DHWC replacement

[Leoki]

When replacing a DHWC (vented/indrect system), as well as draining the cylinder itself (there is an accesible drain cock) would it be enough to just drain down the central heating system to below the level of the cylinder rather than empty the entire system ?

The cylinder sits in an airing cupboard on the landing and is in a raised position so if i drain from a low point in the system would i take enough water out of the primary flow and return pipework to the cylinder to be able to de-couple the pipework from the cylinder ?

Also the cylinder is 900 x 450, about 117 litres i think. When you buy a replacement cylinder of the same dimensions, when it is placed onto its base, would the flow and return tappings on the new cylinder be in the same position as those on the original cyclinder ?


🙂

 

[Puddle]

Well you could just drain top half of system if cylinder in that section, open vents of all top rads as well however by part draining systems you can cause problems when refilling. Air locks ect

You can get the same size cylinder however if you are replacing a old cylinder obviously the new cylinders come pre lagged and that has to be taken into consideration

It again depends on the age of the cylinder you are replacing or if you can get same make however generally the tapings for flow and return will be different on at least one connection, so you are going to have to alter the pipework as required

The cold feed could also require altering slightly however hot supply should be Ok if you fit in exact location as old cylinder, but because of pre lagging this to may require slight alteration

imho

 

[Dotty]

Puts me in mind of one of my first jobs when I moved over here in Northern Ireland.

Old boy wanted me to replace his cylinder so i went and got him a nice new foam lagged baby and dropped it off to him ready for me to fit at the weekend.

Anyway he rings me on the Friday.

"That tank must be good, took me ages getting the packing off."

"What packing? There was no pa.......**sound of penny** Oh you didn't!"

He had.

I treated him to a new wrap round jacket for the laugh he gave me!