Sadistic water heater

[JohnD]

Our local hall has a big Heatrae Sadia water heater, about 2 metres tall, and about 15 years old. It seems to be permanently switched on. We are in a very hard water area.

It has taken to foghorning sometimes after hot water has been drawn. No doubt it has a float valve in the vessel on the top. It has been positioned six inches from the ceiling, with the inlet in the exact corner. I have not yet tried to peer into it.

It looks to me like it needs a gymnast with 18" long fingers to change the valve. Any helpful suggestions?

The water is also scalding, is it going to be equally difficult to change the stat in the imnmersion heater?

 

[doitall]

Should have a blender on the outlets.

 

[JohnD]

well it hasn't. Why can't it just be set to non-scalding? It is more than big enough.

It supplies a three basins in the WCs, one in the bar, and a sink in the cleaner's cupboard.

Round here, they supply all cold taps off the mains, and there is no cold-water cistern.

Any other ideas?

 

[Nige F]

The water is also scalding, is it going to be equally difficult to change the stat in the imnmersion heater?

Realistically no because they are usually @ the bottom facing up - BUT you`ll need part P and a 10 page risk assesment at least Just get BG to run gas into the building and fit a gas one

 

[Boilerman2]

Sounds like a Flat back heater Heatrae Sadia type FBM

if the heater has been fitted too close to the ceiling to enable the ball valve to be removed (the probable culprit for the noise) then you will either have to a) cut a hole in the ceiling above the heater or
b) drain the heater down and lift it off the wall (heavy)
I would go with option a) you can make good afterwards with a piece of masterboard whch if cut bigger than the hole can simply be screwed to the ceilg and removed next time there is a problem

to adjust the thermostat, TURN OFF the power, remove the 4 screws holding the bottom cover this will reveal the heating element and thermostats there may be two one is Overheat the other is adjustable

However ACOP L8 requires water to be heated to at least 60'c to combat legionella bacteria, so as already been said in a PUBLIC BUILDING point of use TMV's should be fitted at ALL OUTLETS

there are many many village halls out there that are completely ignorant of their obligations under WRAS which is very very worrying!

 

[JohnD]

I wouldn't call it flat backed, it is cylindrical, but fitted in a corner.

thanks for the suggs

is 60 degrees to kill it? I thought I heard that at 50 degrees it will not grow?

I can't see how to blend mains cold and tank hot, presumably you have to do it at each tap? they are all just single pillar taps, one hot, one cold, at each basin.

 

[Boilerman2]

I sugest you read up on the L8 document a MINIMUM of 60'c is recommended it is possible to fit TMV's on diffrent pressures one per hot tap make sure you fit non-treturn valves adjacent to stop back flow

if you can post a picture of the water heter i might be able t advise you further

 

[JohnD]

here we are

View media item 42782
View media item 42783
View media item 42784

 

[Boilerman2]

That is not an FBM type, I can't remembr the model no for that one but it is a copy of a Fortic type cylinder, with a built in header tank,
the immersion heater is on the side of the cylinder usually under a plastic cover, the thermostat will be there

 

[doitall]

It looks like the wall was built after the cylinder was fitted

Maybe a demolition job.