This post is for only those who actually know what a primatic cylinder is!
I have come across one (finally!) It is nicely located within a metre of the boiler having 1" (28mm) gravity flow and returns to one side of the old boiler. (The pumped 22mm heating circuit on the other side of the boiler).
Heating circuits are working fine and a manual air bleed just 100mm away on the pumped flow shows the boiler fully charged with water.
Gravity flow pipe at boiler is hot but no circulation to cylinder primatic heat exchanger and so water in the cylinder is not being heated!
Client reports one day it was working fine, then it just stopped working. Apparently some noise was heard on the last day it worked and probably has something to do with it!
Logically there is either an obstruction in the pipe or some sort of air lock on the gravity primary. Other than the trick of removing the boiler stat and letting it boil for a few moments what else might work?
So what sort of faults do primatics develop and what fixes are available other than ripping it out and fitting a coiled indirect with a F&E tank!
Edit: Hot water (albeit cold at the moment!) is clear and no obvious contamination, so the designed air lock (bubble) would seem to be OK. I need to take another look just in case there is an external vent fitted to the cylinder as I now know some types have this feature.
I have come across one (finally!) It is nicely located within a metre of the boiler having 1" (28mm) gravity flow and returns to one side of the old boiler. (The pumped 22mm heating circuit on the other side of the boiler).
Heating circuits are working fine and a manual air bleed just 100mm away on the pumped flow shows the boiler fully charged with water.
Gravity flow pipe at boiler is hot but no circulation to cylinder primatic heat exchanger and so water in the cylinder is not being heated!
Client reports one day it was working fine, then it just stopped working. Apparently some noise was heard on the last day it worked and probably has something to do with it!
Logically there is either an obstruction in the pipe or some sort of air lock on the gravity primary. Other than the trick of removing the boiler stat and letting it boil for a few moments what else might work?
So what sort of faults do primatics develop and what fixes are available other than ripping it out and fitting a coiled indirect with a F&E tank!
Edit: Hot water (albeit cold at the moment!) is clear and no obvious contamination, so the designed air lock (bubble) would seem to be OK. I need to take another look just in case there is an external vent fitted to the cylinder as I now know some types have this feature.
