Potterton Performa 28 - No Hot Water

Hi,

I have a Potterton Performa 28 Boiler and the central heating works perfectly, a couple days ago the hot water stopped so after trying a reset, checking the controls to make sure its turned on etc we thought it could be an air lock as the water was running through it but it was cold.

This did the job for the first day but its done the same thing again and trying to clear it didnt help this time. Any ideas what could be causing this? The pressure on the front of the boiler is exactly where it should be.

Thanks
Pete

If it is just the 28 then it is the large DHW diaphragm housed on the front of the diverter valve.

If it is the 28i then it will be the small dhw diaphragm to the left of the gas valve.

I think its just the 28, it doesnt have the electronic error code display on the timer etc.. by the way, no lights are flashing to say it has an error either.......

when you turn hot water tap on is tap symbol lighting up >????

Hello
do you have lots of flow on hot water tap but not getting hot or gets hot then goes warm
does the boiler DHW temp lights go all the way to 70 deg
and the boiler burner keeps cutting in and out.
Is your heating working perfectly ok

Then you have %100 got a blocked DHW heat exchanger.
simple job
£50 off ebay for the exchanger with seals, if you get one make sure seals
are not just O rings but a proper rubber seal about 1/4 inch thick
"1- 1/8 outside diameter you will need 4 off these. I had the wrong seals sent so i had to re use the old ones, I cleaned them put a bit of Vaseline on them and they are fine but i reccomend new seals.

There are 2 x screws holding heat exchanger in place just undo these bolts and the exchanger is now loose, remove heat exchanger being careful not to catch any wires on the way out.
Remove seals from their locations on the back of the brass valves and replace with the new ones, then refit new exchanger.

Forgot to mention first of all,
isolate cold water in by turning valve under boiler
isolate heating flow and return by turning valves under boiler
now drain boiler by attaching hose to drain tap on right of boiler.
when finished close drain valve
turn on heating flow and return
turn on cold water
re-charge system to approx 1.5 bar
bleed pump with little screw on top of pump

BE CAREFUL NOT TO GET ANY WATER IN CONTROL BOARD
LIKE I DID AS THIS PLAYS HAVOC WHEN YOU TRY TO RUN BOILER AFTER REPAIR. IF YOU THINK YOU MAY HAVE GOT ANY WATER IN BOARD
DRY OUT WITH HAIR DRYER AND IT SHOULD BE FINE.

I did replace my diverter valve at the same time, this does make replacing heat exchanger easier as you have more rome to remove it. £80 of ebay
so for £130 my boiler is like a new boiler.

HOPES THIS INFO HELPS A FELLOW DIY'ER

why replace the plate when it can be cleaned????? plus what did you do to stop it sludging up again???

Paul

Theres always some smart arse
I put inhibitor in the system
also if you think soaking them in limescale remover or the like is any good think again, believe me it doesnt get it all out thus reducing efficiency.

For your info i put the old one in a sonic bath then cut it in half
even a sonic bath left it partially clogged up.

so its a new one for me anyday £50 not the end of the world is it on a 7 year old boiler thats had nothing spemt on it in all that time.

Hi all

I have the same issue as the OP, hot water for a short while and then cold and so on.

I purchased a new DHW and seals but how the hell do get to it? It's at the back behind everything?

Also sorry to resurrect this old post but it is exactly what my issue is and I'm hoping all the helpful people that got involved can help me too!!

you need to start your own post , dont hijack an existing one you wont get the correct replies