain mains pressure?

thanks!

 

[kevplumb]

although i've read up on gravity fed systems im a bit bemused on mainflow systems, how does it heat the water and maintain mains pressure? icon_smile.gif

because it cuts the flowrate down

 

[corgiman]

although i've read up on gravity fed systems im a bit bemused on mainflow systems, how does it heat the water and maintain mains pressure? icon_smile.gif

because it cuts the flowrate down

and therefore it takes longer for the hot water to reach your tap