On 19 Aug, 17:44, "Heliotrope Smith" wrote:
wrote in message

...

I have a wood burning stove with back boiler. Its quite difficult to
access the loft/feeder tank, so I would like to use the Screwfix
Concentrate(No nonences) additive. This comes in a sealant like tube,
with a small kit. is it just a case of attaching this to the stopcock
on the bottom of the boiler, opening and filling. Does the water go
everywhere? How much to use? does it block drain for future?. ANY help
advice/tips would be appreciated.?
Thanks

If by stopcock you mean the drain cock with a 1/2" hose connection then
leave it well alone.

Not only would not get a good connection to this but there is a very good
chance that once opened the washer will disintegrate and you will have to
drain the system to replace it.

I am not familiar with the screwfix kit but probably contains fittings to
inject through a radiator vent pin or 1/2" rad vent plug.

No need to drain anything off. *Turn off both rad valves and connect up so
that everything is watertight before opening one rad valve. Pump in the
whole tube and switch off the rad valve again. Take off the filling kit and
put back pin/plug.

Job done, no mess or leaks.

(well hardly any)

Yup, it is as simple as that.

Although you should leave one rad valve open when you inject the
chemical to allow air to escape.

To the OP: Why not get something from Sentinel or Fernox?