Central Heating Blowing Fuses

[Davey]

Help Please!

We have the following HW/CH system:

Baxi boiler - 60-0F
3 way valve - ACL 22MM
Timer - ACL LP241
Wallstat - ACL TS142
Tankstat - ACL HTS2

A week ago the 3 amp fuse in the FCU blew and all went dead. I changed the fuse and all was well for a day or so until it blew again.

The wallstat is in the hall and we have been stripping the wallpaper there in preparation for redecorating. Thinking some dirt may have got in the stat we changed this for a new one - Sunvic TLX4104 (SWMBO wanted a nice new one anyway as the ACL didn't fit in with her decor ideas ).

All was well until the following day when the fuse blew again.

Getting desperate we called in the Corgi guy who fitted a new fuse. We explained the problem and (of course) everything was fine when he was there. He did however suspect the pump and replaced this with a new one.

That was yesterday....

This morning everything was working fine. However I came home from work this evening and the fuse has gone again

Can anybody help....please!!!

 

[Softus]

Check the wiring within the boiler casing.

 

[Davey]

Do you mean where the cable goes into the boiler?

Ok I'll try and have a look tonight and make sure any connections are tight and the cable is not damaged.

Thanks for your help.

 

[namsag]

Have a look at pump valves etc around the motorised valve and make sure they are not weeping and dripping into it or into pump itself

 

[Davey]

Sorry to bring this up again.

I checked all the connections as advised and managed to get a fraction of a turn on one or two of them. There was also no sign of any leaks.

Everything has been okay for the last 4 weeks but this morning the g/f clicked the button on the timer to bring the c/h on and there was a bang from the 3 port valve which blew the fuse again.

Does it seem logical that the 3 port valve is causing the problem?

It's an ACL Lifestyle 22mm 679H340 30L0.

Is it likely to be just the motor that has gone or would I be best changing the complete thing?

I gather that on the later ones it is possible to just change the head but ours seems to be an old one (there is a sticker on it saying the warranty expired Jan 95!).

I assume that means the system needs draining down?

 

[seco services]

i would say the board has gone on the valve.

 

[bellairaphon]

yeah check the 3 port valve not saying it is but i came to a boiler doing the same thing swapped fuse works fine then had a quick check everything seemed ok on the wiring side. got called bk ( local council engineer by the way ) same problem turned out to be the switch as when i selected the heating on the programmer the boiler live switch was fluctuating then the fuse went change the valve all fine. so try that

 

[Davey]

Thanks for you help Seco

It's never easy is it

If I'm changing the whole valve does the replacement need to be an ACL or will any make do - are some makes more reliable than others?

Does the wiring use standard colours (on the existing valve its green/yellow, blue, grey, white and orange) or is that too much to ask?

 

[bellairaphon]

same colour earth green yellow) white ( heating on ) grey (hot water off ) orange (boiler pump) blue (nuetral)

 

[seco services]

i prefer honeywell if your changing complete valve and colours are the same.

 

[Davey]

Thank you


Guess what I'm doing tomorrow

Never mind - better than going Christmas shopping!


Davey

 

[seco services]

Thank you


Guess what I'm doing tomorrow

Never mind - better than going Christmas shopping!


Davey

to right.

 

[Davey]

Sorry Guys - back again!

Changed the 3port valve, bled radiators and switched on.

Problem is the boiler fires up for only a few seconds and then goes back to pilot. The pump is running but it seems to be making a funny noise - certainly louder then before.

When I call for C/H, H/W or both the indictor on the 3 port is moving appropriately so I'm confident that is wired ok.

Any suggestions please - Been on it all day and got G/F and pan lids moaning about howcold they are

 

[seco services]

bleed the pump remove centre screw, do it with pump off.

alday what you re plumbed the house.

 

[Davey]

bleed the pump remove centre screw, do it with pump off.

Pump bled and - touch wood - everything seems to be working ok
Off for a well earned pint - will report back tomorrow.

alday what you re plumbed the house.

Yes - but that includes lots of head scratching sessions wondering wtf to do next


Thanks very much for your help.

G/F and kids think you're great