atiston Europrisma water heater

[Dave Walker]

evening all
might be a daft question but hopefully all i need is reasurance. i have been asked to move a water heater in a cafe that has been what really should be a walk way so its causing a bit of trouble in its current location. the unit is a undersink unit and the new possion would be a oversink possion. my question is what is the diffrence beetween a under sink and oversink unit is it just the connection points or is there any other reason why i could not fit this over the sink.

 

[lame plumber]

wont look good if its an undersink unit and dont turn it upside down to make the pipework look better

 

[Dave Walker]

dam never thought of turning it upside down.. yes i appreciate it wont look good with the pipework out the top i would get it as neat as possible but it will be out of site and would look a lot better than it does at current i think the original plumber was a bit carless with how he instaled it will try and pop some pics for you to see

 

[jase158]

need to make sure that it hasnt been put there because of the distance from tap!!

these need an expansion vessel or a certain distance to taps or special taps!!

I think the oversink have a built in tap that when the water gets too hot will let the water out the tap.
undersink you have to add taps/ expansion vessel or certain amount of pipework to allow for expansion

 

[Dave Walker]

hi jase158 thanks for your reply i think it was placed in its current location so to give it the min distance to allow for the expansion if i rember wright this needs to be about 2.8 meters if its bellow this then you can buy a expansion kitt for it. the new possion would give me 3.5 meters of pipe to take up the expansion so this part is ok.i just wanted to check really that there was no reall reason why this unit could not be fitted higher other than the conections of it.

 

[Dave Walker]

current location and pipework not how they have put a bin infront of the heater so they dont forget about it when carrying trays in and out past one another. you will also note how moving this heater will allow for the pipework to be tide up especally as its not cliped or supported under the sink

 

[jase158]

i have never seen anything like that but look through the manual
http://www.ukhps.co.uk/pdf/ariston-europrisma-instructions.pdf

 

[Dave Walker]

Just had a look don't say it can't be fitted above so that will do me now I can price the job and sort the mess under the sink etc out for them. Sure I can make it look a lot better than that and easer for them clean round

 

[buckley plumb]

the oversink unit has a swiveling outlet like a tap the undersink unit has to be piped to the hot pipe - if its the 15 litre version it has to follow G3 unvented rules from your pic the unit is fitted with flexis i would not recommend that copper pipe should be used.

 

[buckley plumb]

also cant see epansion vessel or pressure reducing valve 15 litre unit needs them

 

[SimonJohns]

the oversink unit has a swiveling outlet like a tap the undersink unit has to be piped to the hot pipe - if its the 15 litre version it has to follow G3 unvented rules from your pic the unit is fitted with flexis i would not recommend that copper pipe should be used.

Manual says you have to use flexis.

I've never used flexis on one but you should

And I thought under 16l was exempt from g3?

NRV and EV not required depending on pipe length and volume

 

[lbp plg & htg]

Does not apply to 15l or less.

 

[stevetheplumber]

i havent got the instructions to hand but i think if you convert to oversink you have to remove the imersion and reverse it

 

[lbp plg & htg]

i havent got the instructions to hand but i think if you convert to oversink you have to remove the imersion and reverse it

I know that stands with the streamline or at least the old one but not sure about this one though Steve.

 

[buckley plumb]

Manual says you have to use flexis.

I've never used flexis on one but you should

And I thought under 16l was exempt from g3?

NRV and EV not required depending on pipe length and volume

fitted one last month and manual said copper and advised expansion vessel and press red if you not got 4m from unit to tap

 

[buckley plumb]

Ariston Europrisma Installation - YouTube

 

[Dave Walker]

Spoke to ariston tec support today just to check and they said not a problem as long as you don't turn it upside down. Looks like they read the post earlier.

 

[jase158]

Ariston Europrisma Installation - YouTube

that video doesnt show 600mm for pressure relief valve

 

[lbp plg & htg]

Whats the 600mm for?

 

[hammers4spanner]

those plastic couplings are utter utter utter carp on a whole new level of carp

 

[jase158]

maximum of 600mm from outlet to tundish (no tundish in video)
and outlet of tundish should be one size greater then inlet
and the discharge pipe must have a vertical section of pipe at least 300 mmin length, below the tundish before any elbows or bends in the pipe work.

 

[lbp plg & htg]

Thats what threw me - 500mm im sure it should be. The problem is you will never get an answer as to whether its 500mm as the crow flies or 500mm of pipe.

 

[buckley plumb]

depends if its the 10 litre or 15 litre wether it needs tundish or not go onto ariston site and download manual.last time i did unvented was told its now 600mm not 500 as with everything in gas and plumbing no one seems to tell the training centres

 

[jase158]

depends if its the 10 litre or 15 litre wether it needs tundish or not go onto ariston site and download manual.last time i did unvented was told its now 600mm not 500 as with everything in gas and plumbing no one seems to tell the training centres

thats where i got 600mm from, but thats a maximum, so if you are doing 500, then fine
and i looked on the instructions and it is both that needs tundish, otherwise you wont know if its got a problem would you!!