Ideal ICOS PCB - Worrying!

[Boilerman2]

I'm SURE THEY ARE LOOKING FORWARD TO YOUR CALL

 

[gdallas]

I'm SURE THEY ARE LOOKING FORWARD TO YOUR CALL

lets wait and see.... PCB + Fan still workin by the way!

 

[gdallas]

I'm SURE THEY ARE LOOKING FORWARD TO YOUR CALL

also, Boilerman2... how old are you? just a random Q.

 

[OLLIE20]

If you put a 13 amp fuse in on a system/ conventional boiler then you get say a short circut on the pump it can (depending on how things are wired) blow the programmer before the 13 amp fuse goes and then trip the main MCB on consumer unit, which then means your programmer is fooked,and you now need a new programmer aswell as pump coz some t**t fitted a 13 amp fuse, always 3 amp unless literature to say otherwise,especially where external controls are involved

 

[gdallas]

If you put a 13 amp fuse in on a system/ conventional boiler then you get say a short circut on the pump it can (depending on how things are wired) blow the programmer before the 13 amp fuse goes and then trip the main MCB on consumer unit, which then means your programmer is fooked,and you now need a new programmer aswell as pump coz some t**t fitted a 13 amp fuse, always 3 amp unless literature to say otherwise,especially where external controls are involved

i mean this in the nicest of ways, but that just reinforces how much you dont understand the electrical side of your boilers

if you got a fault on the pump (provding fuses are dsciriminating) then you want the upstream fuse to blow first, i.e. the 3A in the PCB.... if you got a fault up stream of the PCB, then you would want that fuse to blow, i.e the spur!

 

[DP]

Point you seem to be overlooking is that the programmer will be between 3.15 and 13 amp fuse. 3.15 will not be effected as fault will be before that and 13 amp will not disconnetc at programmer trac (rated at max 5amp) will have evaporated.

Just because you cable is rated at 16amp, spur does not need to be fitted with a 13amp fuse.

32 ELECTRICAL CONNECTIONS
Wiring should be 3 core PVC insulated cable, not less than
0.75 mm2 (24 x 0.2mm), and to BS 6500 Table 16. For IE
reference should be made to the current ETCI rules for
electrical installations.
Connection must be made in a way that allows complete
isolation of the electrical supply such as a double pole
switch having a 3mm (1/8") contact separation in both
poles, or a plug and socket, serving only the boiler and
system controls. The means of isolation must be
accessible to the user after installation.
WARNING. This appliance MUST be earthed.
A mains supply of 230 V ~ 50 Hz is required.
The fuse rating should be 3A. All external controls and wiring
must be suitable for mains voltage.
Wiring external to the boiler MUST be in accordance with the
current I.E.E. (BS.7671) Wiring Regulations and any local
regulations.

 

[gdallas]

Point you seem to be overlooking is that the programmer will be between 3.15 and 13 amp fuse. 3.15 will not be effected as fault will be before that and 13 amp will not disconnetc at programmer trac (rated at max 5amp) will have evaporated.

actually... you might be on to something! this could possibly be the reasone for the 3A spur......

Cheers DP

 

[OLLIE20]

If you put a 13 amp fuse in on a system/ conventional boiler then you get say a short circut on the pump it can (depending on how things are wired) blow the programmer before the 13 amp fuse goes and then trip the main MCB on consumer unit, which then means your programmer is fooked,and you now need a new programmer aswell as pump coz some t**t fitted a 13 amp fuse, always 3 amp unless literature to say otherwise,especially where external controls are involved

i mean this in the nicest of ways, but that just reinforces how much you dont understand the electrical side of your boilers

if you got a fault on the pump (provding fuses are dsciriminating) then you want the upstream fuse to blow first, i.e. the 3A in the PCB.... if you got a fault up stream of the PCB, then you would want that fuse to blow, i.e the spur!

I think it goes to show and i mean this in the nicest of ways, how little you know about CH and its WIRING, a fuse on a PCB will not protect any external components on a system/conventional boiler, youre hard work man, seriously jesus

 

[OLLIE20]

Point you seem to be overlooking is that the programmer will be between 3.15 and 13 amp fuse. 3.15 will not be effected as fault will be before that and 13 amp will not disconnetc at programmer trac (rated at max 5amp) will have evaporated.

actually... you might be on to something! this could possibly be the reasone for the 3A spur......

Cheers DP

HALLELUYA, THE NAIL HAS BEEN HIT ON THE HEAD

 

[Temprise]

The fuse in the fused spur should be 3 amp. 5 and 13 amp fuses are the wrong size.

Temprise, what would you do if you had a 5amp fuse and not a 3 amp. Would you leave the 13 amp in place because you feel 5amp is not to be fitted? Better a 5 amp than 13 amp that will turn the PCB into a 3 bar fire.

Sorry for the late reply to this.

I am not an electrician for the record..

IMO, for whats its worth.

For as long as i can remember going right back to my apprenticeship it was always a 3 AMP fuse req in the fused spur or plug that acted as the isolation for the boiler and wiring and controls associated with a central heating system. Anything else was wrong, it shouldnt be bigger ( 5 or 13 AMP).

British gas, on their contracts check the fuse on every service visit and check this. A 3 AMP fuse is always fitted if it is wrong.

Any manufacturers traing i have ever done, advises the same thing.

I am 80% sure i have been asked this question during an ACS retake and the correct answer was 3 AMP.

Regards.

 

[nickso]

unless it requires a 5A fuse of course.

 

[Boilerman2]

gdallas - a Combustion engineer
NEVER reveals his age only to say i've been in this industry for Thirty Severa years now and have ALWAYS fitted 3a fuses to Gas fired systems and 5a fuses to Oil fired systems (due to slighty higher electical load of burner motor)

 

[Corgigrouch]

Gdallas.... I'd almost forgotten about this post. You are of course right that the fuse in the FCU is to protect the wiring that runs to the boiler and so it would be fine to have a 13amp fuse provided the cable supplying the boiler is of suitable size..... Well, this would be fine if there was a fuse that would protect the wiring of the boiler as soon as the cable sizing reduced to the size of wire used by Ideal.... But there isn't, the only fuse inside the boiler is in the PCB.... So what protects the wiring between the connections and the PCB?

Perhaps this is why Ideal require the FCU controling the boiler to have a 3 amp fuse?

Some boilers do have a fuse immediately on the supply connection and so your argument would then be valid but I believe not in this case. I'm a little surprised that you feel it fine for the wiring between the connection and the PCB not to be suitably protected when the manufacturer EXPRESSLY requires it.

Of course, if I was a clever engineer, then I too would be looking forward to a Winter with an Ideal boiler...

 

[vulcancontinental]

I definitely am not an electrician and am not Part P but used to wire up all my own systems.

I'd just like to know how an arrangement with a

3amp fuse at the unswitched socket and plug (I used that as when the system is disconnected it stays disconnected)

a Boulter boiler with a 5 amp fuse,

an AQ6000 control box with a 2 amp fuse

can burn out one of three 10amp rated relays in the AQ6000 box.

When the board was changed all appliances worked OK for the next 5 years so it wasn't one of them.

Honeywell wouldn't stand up for it as they put it down to voltage fluctuation.

One of their technical people, John Kipping I think, told me that when supplies were monitored in Slough voltages in domestic dwellings often were recorded over 1000V - too bad for my customer.

Any explanation?

 

[ban-all-sheds]

How are gas boilers installed in countries where fused spurs or fused plugs are simply unavailable, and the circuits are 16A?