[Protech]

607.2 Hot water supply temperature maintenance. Where the developed length of hot water piping from the source of hot water supply to the farthest fixture exceeds 100 feet (30 480 mm), the hot water supply system shall be provided with a method of maintaining the temperature in accordance with Chapter 13 of the Florida Building Code, Building. 607.2.1 Minimum pipe insulation. Circulating hot water piping and domestic and service hot water systems with fluid design operating temperatures greater than 105°F (41°C) shall be insulated in accordance with the requirements of Table 607.2.1.

TABLE 607.2.1 MINIMUM PIPE INSULATION (in)a,b Domestic and Service Hot Water Circulating Systemsa




So, am I reading this wrong, or does this mean that if the developed length on a hot water line is more than 100' a recirc pump must be installed?

 

[Plumber Jim]

Looks like it to me.

 

[Bayside500]

my guess is it needs to be insulated, there is a Florida energy code i think, my boss told me about it ?

i bet house plumber will know

 

[Protech]

The only thing I can find in the sited chapter 13 of the building code that relates to plumbing is insulated recirculation systems.

Since that is the only thing related to plumbing in that chapter, I have to conclude that a recirc system is mandatory on all 100' + systems.

 

[Protech]

Chapter 13 of the Florida Building Code, Building:

<Snip>

SECTION 13-611 PIPING

13-611.AB Mandatory requirements for Methods A or B.

13-611.AB.1 Piping insulation. All piping installed to service buildings and within buildings, including the vapor line of HVAC refrigerant piping, shall be thermally insulated in accordance with Table 13-611.AB.1, except as stated herein (for service water heating systems, see Section 13-612.AB.5).

Exceptions: Piping insulation is not required in the following cases:

1. Piping installed within HVAC equipment.

2. Piping containing fluid at temperatures between 55°F and 120°F (13°C to 49°C).

3. Piping within the conditioned space.

4. Piping within basements or unvented crawl spaces (plenums) having insulated walls.

TABLE 13-611.AB.1 MINIMUM PIPE INSULATION

Piping System Types Fluid Temperature
Range°F Runouts2
(inches) Insulation for Pipe <
1" Thickness Sizes1
1.25 - 2" HEATING SYSTEMS
Steam and hot water
Low pressure/temp.
Low temperature
Steam condensate (for feed water)

201 - 250
120 - 200
Any

1.0
0.5
1.0

1.5
1.0
1.0

1.5
1.0
1.5 COOLING SYSTEMS
Chilled water, refrigerant or brine 40 - 55
Below 40 0.5
1.0 0.5
1.0 0.75
1.50

For SI: 1 inch = 25.4 mm, °C = [(°F)-32]/1.8
1. For piping larger than 1 inch diameter and exposed to outdoor ambient temperatures, increase thickness by 0.5 inch.
2. Runouts to individual thermal units (not exceeding 12 feet in length).
3. The required minimum thicknesses do not consider water vapor transmission and condensation. Additional insulation, vapor retarders, or both, may be required to limit water vapor transmission and condensation.

<snip>

SECTION 13-612 WATER HEATING SYSTEMS

13-612.AB Mandatory requirements for Methods A or B.

13-612.AB.1 Sizing. Reserved.

13-612.AB.2 Controls.

13-612.AB.2.1 Storage water heater temperature controls.

13-612.AB.2.1.1 Automatic controls. Service water heating systems shall be equipped with automatic temperature controls capable of adjustment from the lowest to the highest acceptable temperature settings for the intended use. The minimum temperature setting range shall be from 100°F to 140°F (38°C to 60°C).

13-612.AB.2.1.2 Shut down. A separate switch or a clearly marked circuit breaker shall be provided to permit the power supplied to electric service systems to be turned off. a separate valve shall be provided to permit the energy supplied to the main burner(s) of combustion types of service water heating systems to be turned off.

13-612.AB.2.2 Heat traps. Storage water heaters not equipped with integral heat traps and having vertical pipe risers shall have heat traps installed on both the inlets and outlets. External heat traps shall consist of either a commercially available heat trap or a downward and upward bend of at least 3 1/2 inches (89 mm) in the hot water distribution line and cold water line located as close as possible to the storage tank.

 

[OldSchool]

13-612.AB.2.2 Heat traps. Storage water heaters not equipped with integral heat traps and having vertical pipe risers shall have heat traps installed on both the inlets and outlets. External heat traps shall consist of either a commercially available heat trap or a downward and upward bend of at least 3 1/2 inches (89 mm) in the hot water distribution line and cold water line located as close as possible to the storage tank.

You never see any body do this.. even though it is a good idea

 

[Protech]

All of my heaters come with traps from the factory.

You never see any body do this.. even though it is a good idea

 

[OldSchool]

All of my heaters come with traps from the factory.

What make of hwt would that be.... because I dont think we have that here yet..

Also I wonder if a temperature mixing valve would be considered as a trap

 

[Protech]

American for my electrics. Rheem for gas (which is rare around here)

 

[Optimus Primer]

They were inforcing the 100ft rule. If the furthest fixture was 100 feet or more from the heater then they did require a recirc, but not anymore. No insulation either unless its on a recirc. Which would make sense to reduce heat loss. Funny, A st, petersburg inspector was just talking about that with me today.

 

[Optimus Primer]

You never see any body do this.. even though it is a good idea

yeah, havent done it in a while. We used to with overhead water lines. Now our heaters have them already

 

[Tommy plumber]

607.2 Hot water supply temperature maintenance. Where the developed length of hot water piping from the source of hot water supply to the farthest fixture exceeds 100 feet (30 480 mm), the hot water supply system shall be provided with a method of maintaining the temperature in accordance with Chapter 13 of the Florida Building Code, Building. 607.2.1 Minimum pipe insulation. Circulating hot water piping and domestic and service hot water systems with fluid design operating temperatures greater than 105°F (41°C) shall be insulated in accordance with the requirements of Table 607.2.1.

TABLE 607.2.1 MINIMUM PIPE INSULATION (in)a,b Domestic and Service Hot Water Circulating Systemsa




So, am I reading this wrong, or does this mean that if the developed length on a hot water line is more than 100' a recirc pump must be installed?

You're reading it correctly.

 

[IBEPLUMBING]

I wish I could read ch. 13 1st before answering. actually the whole book

607.2 If TDL is over 100 feet Key word is method of maintaining temp according to ch. 13. What does it say in ch. 13? Whats the heat loss rating on the insullation being used. Whats the heat loss on the water supply material per foot of water travel? Assuming you also have the psi to to do math. Center your water heater when drawing so the fixture units to the water heater have short runs. Bottom line need more info.

607.2.1 circ and hwh lines having tep over 105 need to be insulated according to table 607.2.1 ...again the table will tell.

Not enough info. Plus thats a terrible way of creating an energy efficient system. Look up PG&E here in CA and see the free energy efficiency classes

 

[SlickRick]

I read it as you have to choose the method to maintain the temp., either by insulation, recirc. or any other method that I may not be aware of. Keyword being method, not specific.

 

[Proud Plumber]

Are all pex mfg's approved for recirc now? Used to be that they did not want recirc on pex.

 

[Protech]

Are all pex mfg's approved for recirc now? Used to be that they did not want recirc on pex.

they are only approved aquastat recirc or for timer systems. if it is going to be a continuous recirculation system then the pipe must have an nsf-cl rating. there are only a few systems out there that have that rating. Uponor is not 1 of them.

 

[plumb nutz]

they are only approved aquastat recirc or for timer systems. if it is going to be a continuous recirculation system then the pipe must have an nsf-cl rating. there are only a few systems out there that have that rating. Uponor is not 1 of them.

Bad question, but why?

 

[Protech]

Bad question, but why?

Type A pex (Engle method) don't have much antioxidants in the resin due to the Engle process. Because of the heat used in the Engle process only a certain amount of antioxidants can be added. Continuous recirculation systems expose the pex to high temperature and high chlorine for extended periods of time. Brands that have minimal chlorine resistance (like Uponor) won't hold up in such aggressive conditions. They will dry out and split.

An example of a brand that is rated for continuous recirc would be Zurn (a type B pex).

If you look at Uponor's warranty, they specifically prohibite using their product in high chlorine conditions for exactlt this reason. In central Florida, it is not uncommon to test municipal water and get get 3-4ppm chlorine. This is enough to void Uponor's warranty WITHOUT any kind of recirculation system. Food for thought. BTW, I am not trying to bash Uponor. Just stating some facts.

 

[gladerunner]

So what do you do with your tankless systems? Install 1 every 100' ? I would imagine the code is to save on water consumption, but it seems like it would increase energy consumption

 

[OldSchool]

So what do you do with your tankless systems? Install 1 every 100' ? I would imagine the code is to save on water consumption, but it seems like it would increase energy consumption

Install it in the middle then you have 50 ft on both sides :laughing: