One of those customers

[pakmei]

Hi all, I need a bit of help, I have a customer who has a 210l santon, he runs his DHW on constant. He tells me that he believes that once the cylinder has reached temp his boiler should not need to fire again until he draws off some hot water, even if he goes on a weeks holiday. I see on the santon litereture that expected heat loss is 1.7kwh how can I equate this to degrees dropped per hour, so as to explain this to him in lay mans terms

 

[SimonJohns]

You need to find out the specific heat of water. This will tell you how many degrees you will lose

 

[pakmei]

the water is heated to 60 degrees does this help

 

[PlumBum86]

How the hell does he expect water to stay hot for a week without being heated? I dont know the maths on this but, basicly the water will loose its heat due to heat exchange.. If the cylinder temp is 60 degrees and the room tempreature is 20 then eventually the two tempreatures will balance out. Like hot coffee in a themas flask or a warm drink in the fridge.

 

[pakmei]

How the hell does he expect water to stay hot for a week without being heated? I dont know the maths on this but, basicly the water will loose its heat due to heat exchange.. If the cylinder temp is 60 degrees and the room tempreature is 20 then eventually the two tempreatures will balance out. Like hot coffee in a themas flask or a warm drink in the fridge.

I don't know he's a real gem, he rang my office again yesterday complaining that even though he hadn't used his hot water for two hours the boiler had just come on, well it's going too isn't it.
Anyway the only stats that Heatrae can supply are that his cylinder will require 1.7 kwh in 24 hours to maintain tempereture so i'm off to see him tomorrow to attempt once again to explain the workings of his system

 

[Plumbstar Tom]

is he paying for this visit?

 

[pakmei]

is he paying for this visit?

ha ha ha ha ha ha no national house builders see it as your duty to pander to there customers every whim and in times of recession they tend to have you by the painfull bits

 

[Plumbstar Tom]

ahh, didnt know it was a new build

make sure you talk to him slllllloooooooowwwwwwllllllllyyyyyyyy

 

[ADM360]

hi, with my basic grasp of maths, the specific heat of water and all things inbetween I think and please don't quote me on this!! that a 1.7kwh heat loss over 24 hours would equate to aproximatly 29.14deg a day or 1.24 deg per hour, but don't forget the additional heat losses though pipe work and the effect of gavity circulation though pipework (poorly installed hot pipe work from the cylinder could result in gravity ciculation which can waste all the hot water in the cylinder!), oh and don't forget the drippy hot tap!! don't know if this will help you best of luck with it though, don't forget that the only thing the customer will have heard and retained from any conversations with you/ builder and santon is the great insulation values and the minimal heat losses from the cylinder!!

and so to bed!!

 

[Dannypipe]

Your customer has waaaaay to much spare time. Is he retired by any chance? Probably best to remind him that you arent, and what goes up must come down.