Author Topic: Service Clearance  (Read 2335 times)

Offline viking

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Service Clearance
« on: February 12, 2015, 10:36:21 AM »
Have a site with 2 boilers sitting back to back 8" apart. Manufacturers certified installation instructions RECOMMENDS 12" service access to rear of boiler. There is nothing in the back of the boiler that would need serviced, so i don't see the 8" being a problem other than it doesn't meet manufacturers recommendations.
This is a discussion we are having at work.
Any thoughts? Any code clauses that might apply? I've looked at accessibility(4.14), Boilers(7.1) and 4.1.3 (appliance shall be installed in accordance with manufactures certified instructions)
I guess it comes down to the word RECOMMEND?

What do we think?

Thanks Mike

Offline Admin

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Re: Service Clearance
« Reply #1 on: February 13, 2015, 07:15:44 AM »
I agree.  It comes down to a recommendation versus a mandatory requirement.

Section 1.6 of the Gas Code says,

Quote
1.6 - In this Code, unless approved otherwise by the authority having jurisdiction, “shall” indicates a mandatory requirement; “should” indicates a recommendation or that which is advised but not mandatory; and “may” indicates an advisory or optional statement. Notes to the text do not include mandatory or alternative requirements. The purpose of a note is to separate from the text explanatory or informative material that is not properly a part of this Code. Notes to figures and tables, however, are considered part of the figure or table and may be written as mandatory requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.

If the instructions say a 12" clearance should be maintained, or a 12" clearance is recommended then having only 8" would not be an infraction in your case.

If the boiler was installed near combustible material we would follow Clause 7.1.3 and would need 18" clearance to the rear.  The second boiler would not be considered to be combustible material.

Quote
Clause 7.1.3 - Except where permitted by Clause 4.13.2, a boiler shall be installed with the following minimum clearances from combustible material:
(a) vertical — 18 in (450 mm);
(b) sides and rear — 18 in (450 mm); and
(c) front — 48 in (1200 mm).
See also Clause 4.14.2.

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Clause 4.13.2 - The clearances to combustible material specified in Clause 7 shall not be reduced unless
(a) such reduced clearance is certified as safe by a nationally recognized certification organization
acceptable to the authority having jurisdiction, and so marked on the appliance nameplate; or
(b) protection is provided for the combustible material, and such protection and such reduced clearance
are in accordance with Table 4.1.

Quote
Clause 4.14.2 - An appliance shall be installed with a minimum service clearance of 24 in (600 mm) to any side, top, or bottom where service could be necessary, except where
(a) a greater distance is indicated on the appliance rating plate; or
(b) the distance is not sufficient for the removal, replacement, or repair of a component, an accessory,
or any equipment either forming an integral part of the appliance or connected to the appliance, in which case minimum service clearance that is adequate to effect such removal, replacement, or repair shall be provided.
All measurements shall be taken between the outermost projection of the appliance and surrounding structure or property line after the appliance has been installed.

Clause 4.14.2 does not mention the rear of an appliance but some people might interpret the word side to include the rear, in which case a 24" clearance would be required.  I personally would not enforce this Clause in your example, but I could see how others would.

Offline viking

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Re: Service Clearance
« Reply #2 on: February 13, 2015, 08:48:29 AM »
Thanks.
I believe your quote from 1.6 says what I was looking for.
4.14.2 says 24" clearance where service could be necessary. Since there is no service required at the rear I don't think it applies.

Same site new question.
I believe we have multiple boilers (allover 400,000) on a single circuit breaker. I know I have read in the electrical code they need to be on dedicated circuits but now I can't find it.
Any Idea?


Offline Porcupinepuffer

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Re: Service Clearance
« Reply #3 on: February 13, 2015, 01:06:03 PM »
Module 5 of the G3 training modules on page 25 shows "26-808 Heating equipment rated at more than 117kw"



Offline viking

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Re: Service Clearance
« Reply #4 on: February 13, 2015, 03:28:07 PM »
Thanks Porcupine. That's what I was looking for.