How To Look At A House

McGarry and Madsen's home inspection blog for buyers of  

site-built, mobile/manufactured and modular homes


Monday, May 28, 2018

Here’s links to a collection of our blog posts about WATER HEATERS:

What is a "tabletop" water heater?

Are water heaters required to be raised off the floor? 

Can a Temperature and Pressure Relief (TPR or T&P) valve be mounted to discharge horizontally?

Where are gas water heaters not allowed to be installed?  

Is a double heating element water heater better than a single element water heater?

Is the minimum size water heater inlet pipe 1/2" or 3/4" according to the building code? 

Can you use a light switch for a water heater disconnect? 

How can I tell if a water heater is HUD-approved for mobile/manufactured homes?

Can you wire a 240-volt water heater with 120 volts? 

Is it alright to have a shut-off valve on both the hot and cold water pipes at a water heater?  

What is the minimum clearance to doors and windows for an outdoor tankless gas water heater? 

What is required clearance for access and working space in front of an electric water heater? 

Why is the water heater older than the house? 

Does a water heater need a shut-off valve? 

Why should a tankless water heater have an isolator/service valve kit installed?

When was a gas water heater first required to be elevated 18 inches above a garage floor? 

Can the temperature and pressure relief (TPR) valve discharge pipe for a mobile/manufactured home water heater terminate under the home? 

What is the purpose of a thermostatic mixing valve above a water heater? 

Does a tankless gas water heater still work with no electricity during a power outage? 

Why do water heaters have a sacrificial anode? 

What is the difference between a manufactured/mobile home water heater and a regular water heater? 

Does a tankless water heater require a pressure relief valve?

When is a water heater drain pan required?

Why is there water in my water heater drain pan?

What does it mean when a water heater Temperature/Pressure Relief (TPR) discharge pipe is "trapped"? 

Can I leave a gas water heater in place when remodeling a garage into a family room or bedroom? 

Where do I find the water heater in a mobile home?

Does a tankless water heater in an attic require a drain pan? 

Does an electric water heater require a disconnect?

Is a catch pan and drain piping required for a replacement water heater?

What is the difference between a single element and dual element electric water heater? 

What is an FVIR water heater?

What is a heat pump water heater?

What is a dielectric union?

What's that powdery crust on the pipe connections at the water heater? 

What are the most common installation mistakes with water heater replacement?

Why is my water heater making strange (rumbling, gurgling, knocking or banging) noises? 

What can I do to make my water heater last longer?

How does a hydronic heating system work?

What is the difference between a regular water heater and a direct vent water heater? 

What is the difference berween a regular water heater and a power vent water heater?

What is backdrafting at a gas water heater? 

How do I determine if a water heater is gas or electric?

What does it mean when a gas appliance (water heater, furnace, or range) has been "red tagged"? 

Why does the water have a rotten-egg smell in some empty houses? 

• What's the valve with the flip-up handle on the water heater for?

• Why is an older water heater an insurance problem?

• What is the average lifespan of a water heater?

• What is the First Hour Rating (FHR) of a water heater? 

Can you connect CPVC pipe directly to a gas water heater?  

• What are the special code requirements for installation of a gas water heater in a garage?

• Can a water heater Temperature/Pressure Relief (TPR or T&P) valve to mounted to discharge upward? 

• What is a "heat loop" at a water heater?

• Can I replace a single element water heater with a double element one? 

What are the code requirements for the discharge piping from a Temperature-Pressure Relief (TPR) valve at a water heater? 

• Do I need a pan under a water heater in the garage? 

Can a grille covering a hole in the drywall ceiling be used for the required make up (combustion supply) air for a gas water heater or furnace in a garage?

 What is the red switch for in my mobile home? 

Can you use PVC pipe for the water heater temperature pressure relief (TPR) discharge pipe?

• How much clearance is required around a gas water heater? 

 Is it safe to sleep in a room with a gas water heater?

• Can you install a gas water heater in a bedroom? 

Can you install a gas water heater in a bathroom?

• Can you install a gas water heater in a closet? 

How can I tell if a water heater is 240-volt or 120-volt?

What is the small pipe on the side of the house that is dripping water? 

What is the best location for a water heater in a house?

What does a home inspector check at a water heater? 

Can a water heater and air conditioner use the same drain?

Can a Type B vent connector be run horizontally? 

Can you use PEX as discharge pipe at water heater temperature and pressure  relief (TPR) valve?

Why is a leaning water heater a safety problem?

• Can PEX pipe be connected to a water heater? 

When were gas water heaters first required to be FVIR (Flammable Vapor Ignition Resistant)?

What is the little tank on top of the water heater for? 

Can a water heater thermal expansion tank be installed sideways/horizontally?

• Do I need a permit to replace my water heater? 

Is a water softener bad for my water heater? 

Are water heater expansion tanks required by code? 

Is a thermal expansion tank required for tankless water heaters? 

• Can a water heater be cord and plug connected?

• Can a tank water heater be installed outdoors? 

• How do I move a water heater?

Is water heater corrosion a sign it’s time for replacement? 

• What does ECO INSTALLED mean on a water heater data sticker? 

Can I install water heater in the crawl space by code?

• Is a drain pan required for a small (2.5 to 6 gallon) water heater? 

What are the signs it's time to replace my water heater?

When were water heater thermal expansion tanks first required by code? 

• Can you use an electrical cord and plug for an exterior tankless gas water heater?

• What causes the powdery crust on CPVC pipe connections at the water heater? 

• What is the difference between a Temperature and Pressure Relief (TPR) Valve and a Thermal Expansion Pressure Relief Valve? 

Can a Temperature and Pressure Relief Valve (TPR) and Thermal Expansion Pressure Relief Valve share the same discharge pipe?

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