Protocol for Tankless Water Heaters

[randynavarro]

Anyone have any good inspection methods for looking at these other than staring at 'em and making sure hot water is coming out the tap and making sure they're vented correctly?

[charlieb]

Funny you ask. I just got on to get some info Katen? posted recently.

To answer your question-get the install instructions for the appliance. They will tell you all you MUST know. They vary.

[hvacman]

As "Charlie" stated....there is NO subsitute for the factory install manual. But a few key points, is the unit taking combustion air from outside or inside through a coaxial (dual) vent pipe. If it is taking combustion air from inside the space/home, you have to meet the square foot space to btu/hr requirement of all appliances in that space as per NFPA 54 fuel gas code. NOTE: then it can't be installed in a closed closest / room ! Watch out for flexible gas whips and gastite feeding the unit, Noritz cautions the installer NOT to use them, due to the restriction they cause for proper gas flow, or in the case with Gastite....size the feed line way up to compensate for the flow restriction. Black iron pipe is best. Water feed lines in and out of unit should be 3/4 inch for best flows.......

[hausdok]

Hi All,

I suggest we here at TIJ try to collaborate to create our own TIJ generic tankless water heater inspection checklist.

TIJ has a working relationship with Rheem/Ruud Corporation. I've posted a proposed checklist below that is based on an installation checklist taken from one of their tankless manuals. Let's modify/enhance it to create one that will work for our profession.

To flesh this thing out we need to fill in all of the blanks from what resources we have and then discuss what's needed for those areas where we don't have specs/codes and try and create a consensus-based working product.

Here's how it works. I'll post the basic list below. Then, those who want to participate, can click on the "reply with quote" icon and add their information after the quotes where necessary. Do not make this stuff up. Find it in codes, manuals, etc. and make it brief. Add it to the basic list and then explain your additions below the quoted areas, so that others will know where you got it from and why it's necessary.

ONE TEAM - ONE FIGHT!!!

Mike

Here it is:

---------------------

TIJ Tankless Water Heater Inspection Checklist *id="size4">

Outdoor and Indoor Water Heater Location

[ ] Proper clearance from combustible surfaces observed. (_______________________________)

[ ] Sufficient fresh air supply for proper operation of water heater. (_______________________)

[ ] Air supply free of corrosive elements and flammable vapors. (________________________)

[ ] Provisions made to protect area from water damage. (_________________________)

[ ] Sufficient room to service heater. (__________________________)

[ ] Combustible materials, such as clothing, cleaning materials, rags, etc. clear of the heater and vent piping. (__________________________)

[ ] Water heater is properly attached to the wall. (____________________________)

Water Supply

[ ] Water supply has sufficient pressure. (__________________________)

[ ] Air purged from water heater and piping. (________________________)

[ ] Water connections tight and free of leaks (_________________________)

[ ] Water filter is clean and in place. (___________________________)

[ ] Materials used are as instructed in this manual. (______________________)

[ ] Water pipes are insulated and protected from freezing. (_______________________)

Gas Supply

[ ] Gas type matches rating plate. (________________________)

[ ] Gas supply pressure is sufficient for the water heater. (_______________________)

[ ] Gas line equipped with shut-off valve, union and sediment trap. (_________________________)

[ ] Approved pipe joint compound used. (____________________________)

[ ] Soap and water solution used to check all connections and fittings for possible gas leak. (________________________)

[ ] Gas Company inspected installation (if required). (_______________________)

Relief Valve

[ ] Pressure Relief Valve properly installed and discharge line run to open drain (___________________)

[ ] Discharge line protected from freezing. (________________________)

Venting (IndoorWater Heaters Only)

[ ] Materials used are as instructed in the manual. (_______________________)

[ ] Vent connector(s) pitched downward to termination (¼" per foot of length minimum) See page 13. (____________________________)

[ ] Vent connector(s) securely fastened together with high temperature silicone (500°F) (260°C) and airtight. (_____________________________)

[ ] All vent runs are properly supported. (_____________________________)

[ ] Vent terminal is properly installed. (___________________________)

[ ] Sufficient combustion air is available. (__________________________)

[ ] Maximum and minimum vent lengths are observed. (__________________________)

Electrical Wiring

[ ] Voltage matches rating plate. (____________________________)

[ ] Water heater is properly grounded. (________________________)

[ ] Supply cord and/or wiring meets all local codes. (__________________________)

*Adapted from the Rheem tank less water heater installation checklist.

[fqp25]

Originally posted by hausdok

[ ] Gas supply pressure is sufficient for the water heater. (_______________________)

[ ] Gas line equipped with shut-off valve, union and sediment trap. (_________________________)

Mike,

How about the appropriate size gas line? These tankless heaters' popularity is on the rise. We might start running into Do-it-yourself amature piping.

Some models may require 3/4" piping, and it can be real easy to connect a 3/4" x 1/2" reducer in the fitting, then connect 1/2" line (rigid or flex).

Most manufactures (Bosch, Takaji, Noritz, AO Smith) say not to use a smaller diameter size than the inlet of the heater.

As long as your checking the shut-off, union, and sediment trap(Rheem's fancy terminology), might as well check the inlet. Just a thought...

[hausdok]

It's a good thought! Use your "reply with quote feature and add that to the list, so we can continue to built it and will be able to see it in the most recent post with changes, instead of scrolling up and down to it.

OT - OF!!!

M.

[fqp25]

Originally posted by hausdok

Hi All,

I suggest we here at TIJ try to collaborate to create our own TIJ generic tankless water heater inspection checklist.

TIJ has a working relationship with Rheem/Ruud Corporation. I've posted a proposed checklist below that is based on an installation checklist taken from one of their tankless manuals. Let's modify/enhance it to create one that will work for our profession.

To flesh this thing out we need to fill in all of the blanks from what resources we have and then discuss what's needed for those areas where we don't have specs/codes and try and create a consensus-based working product.

Here's how it works. I'll post the basic list below. Then, those who want to participate, can click on the "reply with quote" icon and add their information after the quotes where necessary. Do not make this stuff up. Find it in codes, manuals, etc. and make it brief. Add it to the basic list and then explain your additions below the quoted areas, so that others will know where you got it from and why it's necessary.

ONE TEAM - ONE FIGHT!!!

Mike

Here it is:

---------------------

TIJ Tankless Water Heater Inspection Checklist *id="size4">

Outdoor and Indoor Water Heater Location

[ ] Proper clearance from combustible surfaces observed. (_______________________________)

[ ] Sufficient fresh air supply for proper operation of water heater. (_______________________)

[ ] Air supply free of corrosive elements and flammable vapors. (________________________)

[ ] Provisions made to protect area from water damage. (_________________________)

[ ] Sufficient room to service heater. (__________________________)

[ ] Combustible materials, such as clothing, cleaning materials, rags, etc. clear of the heater and vent piping. (__________________________)

[ ] Water heater is properly attached to the wall. (____________________________)

Water Supply

[ ] Water supply has sufficient pressure. (__________________________)

[ ] Air purged from water heater and piping. (________________________)

[ ] Water connections tight and free of leaks (_________________________)

[ ] Water filter is clean and in place. (___________________________)

[ ] Materials used are as instructed in this manual. (______________________)

[ ] Water pipes are insulated and protected from freezing. (_______________________)

Gas Supply

[ ] Gas type matches rating plate. (________________________)

[ ] Gas supply pressure is sufficient for the water heater. (_______________________)

[ ] Gas line equipped with shut-off valve, union and sediment trap. (_________________________)

[ ] Gas supply line correct size. (_________________________)

[ ] Approved pipe joint compound used. (____________________________)

[ ] Soap and water solution used to check all connections and fittings for possible gas leak. (________________________)

[ ] Gas Company inspected installation (if required). (_______________________)

Relief Valve

[ ] Pressure Relief Valve properly installed and discharge line run to open drain (___________________)

[ ] Discharge line protected from freezing. (________________________)

Venting (IndoorWater Heaters Only)

[ ] Materials used are as instructed in the manual. (_______________________)

[ ] Vent connector(s) pitched downward to termination (¼" per foot of length minimum) See page 13. (____________________________)

[ ] Vent connector(s) securely fastened together with high temperature silicone (500°F) (260°C) and airtight. (_____________________________)

[ ] All vent runs are properly supported. (_____________________________)

[ ] Vent terminal is properly installed. (___________________________)

[ ] Sufficient combustion air is available. (__________________________)

[ ] Maximum and minimum vent lengths are observed. (__________________________)

Electrical Wiring

[ ] Voltage matches rating plate. (____________________________)

[ ] Water heater is properly grounded. (________________________)

[ ] Supply cord and/or wiring meets all local codes. (__________________________)

*Adapted from the Rheem tank less water heater installation checklist.

[hausdok]

So, should that area in parenthesis read 3/4" for XXXXXBtu, 1" for XXXXXBtu, etc?

The parenthesis are there so that others can help us get that information and fill it in where it applies, so that the list that the checklist we end up with is as complete as possible.

I don't have an unlimited amount of time on my hands to look all of this stuff up. Besides TIJ, I've got my inspection business to run, so, if we're going to do this thing, it's going to require more cooperation from the brethren.

OT - OF!!!

M.

[fqp25]

TIJ Tankless Water Heater Inspection Checklist *id="size4">

Outdoor and Indoor Water Heater Location

[ ] Proper clearance from combustible surfaces observed. (_______________________________)

[ ] Sufficient fresh air supply for proper operation of water heater. (_______________________)

[ ] Air supply free of corrosive elements and flammable vapors. (________________________)

[ ] Provisions made to protect area from water damage. (_________________________)

[ ] Sufficient room to service heater. (__________________________)

[ ] Combustible materials, such as clothing, cleaning materials, rags, etc. clear of the heater and vent piping. (__________________________)

[ ] Water heater is properly attached to the wall. (____________________________)

Water Supply

[ ] Water supply has sufficient pressure. (__________________________)

[ ] Air purged from water heater and piping. (________________________)

[ ] Water connections tight and free of leaks (_________________________)

[ ] Water filter is clean and in place. (___________________________)

[ ] Materials used are as instructed in this manual. (______________________)

[ ] Water pipes are insulated and protected from freezing. (_______________________)

Gas Supply

[ ] Gas type matches rating plate. (________________________)

[ ] Gas supply pressure is sufficient for the water heater. (_______________________)

[ ] Gas line equipped with shut-off valve, union and sediment trap. (_________________________)

[ ] Gas supply line correct size. 1/2" up to 150,000 Btu 3/4" Up to 200,000 BTU 1"_____

[ ] Approved pipe joint compound used. (____________________________)

[ ] Soap and water solution used to check all connections and fittings for possible gas leak. (________________________)

[ ] Gas Company inspected installation (if required). (_______________________)

Relief Valve

[ ] Pressure Relief Valve properly installed and discharge line run to open drain (___________________)

[ ] Discharge line protected from freezing. (________________________)

Venting (IndoorWater Heaters Only)

[ ] Materials used are as instructed in the manual. (_______________________)

[ ] Vent connector(s) pitched downward to termination (¼" per foot of length minimum) See page 13. (____________________________)

[ ] Vent connector(s) securely fastened together with high temperature silicone (500°F) (260°C) and airtight. (_____________________________)

[ ] All vent runs are properly supported. (_____________________________)

[ ] Vent terminal is properly installed. (___________________________)

[ ] Sufficient combustion air is available. (__________________________)

[ ] Maximum and minimum vent lengths are observed. (__________________________)

Electrical Wiring

[ ] Voltage matches rating plate. (____________________________)

[ ] Water heater is properly grounded. (________________________)

[ ] Supply cord and/or wiring meets all local codes. (__________________________)

*Adapted from the Rheem tank less water heater installation checklist.

These figures are from Bosch Aqua Star 125FX, which rated at 125,000Btu, and has a 1/2" gas inlet. The AO Smith XT-190 is rated at 190,000 Btu and has a 3/4" inlet.

I am uncertain where exactly you would step-up the inlet, wouldn't that differ between manufactures? I just entered 150,000 Btu for 1/2" and 200,000 for 3/4", if anyone can be more accurate please correct this.

[hausdok]

Now we're talking.

Maybe that information is available someplace on the GAMA site.

OT - OF!!!

M.