Author Topic: No return air plenum. Gastite direct contact with ducting  (Read 366 times)

Offline RYOUNVS

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No return air plenum. Gastite direct contact with ducting
« on: November 18, 2016, 12:50:51 PM »
Hey all,

I'm a G3 gas fitter in Ontario. I just installed a system including furnace, A/C, duct and gasline. Union Gas came and did an inspection before they would unlock the meter. They have refused to turn on the gas because 1. I haven't installed the return air plenum, it is just the filter rack and filter attached to the side of the furnace. and 2. They are saying that Yellow CSST (Gastite) can't be in direct contact with ducting.

Here is my question: Is is true that I can't have just a filter rack and filter? I plan to get to it in the next week, but wanted to get these people heat. Also, I fastened a piece of drive cleat to the bottom of the floor joist and then fastened it to the side of the furnace so I could have something solid to tie the gastite to on the way down. In my opinion, I am not fastened to the duct system.

Thoughts? Opinions?

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Re: No return air plenum. Gastite direct contact with ducting
« Reply #1 on: November 18, 2016, 01:32:04 PM »
I'm not sure if Union Gas will do construction heat unlocks.  Enbridge does that and will activate the furnace and then come back for their final inspection.  You may have been better off calling it in as a construction heat unlock.

The B149.10 Clause 7.13.5 says,

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7.13.5 - A furnace that is used to heat a residence under construction shall be
(a) installed
(i) on a finished concrete floor;
(ii) on a poured concrete slab that is at least
(1) 4 in (100 mm) thick;
(2) 1 in (25 mm) in height above the height of the basement floor when complete; and
(3) 6 in (150 mm) longer and wider than the base of the furnace; or
(iii) by suspending it in a safe manner;
(b) piped in accordance with Clause 6;
(c) vented in accordance with Clause 8;
(d) fitted with a warm-air plenum and a return-air plenum, both of which are protected against an influx of waste or discarded material; and
(e) provided with a thermostat that is installed on a solid bracket or wall and located in the furnace area or a location supplied with heat through ductwork from the furnace.

The Lennox EL195 installation manual is pretty clear.  Even for construction heat use, the return air duct must be provided and sealed to the furnace.

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EL195UHE units may be used for heating of buildings or structures under construction, if the following conditions are met:
The vent system must be permanently installed per these installation instructions.
A room thermostat must control the furnace. The use of fixed jumpers that will provide continuous heating is not allowed.
The return air duct must be provided and sealed to the furnace.
Return air temperature range between 60°F (16°C) and 80°F (27°C) must be maintained.
Air filters must be installed in the system and must be maintained during construction.
Air filters must be replaced upon construction completion.
The input rate and temperature rise must be set per the furnace rating plate.
One hundred percent (100%) outdoor air must be provided for combustion air requirements during construction.
Temporary ducting may supply outdoor air to the furnace. Do not connect duct directly to the furnace. Size the temporary duct following these instructions in section for Combustion, Dilution and Ventilation Air in a confined space with air from outside.
The furnace heat exchanger, components, duct system, air filters and evaporator coils must be thoroughly cleaned following final construction clean-up.
All furnace operating conditions (including ignition, input rate, temperature rise and venting) must be verified according to these installation instructions.

The Lennox EL195 manual also says,

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When the furnace is installed so that supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air must be handled by ducts which are sealed to the furnace casing and which terminate outside the space containing the furnace.

Download the Gastite Guide Here

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DIRECT CONTACT between continuous metallic systems and Gastite® yellow CSST is prohibited.  Maintain as much isolation/separation as reasonably possible when planning and installing gas piping from other continuous metalllic systems. Refer to sec. 4.3 Routing, in the Gastite D&I Guide for installation techniques.  Consult local building codes as to required separations for CSST from such continuous metallic systems including metallic chimney liners, metallic appliance vents, metallic ducting and piping, and insulated or jacketed electrical wiring and cables.  See for instance the Indiana Residential Code, section 675 IAC 14-4.3-155.5 Section G2411.1; gas pipe bonding.

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Direct contact between Gastite® yellow CSST and continuous metallic systems is prohibited. When supporting Gastite® CSST tubing runs, the use of other conductive metallic systems such as metallic appliance vents, metallic ducting and piping, and insulated or jacketed electrical wiring and cables should be avoided.

If you use the black FlashShield CSST you would not have to worry about this.  Just remember to identify it with yellow tape.

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There is no requirement to maintain separation from other electrically conductive systems when routing FlashShield

Offline Attavior

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Re: No return air plenum. Gastite direct contact with ducting
« Reply #2 on: November 20, 2016, 05:54:43 AM »
Union gas does construction heat,  but it needs to be applied for. I doubt the inspector would leave it unlocked knowing it is a conversion (assuming it's a conversion). .

Union gas soon to be enbridge anyway.  It's parent company was bought out by Enbridge in September. 

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Re: No return air plenum. Gastite direct contact with ducting
« Reply #3 on: November 20, 2016, 08:50:26 AM »
I didn't know that.  Enbridge has taken over!

I had assumed this was new construction, but if it's an occupied home then there probably is no option to order a construction heat unlock.