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Hot Water Heater Replacement in a mobile home.

Can I install a commercial grade 50 gallon hot water heater in my 1985 mobile home? I am concerned about the weght as my old hot water heater was 19 gal. Space is not a issue. I know I will have to run a line and it will need its own breaker. My concern is when I fill it up with water it falling thru the floor. Also I was told by someone (not an expert or contractor) that I have to purchase a hot water heater especially designed for a mobile home. Is this true? What is the difference between hot water heaters?

Re: Hot Water Heater Replacement in a mobile home.

We just covered this topic a couple of weeks ago, if you want to search it.

Use a "mobile Home water heater" for a mobile home. There are a few reasons why:

1. Compact size.
2. Mobile homes are plumbed for specific water heaters.
3. Air supply and source.
4. Insurance: your insurer may deny a claim if they found out you installed a residential heater in your mobile Home.
5. Modifications: for a residential unit you'll have to run new water lines, vent, gas line (requires a permit).
6. Weight issue, as you mentioned in your post. A gallon of water is about 8 lbs. Do the math and see how much weight you'll be adding on the floor.

There are more, do you need more?

Of course, if you insist on doing the conversion, it could be done, with the cost.

A. Spruce
Re: Hot Water Heater Replacement in a mobile home.

Is there a difference between a "trailer" water heater and a standard residential water heater? Yes, it is a shiny sticker on the side that says "trailer rated", and the cost of this shiny sticker is a mere several hundred dollars. Is there a physical difference, no, not likely, however, if you choose to use a non-certified appliance in a trailer, you will nullify your insurance coverage, which you likely won't know about until it's too late. Your choice, just know that there are consequences.

As for a larger water heater, odds are that it won't be an issue as long as the existing floor and framing are sound. If there is any sponginess to the floor, I'd recommend opening it up and repairing it before installing the new water heater. In addition, if space is not an issue, then possibly moving the water heater where it is being fully supported by structure, and not just the cheap and cheesy particle board that trailer manufacturers love to use in everything.

Re: Hot Water Heater Replacement in a mobile home.

There's no inherent difference between most home and trailer water heaters save for the sticker. The differences happen when you find it in an odd-sized location with odd-style plumbing connections, so don't expect a 'drop-in' fit. Also keep in mind the required clearances of the new unit which will be listed in it's owners manual. As to weight, I prefer to cover the whole floor area housing the WH with Advantek or equivalent to spread the load as much as possible- there's usually room to do this. That should be enough to support any reasonably sized residential WH, but if you want just make sure it has at least one joist under the WH itself or that the Advantek will transfer the load directly to 2 joists. This is almost always the case.

Trailers are built to different codes compared to houses, hence the 'trailer rating' stickers. The testing standards for homes are usually higher and the only place I worry about anything is when dealing with HVAC systems; these are often placed in tight quarters and rated for the small clearances involved whereas home-code units require more clearance for fire safety purposes. With your WH, just maintain the clearances the manufacturer wants, adapt the piping as necessary (I like shut-offs on both sides) and make sure the T&P valve drain goes directly to the outside of the envelope and will not flood the insulation underneath if it opens.

One other thing to be aware of: I'm not sure if you have aluminum wiring- the vintage you speak of was about the time trailers switched to copper. Aluminum requires special parts, handling, and techniques and must not be treated as if it were copper. And sometimes the breakers are odd ones too, those may need to be sourced through a MH supply if standard ones will not interchange.

As you're finding out, trailers are a whole lot different than stick-built homes and the differences are usually not good for your pocket when repairs are needed. Plus the parts quality is usually awful, even at three prices too costly. I recommend that as you need to work on it, you replace all the plumbing with standard stuff since it's cheaper and better, check the HVAC system for leaks and insulation as most are awful at best, and that you watch very closely for any and all water leaks which will kill a trailer in record time compared to a stick-built home. A well-kept trailer can make for a good home but they don't tolerate any maintenance abuse at all.


Re: Hot Water Heater Replacement in a mobile home.

Gas water Heaters for a Manufactured or Mobile Home are code specific. IN Arizona a Gas water heater must say ( for use in a mobile home only) on the water heater itself. The difference is in the changeable orifices, from natural to propane or visa versa. Even though Manufactured or mobile homes are not moved around from place to place, It is the code that effects the install not the location. Yes Gas specific water heaters are less expensive and make the price more appealing to the homeowner. The problem comes when you try to sell your Home or you have a gas leak somewhere. The inspection when selling will show up a non-compliant water heater, and the homeowner will then have to replace with a code compliant mobile home water heater, before sale will go thru. If a leak occurs, the gas company upon see the non compliant water heater, will shut off the Gas to the water heater and it will not be turned back on until water heater is replaced with code compliant. Electric water heaters for mobile homes are not so strictly monitored, so you may put a regular water heater in your mobile home. Though some inspectors want to see a HUD approved unit. Be advised, the Mobile Home electric water heater, (much more expensive) has only 1 (one) Element. Which will have a lower recovery rate. General 40 gallon Electric water Heaters are LESS expensive than 30 Gallons. For Arizona Manufactured or Mobile homeowners see www.manufacturedhomeplumbing.com

Re: Hot Water Heater Replacement in a mobile home.

As you have indicated the need for a new breaker, I am assuming you will install an electric WH. Check with your local building department, generally electric wh's pose no problem.


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