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mblibby
Hot water heater in unheated crawl space

Will the water in an electric hot water heater freeze in an unheated crawl space if we turn the electricity off to the water heater? My guess is it will but was't sure if it was insulated on the inside and thus would not. The house is in NH and we will be there maybe 4 or 5 weekends during the winter.

If it will freeze what is the best solution.

Leave water heater on
Turn it off and drain it every time we leave
Heat the crawl space.

Thank you,

Brad

keith3267
Re: Hot water heater in unheated crawl space

Insulation will only slow down the heat loss. If the air temperature in the crawl space goes below freezing, the water inside the water heater, and in all the water pipes, will freeze. If the house is left heated while you are gone, the air in the crawl space may not go below freezing.

But if you are trying to save on heating costs while you are gone, then you want to turn down the house heat to about 40-45°F, and that may allow the air temp in the crawl space to go below freezing. You could go into the crawl space and turn the water heater down to its minimum temp before you leave each time, but that will a pain in the rear, unless you have an unusually high crawl space. Also the minimum temp on the water heater could be in necessarily high.

My suggestion is heat tape. Ideally you would remove the outer tank cover and insulation, wrap heat tape around the water heater, reinstall the insulation and the outer tank cover. You might be able to snake the heat tape under the insulation in places such as down the side between the access covers, around the bottom and around the top, this would work just about as well.

If you have to put the heat tape on the outside, then you need to cover the whole tank with another layer of insulation to force the heat from the heat tape to go inward to the tank and not just radiate into the crawl space. While you are at it, run a little heat tape along the pipes and insulate over them as well.

Now you should be able to turn off the water heater and turn down the house heat. The heat tape only heats to about 40°F or so, but it doesn't use much electricity either. Be sure to turn off the main water supply as well and open the highest faucet in teh house, just in case something goes wrong.

plumbingjim17
Re: Hot water heater in unheated crawl space

Leave the water heater on vacation it won't use much gas and it will prevent freezing now the pipes are another story. Other option winterize the property before leaving vacant which in my opinion is the best option no worry of floods or pipes bursting or any other instances that could result in a insurance claim that most likely would be denied because most insurance companies consider homes left more than a couple days to a week neglect.

mblibby
Re: Hot water heater in unheated crawl space

Thank you for the response. The water heater is in a large crawl space that runs the whole elngth of the house. It is essentially a basement that is about 3 feet high with no finished floor. Given that I think I am going to try the heat tape route.

Brad

queen60
Re: Hot water heater in unheated crawl space

Hope the electicity doesn't go out while you're away.

JLMCDANIEL
Re: Hot water heater in unheated crawl space

In NH I would drain an winterize, While you say you will be there on some weekends a power outage during the week could cost you a lot of damage.

Jack

martindevid5
Re: Hot water heater in unheated crawl space

Hi,

I would like to share some best suggestion for water heater.

1.Always use the bathroom or kitchen exhaust fans while showering or cooking and baking to avoid potential moisture problems.
2. Use a microwave or toaster oven for smaller items.
3. Install a low-flow showerhead. Showers use less hot water than baths; also consider takingshorter showers.
4. Close your fireplace damper and seal the opening shut when not in use.
5. during the day. Close all window coverings at night to keep the heat in.
6. Install foam gaskets behind electric-outlet and switch-plate covers.
7. Examine and adjust, if necessary, weather stripping, door sweeps, and thresholds.

Asher81
Re: Hot water heater in unheated crawl space

You could go into the crawl space and turn the water heater down to its minimum temp before you leave each time, but that will a pain in the rear, unless you have an unusually high crawl space. Also the minimum temp on the water heater could be in necessarily high.

Tony_01
Re: Hot water heater in unheated crawl space

Insulating crawl space can help you to control the moisture and the overall temperature throughout the home. It will not let the water freeze and will solve your problem.

johnjh2o
Re: Hot water heater in unheated crawl space

Insulation doesn't create heat. If there is no heat source and the temperature is below freezing water will freeze, no matter how much insulation you use.

John

HoustonRemodeler
Re: Hot water heater in unheated crawl space

Since this is an electric tank and you have a crawl space you can-

1- Flip the breaker to turn the heater off

2- Plumb the house so there is a master water shut off (You already have that) and 2 more drain lines with shut offs; one for the cold water pipes in the house and the second for the hot water tank. When you leave, turn off the house valve and open the other 2 valves. Everything will drain by itself.

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