new home, long wait for hot water

[plumAJP]

i have just moved into my new house, 1950s 3 bed.

it has a worcester combi boiler. when i turn the hot water taps on the demand light on the boiler turns on, it ignites andthe pump runs.

but it takes literally 2 mins to get hot water to the kitchen tap which is on the same level as the boiler and it literally takes 5 mins to get hot water to the bathroom sink (1st floor).

water presure is on 1 bar, theres no leaks etc.

why does it take so long to get hot water?

my other property had a conventional boiler and I never had an issue with hot water delivery.

any help appreciated.

 

[Rico99]

Hi there,

First off, the 1bar on the front is the pressure in the central heating side and nothing to do with the flow of hot water.

As for the time being taken, that is mainly down to 2 things, the length of pipe runs to each outlet and the flow rate of the incoming cold mains.

Rico

 

[plumAJP]

the cold water flow/ pressure is pretty good, it flows out of the cold water tap very quickly and spalshes everywhere (in the kitchen sink) so i have to only slightly turn the cold water tap on, so i suspect the cold water feed is pretty good to the boiler. as for the length of pipe, i dont know, will check this out tonight.

 

[garygrant]

as far as i know, combi boilers are generally slowish to heat the water up, unless you have one of the hi tech modern types that store a small amount for faster delivery. it's just the way they work. if you get too much flow from the hot tap anyway, really really fast, this will also reduce the hot water temperature.

 

[plumAJP]

so would it be better to slowly run my hot water tap or let it run fast?

 

[reneel]

Hi

MY sister has a combi. I prefer the hot water cylinder myself.

running it slower will probably make it a little hotter, but basically won't really improve the time it takes to heat up at the tap. it is just the design of the boiler/pipe run length/flow rate in general.

 

[TicklyT]

Pipe diameter may also have some effect on hot water delivery.

If 22mm or 3/4" pipework from an old hot water system has been re-used, you will have to run off about twice as much cold water held in the pipework as you would from a 15mm pipe run of the same length.