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Posted By Topic: Gas Central Heating

Bangar
Mar 19 2013 14:54


I have a customer who is wanting a power outlet installed for a gas central heating system, they also want some dampers and thermostats wired up.

Question - is there anything in 3000 that excludes the need for RCD protection. For example - single power outlet will be under house, no damp or outside situation, not accessable for general purpose and the customer does not want it to be hard wired.

I take it 2.6.3.2.1 is only for Australia and not applicable here?

Ive also seen earlier posts regarding isolation devices for gas appliances - is there any thing I need to be aware in regards to Gas Regulations when instaling/connecting?

Any help or reference to section much appreciated.
   

Russ
Mar 19 2013 17:09

If no RCDs the hard wire it, currently a permanent connection will do but when the rules change you will need a double pole isolator.

Remember to check your damper type - there are elv dampers around but many are 230v, some are power open spring return and may need an earth, some are power open / power close - luckily all these seem to not require an earth. Depending on the type I run either 1.0mm 2c+e or 1.0mm 3c.
   

pluto
Mar 19 2013 17:26

Bangar Mar 19 2013 14:54

Your comment 1
I have a customer who is wanting a power outlet installed for a gas central heating system, they also want some dampers and thermostats wired up.

Question - is there anything in 3000 that excludes the need for RCD protection. For example - single power outlet will be under house, no damp or outside situation, not accessible for general purpose and the customer does not want it to be hard wired.

My comment 1
if you use a socket outlet for mains connection if MUST be on a RCD; why not use a permanent connection unit then the RCD is NOT required, as it is considered to be fixed wired.

Your comment 2
I take it 2.6.3.2.1 is only for Australia and not applicable here?

My comment 2
2.6.3.2.1 is for Australia only, use for 2.6.3.2.2.New Zealand requirements,

Your comments 3
Ive also seen earlier posts regarding isolation devices for gas appliances - is there any thing I need to be aware in regards to Gas Regulations when installing/connecting?

My comments 3
Refer to new clause 4.18 (in as/nzs 3000 Amendment 2) for the electrical isolation arrangements and clearances from LPG bottles or Reticulated gas supply metering. This new clause is likely to come into force on 1 July 2013 when schedule 2 is updated by amendment 3 of Electrical Safety Regulations. There may be some minor amendments to 4.18 when it is cited on 1 July 2013.

There are currently some amendments being made to the Gas Standard, as/nzs 5601; to align with the new requirements in clause 4.18 of as/nzs 3000.


   

Mike
Mar 20 2013 10:43

Hi there,when this new rule comes in re double pole isolator along side the gas appliance what type of ISO switch can I use next to a gas fire in someone's 2 million dollar house.Any suggestions?
   

pluto
Mar 20 2013 12:06

Mike Mar 20 2013 10:43

Your question
Hi there,when this new rule comes in re double pole isolator along side the gas appliance what type of ISO switch can I use next to a gas fire in someone's 2 million dollar house.Any suggestions?

My reply
The new clause 4.18.1 of the Wiring Rules when mandated (currently expected 1 July 2013 by amendment 3 of the ESR 2010) permits the use of the following:-
a) a plug to a switched socket outlet; or
b) a plug to a socket outlet that may be located in an inaccessible position and has a remote switch in all live conductors (double pole for single phase)in an accessible position; or
c) a switch operating in all live (active and neutral) conductors.

It is being proposed (but not confirmed at this time) for domestic installations only, that the number of poles on the remote switch or the isolating switch only may be amended. Look at the mandating statement in amendment 3 of the ESR 2010 to verify that the proposed change has been adopted.

In the case of the socket outlet in a) above total isolation is obtained by removal of the plug from the switch socket outlet.
   

REN
Mar 20 2013 17:02

Hi Pluto what is the reason behind switching all active conductors? And theoretically a 3 phase heater would need a 4 pole isolator?
   

Mike
Mar 20 2013 17:30

At the moment I cut off the plug on the gas fire and use a PCU not requiring an RCD.So does this mean I will have to fit an RCD to have a socket in behind the fire to meet isolation rule, if I don't use some giant double pole isolator on the outside.That sounds crazy when you are not easily able to isolate without unscrewing fire and pulling it out.Should already be isolated before you pull it out incase you squash a wire.
   

AlecK
Mar 20 2013 19:45

I agree with Mike that isolation should occur before moving the appliance.
Pluto left out the preamble to that new Rule:
" a gas appliance...shall be provided with a mans of electrical isolation that is adjacent to the appliance location and is accessible with the appliance in the installed position.

So a socket behind it won't be OK

And nor will a normal 2-pole 'light' switch (matching the rest of the sockets / switches) alongside , because they are not isolators.


So right now the options for that fire may be limited to something fairly industrial-looking.
Hobs & similar should be fine with a socket. And no need for RCD either if you take advantage of exception 3 - though what's wrong with having this socket on an RCD anyway?


Actually this "new" rule isn't all that new, it's been in the gas code for a long time.
And that's where the "all live" wording came from.
Personally I regard that as excessive, and tried to have it changed but was unsuccessful.
And since it has to be an isolator, changing wording to "all active" won't make it any easier for things like fireplaces to avoid the industrial look.

Have to hope the switch maskers have something suitable in the pipeline, with so many hobs / fires / califonts going into houses these days.
Otherwise a socket alongside will be about the only acceptable option.
   

smith982
Jun 07 2017 00:20

Use a socket outlet as told by Pluto above, and for the last two questions, you need to refer clauses added to arrange electrical isolation and clearances.

Gas Central Heating