Over 3 mins to get hot water in kitchen - is this normal?

[ShaunCorbs]

Do you know which section of building regs your quote came from so that I can refer to it. It does say it is only a recommendation though.

I had instructed private building control for my renovation project but the surveyor for some reason is not replying to my e-mails about this issue as I had asked him first whether 3+mins was normal before posting here.

3.7 g3

"Pipework should be designed and installed in such a way as to minimise the transfer time between the hot water storage system and hot water outlets."

also

4.4.1

"In small systems, with normal tap running times and a maximum delay of 30 seconds for the hot water to reach the outlet, the pipes would be subjected to sufficient temperature to kill Legionella (or inhibit growth) without the need of secondary circulation."

but something is wrong

 

[LCV]

Thank you Shaun. I presume my house despite being on 4 floors is still classified as a small system.

 

[ShaunCorbs]

Thank you Shaun. I presume my house despite being on 4 floors is still classified as a small system.

yes was from my commercial book

could you measure how much water is drawn off before it becomes hot please?

 

[ShaunCorbs]

if my math is right a bristan kitchen/ any tap has a flow rate of about 10-15 lpm (estimated)

so take it at 10 and you dont have hot water for about 3 mins

thats 30L does that sound about right (ballpark)

 

[LCV]

I can fill my kitchen sink to the top before it gets hot. Would the measurement of my sink be sufficient?

 

[ShaunCorbs]

I can fill my kitchen sink to the top before it gets hot. Would the measurement of my sink be sufficient?

need to know how many l your sink holds you could try with 1 or 2 L bottle of pop and see how many it takes before you get hot water

 

[LCV]

Do you feel like there is something else wrong aside from not having the secondary return? I don't know why but something is not sitting right with the length of time the taps in my house is taking. My neighbour across the road lives in a very similar house but his combi boiler is located on the 3rd floor and he doesn't have to wait minutes to get hot water to his kitchen.

Actually, just thinking about this a bit more. I have another neighbour who lives in an identical house (these are new houses 11 years old on a new street so all the houses are built the same size and layout). He had a loft conversion but did not change his combi boiler. I am going to ask him to time how long it takes to get hot water in his loft.

 

[LCV]

Ah okay. I will do that tomorrow and post back. Thanks you so much and goodnight.

 

[ShaunCorbs]

Do you feel like there is something else wrong aside from not having the secondary return? I don't know why but something is not sitting right with the length of time the taps in my house is taking. My neighbour across the road lives in a very similar house but his combi boiler is located on the 3rd floor and he doesn't have to wait minutes to get hot water to his kitchen.

Actually, just thinking about this a bit more. I have another neighbour who lives in an identical house (these are new houses 11 years old on a new street so all the houses are built the same size and layout). He had a loft conversion but did not change his combi boiler. I am going to ask him to time how long it takes to get hot water in his loft.

like i have said before factors on a few things like pipe runs/ length, is it insulated, dia of pipe work etc

tbh i would of put a secondary return in anyway as while your doing the lot its one extra pipe that can matter

and good night

 

[LCV]

Oh okay. I understand. It is difficult to make a real assessment without all the relevant information.