Drain hot water heating system for the winter?

[Tom B.]

I go to Florida in the winter. My house in Minnesota has hot water heat (natural gas) and a "boiler" with 3 zone valves that are less than 10 years old heating 2400 sq. ft. It has mercury thermostats that are also just a few years old. Last winter our gas bills were as high as $200 a month even though the thermostats are all the way down (55 degrees). This year they will be higher. I've read threads about antifreeze in the hot water heating system (sounds like there can be problems) and I realize I could close the house (drain plumbing and hot water system) but I've heard horror stories about walls cracking, etc. (it can get down to -40 here!). Someone told me to tilt the thermostats to get below 55 but this seems difficult to control.

Any ideas on how I could save some money this winter? I'm certainly willing to spend some money to save some.

Thanks in advance.

[MikeM]

We don't get that cold here... but we regularly drain houses and heating systems of homes that will be vacant for the winter. Turn water off, flush everything, turn all faucets on, drain everything, remove the water meter (if you can), blow water and heating lines out with air, treat with non-toxic antifreeze a bit, treat traps with anti-freeze along with the washing machine pump... don't forget to remove the dishwasher solenoid, washing machine hoses, drain spray hoses connected to faucets ...

You'll have to look around and think like water :-)

AS for all the other damage you mention - I have not seen it but like I said it doesn't get that cold here.

Mike

[Dan]

It's possible to put anit-freeze in the boiler water and run at a lower temperature but there are risks. Condensation is likely to be a problem inside the boiler causing corrosion. A small leak could result in the treated water gradually being replaced by city water. You can have problems draining the system too, it's difficult to get all the water out, a low spot may result in breaks.

[MLD]

Be careful who does the job for you. Friend in Maine had the same thing done only it wasn't done properly. Got a call to come back from Florida in the middle of the winter. Water everywhere, basically the whole inside of the house (two floors) was gone--walls, furniture appliances, everything. Result was that the whole inside was gutted and had to be reconstructed--at least a 6 month job. Furniture replacement was so extensive that they actually went to N.C. and purchased a whole houseload of stuff from one of the furniture factories. The furniture company used their own trucks to ship and had their own people along to set it all up. Horror story but sh*t happens. MLD

[wayne]

one simple trick for thermostats is a small light bulb under the thermostat that will make it think it is warmer than it is. You will need to play with it. You don't mention floors wood floors would not like going from 30 degrees back to 68 quickly when you came home. I would shut the valve off to the hot water tank if you can cover the windows as much as you can. how much ceiling insulation do you have?

I would not try to leave the house unheated you would need to make sure you have no liquids in cans bottles etc.. that would freeze and burst.

Wayne

[Paul Franklin]

Perhaps new digital thermostats would allow you to set the temperature lower than 55? My Honeywell's go down at least to 45. I wouldn't cut it too close to freezing, but that should save you a lot of money.

I would still be inclined to drain the regular plumbing (not the heating system) just to prevent any chance of a pipe freezing in a wall where proximity to the outside or a gap in the insulation can cause a local cold spot.

HTH,

Paul

[Joe Bobst]

Based on a bad experience in our family, I would positively NOT screw around with an effective operating system. Just get some top quality programable thermosts, set them at 50-55 degrees and that will be the safest setting in your area. When you close up the house arrange for someone to check it for you daily. And have some way of documenting the house check, like a signed work sheet. If you don't, and there is any freezing damage your insurance company will weasel out of compensating your loss by invoking their "unoccupied residence" clause. Bottom line, it is probably much more realistic to keep things running normally than squeezing a few dollars out of the fuel bill. HTH

Joe

[toller]

Dishwasher solenoid? What is that? My dishwasher winterizing routine is to disconnect the inlet, get as much water out of the sump as I can with a sponge and put some antifreeze in. Am I missing the solenoid?

[Chet Hayes]

If the furnace is going to be left on, why would he need any anti-freeze in the boiler at all? With too low a temp you run the risk of things like cold water pipes in exterior walls freezing, but how can the heating pipes themselves freeze. When it's real cold outside, the furnace will be running more often and that's surely enough to keep the heating system itself from freezing.

[Dan]

We're discussing a zoned system, at low temperatures it's likely that one zone will provide enough heat that the other will come on seldom if at all. Since heating pipes are often on outside walls, freezing in one zone is likely. I've seen it before, but I guess you know better! Since it's not my house, or repair cost, I'll defer to your superior knowledge.

[Chris Hill]

Rent the house. Your insurance probably won't cover an unoccupied house.