We are here to tell you that it is okay for some water heaters to be without temperature-pressure relief valves. The valve’s sole purpose is to keep the pressure and temperature inside of a tank below certain levels. By most standards, the benchmarks are 150 psig and 210 F, respectively.
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Can you have a tankless water heater without a valve?
They wonder if the missing valve makes the tankless water heaters less efficient or prone to break downs. We are here to tell you that it is okay for some water heaters to be without temperature-pressure relief valves. The valve’s sole purpose is to keep the pressure and temperature inside of a tank below certain levels.
How to protect pipes from tankless water heater?
Here are some tankless water heater enclosures for pipes that will protect them and also just look nicer in general. You can cover the pipes with insulation foam to look prettier and also to prevent too much heat loss. Application: For covering the water and gas piping of the RL75i/e, RL94i/e,...
What is the plumbing code for a tankless water heater?
(CPC 505.1). Another thing, the plumbing code, is not mentioning is the tankless water heater clearance, and it also up to the every manufacturer to set the clearance from combustible and non-combustible materials. Minimum ¾ inch T&P drain to terminate “outside” of the building no closer than 6 inches or further than 24 inches from grade.
Does a Takagi tankless water heater have a pressure relief valve?
The Takagi gas-fired tankless water heater manual specifies a pressure relief valve on the hot water outlet. Here’s an excerpt from that manual: So consult the manufacturer’s installation manual. Gas-fired tankless water heaters will usually require a pressure relief valve, while electric on-demand water heaters may not.
Does a tankless water heater need a pop off valve?
Gas-fired tankless water heaters will usually require a pressure relief valve, while electric on-demand water heaters may not. The manufacturers typically only require a pressure relief valve, not the combination temperature and pressure relief valve that is necessary for tank-type water heaters.
Do tankless water heaters have a mixing valve?
Tankless water heaters have many selling points for use in smaller domestic hot water delivery systems. But the idea that these systems don't need a mixing valve, shouldn't be one of them. There are 2 main areas of safety that you need to consider in that design: Minimize the potential for a scalding hazard.
Do I need a backflow preventer on my tankless water heater?
Backflow preventers are now required by many plumbing codes to be installed in the cold water supply line from the street. Before the days of backflow preventers, the expanding water in the hot water tank could push backwards into the main water supply.
Can you flush a tankless water heater without isolation valves?
Although isolation valves are not necessary for flushing out some tankless water heater heat exchangers, they make the job much simpler.
Are mixing valves mandatory?
As a result of the speed at which people can get burned, legislation was introduced to require thermostatic mixing valves on any new or replacement water heater installation.
Where are mixing valves required?
For combined heating hot water and domestic hot water systems, when the heating hot water system exceeds 140°F the IPC code requires a temperature actuated mixing valve conforming to ASSE 1017 to limit the domestic hot water temperature to a maximum of 140°F.
How do you install a pressure relief valve on a tankless water heater?
Screw the valve into the port on the lower edge of the tankless heater by hand. Fit an adjustable wrench onto the flat portion of the valve and continue to tighten the valve clockwise. Stop when the valve is reasonably tight and the pressure-release lever is facing toward the outer edge of the tank.
How do you install an isolation valve on a tankless water heater?
3:1522:38Tankless Water Heater Valve kit Tutorial - YouTubeYouTubeStart of suggested clipEnd of suggested clipNow you take that valve gently thread it directly on to your hot water outlet of your tankless unit.MoreNow you take that valve gently thread it directly on to your hot water outlet of your tankless unit. And again you can throw edit the majority of the way by.
Do hot water heaters have a backflow preventer?
With a properly installed and tested backflow preventer, water will be unable to flow back into the public water pipes. The backflow preventer creates an isolated or closed plumbing system. For some homeowners, this could produce leaky faucets or set off the relief valve on hot water heaters.
What happens if you don't flush your tankless water heater?
What happens if I don't flush out my tankless water heater? Mineral deposits may build up. This could cause a clog within the unit and may prevent normal heating activity. Your hot water could also fluctuate and overheat the system, impacting its efficiency.
How much does it cost to flush a tankless water heater?
It costs around $150 to flush a tankless water heater. You especially need it at least annually if you have well water with a lot of iron. That causes more sediment buildup. The process takes about a half-hour.
What maintenance is needed on a tankless water heater?
The good news is that tankless water heaters don't require much maintenance, either. A tankless system should be serviced as a part of the regular preventive maintenance that heating and cooling systems receive. Electric or gas components should be inspected.
Does replacing the Tankless water require a plumbing permit?
Local jurisdictions (cities , counties) require a plumbing permit to install a new tankless electric water heater and gas water heater as well.
Who can apply for a plumbing permit?
Per CSLB a C-36 – Plumbing Contractor. However, if the homeowner is doing the work himself/herself, the local jurisdictions will allow him/her to obtain the plumbing permit.
Tankless water heater Location
The location of the tankless water heater per the plumbing code is not listed. The manufacturer of the water heater specify if the water heater is suitable for installation indoor or/and outdoor, so I recommend reading the manufacturer specs before purchasing if you have specific location in mind.
Tankless water heater clearance
Another thing, the plumbing code, is not mentioning is the tankless water heater clearance, and it also up to the every manufacturer to set the clearance from combustible and non-combustible materials.
Temperature and Pressure (T & P) Relief Valve & Discharge Line Water
Minimum ¾ inch T&P drain to terminate “outside” of the building no closer than 6 inches or further than 24 inches from grade.
Gas line sediment trap (drip leg)
Sediment trap (T, 3” minimum nipple and cap) installed on water heater’s gas supply. (CPC- UPC 1212.7).
Water lines shutoff
A full bore shut off valve is required on cold water side only, but preferably on cold and hot water lines.
What happens when a pressure relief valve goes bad?
When temperature-pressure relief valves go bad, one of two things generally happens. First, conditions inside of the tank may reach dangerous levels. Those elevated levels could lead to small or large breaks in the tank, including major explosions. Second, the valves could cause water leaks, which in turn could create structural problems inside ...
Do you have a new tankless water heater?
Do you have a new tankless water heater? Chances are good that you were taught by your parents or grandparents to periodically open the pressure-relief valve on your home’s water heater. Perhaps they told you why the valve has to be opened from time to time or maybe they did not share that part with you.
Do tankless water heaters have pressure relief valves?
As such, many people are surprised to learn that some ,models of tankless water heater do not have pressure relief valves. They wonder if the missing valve makes the tankless water heaters less efficient or prone to break downs.
Can a water heater be without a pressure relief valve?
We are here to tell you that it is okay for some water heaters to be without temperature-pressure relief valves. The valve’s sole purpose is to keep the pressure and temperature inside of a tank below certain levels. By most standards, the benchmarks are 150 psig and 210 F, respectively. So those periodic checks you were told to make are merely to ensure that the valve is still working effectively.
How much clearance does a tankless water heater need?
If the window does not open, the tankless water heater clearance from a window requires a 12-inch setback. Tankless water heaters should not be installed near dryer vents or intake air vents.
Do you have to be close to the water source for a vent?
That is the biggest factor when selecting the location for the installation. Yes, you want to be close to the source of your gas or water. But, if you need to vent to the outside then there are certain codes and clearances that may not allow you to be too close to your source.
Can you use a metal exhaust vent?
An exhaust vent can be metal or PVC, but what kind of unit will determine which you can use. For instance, a metal or stainless steel vent exhaust will get very hot and will cost more to seal to the wall since you can’t use a silicone to seal the gap. A concentric or condensing unit will solve this problem.
Can you use a tankless water heater on the roof?
Tankless water heaters use fans to blow exhaust from the unit horizontally, allowing vents to terminate on the side of a house. You can’t use an existing tank vent if it goes from the basement to the roof. Keep in mind that you will likely need to drill through a wall to do this.
Do I need a permit to install a tankless water heater?
While you may not need a permit specifically for a tankless water heater installation in your area, chances are good that you need a permit to replace a water heater in general. This is the first thing you need to sort out before you do anything.
Do you have to have a tankless water heater?
That said, you are still required to have a certain tankless water heater clearance to windows and other factors.
Can you vent out of a chimney?
Not only that, but since the gases from the exhaust are highly corrosive, so you can’t vent out of a masonry chimney flue. Also, a galvanized vent from a storage tank heater will quickly rust and dissolve away. Not only is this going to cause you a financial headache to replace, it is extremely dangerous.
How long does it take for a tankless water heater to work?
This typically takes about 2-3 minutes depending on how far away the fixture is from the tankless water heater.
What is thermal expansion tank?
A thermal expansion tank is designed to control and reduce water pressure within the plumbing system. When water pressure gets too high, it can damage plumbing valves, weaken supply pipe joints and shorten the life of your water heater itself. These issues not only cause problems in your home but are expensive to fix.
Why does my water heater explode?
As the water is heated in a storage tank, water converts to vapor which increases the pressure in the plumbing pipes. Without a place for pressure to release during thermal expansion, your tank-style water heater could explode. Quick Article Navigation Show. Expansion Tanks and Tankless Water Heaters.
What does it mean when a house has a closed water supply?
If the house has a closed plumbing supply, meaning there is a check valve or backflow preventer that prohibits the release of water pressure building back into the water main. Water pressure in the plumbing system is created by the heating of water.
Do tankless water heaters need expansion tanks?
Most tankless water heaters (electric or gas) do not need a thermal expansion tank. The reason being is that a tankless water heater only produces hot water as requested. When the hot water supply is opened, the tankless unit starts to produce hot water.
Do tankless water heaters store hot water?
Tankless water heaters do not store hot water as it is created on-demand. Meaning when you open the hot water tap, the water heater produces hot water to travel to the hot water tap. When the tap is closed, the water heater stops producing hot water.
Does a tankless water heater have thermal expansion?
Water is heated only when a hot water tap is opened. Since the tankless water heater does not produce and store hot water in a storage tank, no thermal expansion occurs to place thermal pressure on the plumbing system.
Do tankless water heaters need a drain pan?
Every major manufacturer of tankless water heaters specifies that a catch pan and drain piping be installed under the unit if leakage would cause damage to the immediate area, and that is certainly the case when one is installed in an attic. Also, the International Residential Code (IRC) requires that a drain pan be installed “where leakage ...
Is there a drain pan under a tankless water heater?
Yes, it is a drain pan and it is under the water heater, but the TPR valve drain piping was routed through a roughly cut-out hole in the side of the pan, ...
Do you need a drain pan for a tankless tank?
Also, the International Residential Code (IRC) requires that a drain pan be installed “where leakage of the tanks or connections will cause damage.”. A tankless obviously does not have a storage tank, but it does have pipe connections that can leak as the unit reaches the end of it serviceable lifespan. So a drain pan is definitely required ...
