No hot water

[ro63rto]

small update.

had to change the thermostat in the HWC as I had a small earthquake the other morning. the immersion heater did not stop at the preset 60°c and boiled it. ended up with it venting into loft tank. scared the bejeezus out of me.

now have a new RDT re-settable thermostat working.

this in turn has allowed the boiler to fire up when HW is selected from the programmer. however it switches off after 5 mins.

the flow connection to HWC is too tight to get any tools to so I tried further up the vent pipe (right side on photo) and only got water not air.

could it be sludge in coil and if so, how to get rid?

 

[Hugh Jaleak]

Did warn what might happen if the immersion boils the cylinder! Immersion sorted now so no need to worry there. If coil is blocked then may need to remove cylinder and flush coil out with a hose. Unsure if a chemical cleaner will do much especially as there is no circulation. Once this is sorted a chemical clean will do no harm, and put some inhibitor in when clean is done.

 

[ro63rto]

Did warn what might happen if the immersion boils the cylinder! Immersion sorted now so no need to worry there. If coil is blocked then may need to remove cylinder and flush coil out with a hose. Unsure if a chemical cleaner will do much especially as there is no circulation. Once this is sorted a chemical clean will do no harm, and put some inhibitor in when clean is done.

Yup, you did. Never told me it would be that loud though

Not looking forward to removing HWC but at least I'll get to see what all the extra pipes are for. There are 3 open ended ones and 3 with isolation valves.

Defo on the clean and inhibitor. Parents can't remember last time it was done.

Thanks

 

[Hugh Jaleak]

Least you didnt get a boiling waterfall.....

If you want a rough guide to what pipe does what need some more pics please. Should only be 4 (possibly 5 if shower or secondary return fitted) connected to cylinder to disconnect to remove it. Vent/hot feed to taps at the top, cold feed in at the bottom and the flow and return from boiler to coil.