what flow ratio is this water heater

[muckington]

The cheapest one screwfix sell. it says its a hand wash

https://www.screwfix.com/p/triton-t30i-instaflow-handwash-oversink-water-heater-3kw/556hp#product_additional_details_container

But they do not list its flow ration?

 

[Harry Bloomfield]

The cheapest one screwfix sell. it says its a hand wash
https://www.screwfix.com/p/triton-t30i-instaflow-handwash-oversink-water-heater-3kw/556hp#product_additional_details_container But they do not list its flow ration?

It's an instant water heater, the flow depends upon how hot you need the water, and how cold the incoming water is.

 

[Johntheo5]

Its a 3kw heater and may be limited to a max temperature of 48C like its electric shower cousin.

Assume a normal required temperature of say, 40C, then...
From 5C (debths of winter) 1.23LPM
From 10C 1.43LPM
From 15C 1.72LPM
From 20C (high summer) 2.15LPM

If you want to calculate your own flowrates, then

LPM = 43/(RequiredHotTemp-MainsTemp)

 

[muckington]

It's an instant water heater, the flow depends upon how hot you need the water, and how cold the incoming water is.

Sorry let me rephrase it. "What is the flow ratio with maximum heat"

 

[muckington]

Its a 3kw heater and may be limited to a max temperature of 48C like its electric shower cousin.

Assume a normal required temperature of say, 40C, then...
From 5C (debths of winter) 1.23LPM
From 10C 1.43LPM
From 15C 1.72LPM
From 20C (high summer) 2.15LPM

If you want to calculate your own flowrates, then

LPM = 43/(RequiredHotTemp-MainsTemp)

Good guide that you have there of winter 1.23lpm and summer 2.15mpm

But are you sure about its maximum temperature of 48C. Do we need 56C ish to kill bacteria? is it not SOLD AS a "hand wash". Looking at a Health and Hygiene point of view that is

 

[Harry Bloomfield]

But are you sure about its maximum temperature of 48C. Do we need 56C ish to kill bacteria? is it not SOLD AS a "hand wash". Looking at a Health and Hygiene point of view that is

It's limited to 48C, to avoid scalding. Basically, you just have a tap on the unit, the more you turn it on, the faster the flow, the cooler it will be. The slower the flow, the hotter it becomes. If you turn the flow down too far, it will cut itself off, to avoid you being scalded.

No, you do not need 56C to kill bacteria. The cold water mains, is absolutely safe, in that respect, providing it has not been stored locally. Only water which has been stored in a tank, or cistern, needs to be heated to >56C, to kill off any bacteria, Legionella. Usually, they call it 60C, to ensure the entire amount of water is above 56C.

 

[Johntheo5]

I've often wondered about electric showers with their own internal pump that are fed from a CWSC which is regularly at 20C+, but the shower, for obvious reasons, cannot be run at temperatures higher than 48C, and its TCO will kill the power to it at 48C. A 9kw shower has ~ a 230ml heating can so the residence HW time, assuming a flowrate of 4.3LPM when heating from 10C to 40C, is only 3.2sec, maybe this residence time is enough to kill any nasty germs as they will be in contact with very very hot 9kw heating elements in this very small heating can. Also, especially with the advent, of ASHPs, more and more unvented HW cylinders are now being run with storage temperatures down to 45C or even lower, and are supposed to be heated to 60C weekly? for legionella protection, but how many follow this advice, and just wonder will the instances of legionella slowly rise with the rise in ASHPs?, hopefully, not.