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PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR
ANTIFREEZE for BOILERS
BACKUP PREVENTION, SEWER LINE
BLOCKED DRAIN REPAIR METHODS
CLEANOUTS, PLUMBING DRAIN
CLOGGED DRAIN DIAGNOSIS & REPAIR
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
HEAT TAPE USAGE GUIDE
HOT WATER HEATERS
INSULATION INSPECTION & IMPROVEMENT
NO HEAT - BOILER
NO HEAT - FURNACE
ODORS GASES SMELLS, DIAGNOSIS & CURE
OIL FIRED WATER HEATERS
PIPING IN buildings, Clogs Leaks Types
PLUMBING FIXTURES, KITCHEN, BATH
PUMPS, PONY PUMPS
RELIEF VALVE LEAKS
SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SHUTOFF VALVE LOCATION, USE
SUMP PUMPS GUIDE
TRAPS on PLUMBING FIXTURES
WATER HEATER PROBLEM DIAGNOSIS
WATER HEATER COMPARISONS, PROPERTIES
WATER, WELLS, WATER TANKS: TESTING GUIDE
WATER SHUTOFF VALVE LOCATION, USE
WATER SHUTOFF VALVE, WELL PUMP
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WELLS CISTERNS & SPRINGS
WINTERIZE A BUILDING
Winterizing a building: how to freeze proof a building when heat will be turned off:
This article explains with a step by step guide just how to winterize or freeze proof a building when the building's heating system is going to be turned off completely.
We discuss turning off water supply, draining piping and plumbing fixtures, turning off and if necessary winterizing a heating system, and other steps to avoid freeze damage or water, leaks, and mold damage to buildings that are being left in a "shut down" condition.
The articles at this website will answer most questions about freeze protection for piping and other building plumbing and heating system components: how to winterize a building to avoid frozen pipes, and how to thaw frozen water supply & drain piping, wells, & water tanks.
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[Click to enlarge any image] Sketch at left courtesy of Carson Dunlop Associates.
If you have decided to shut down the building's heating system, some steps to protect the building from freeze damage are simple (you don't worry about figuring out the thermostat set-temperature nor about finding "cold spots" where pipes may freeze).
But other critical steps need to be performed if you are going to avoid frozen pipes and future leaks and water damage in a building to be winterized with the heat left off (such as an empty summer cabin, vacation home, or an unoccupied residence.)
See details at WINTERIZE WATER SOFTENER & WATER TREATMENT EQUIPMENT.
at DRAIN FREEZE PROTECTION which was discussed under the "heat-on" winterization notes. Further steps include removing traps and use of a non-toxic antifreeze in traps or toilets that cannot easily be removed or emptied of all water.
Empty or remove building fixture traps; see our note below about use of antifreeze.
Use of antifreeze to winterize a building: Be careful: unless the anti-freeze is specifically designed for winterizing a building it could be highly toxic (such as automobile antifreeze).
We do not recommend using toxic antifreeze to winterize a building since later you're moving that contaminant into the public sewer or into soils (and possibly ground water) around a private septic system. Only inside of closed water systems such as a heating boiler do we recommend use of anti-freeze mix in a building.
Protect well piping from freezing: If your water supply system's piping is not below the frost line your water system should include protection against well or lake water freeze-ups. But sometimes a building's water supply piping that has never frozen before will freeze when no water is run during long periods of freezing weather.
See SNIFTER & DRAIN BACK VALVES
This sketch of a gas-fired water heater and its control valves is provided courtesy of Carson Dunlop Associates.
Heating an empty water tank is very dangerous and is likely to quickly destroy the tank or its heating elements.
Reader Question: How can we test for possible foundation damage if we leave our home with heat off completely?
We built our home 15 years ago. It is a split level with concrete foundation. When we retired we stated to spend our winters in a warmer climate (we live in N. Ontario). Every winter we have left some heat on the lower level of the house keeping the temperature around 4c.
However with the increase in the cost of oil and our dwindling income buying power, we have been thinking of ways we could cut off both the hydro and the oil heater. Is there any way of us testing what effect this might have on the concrete foundations?
The foundation is covered with a layer of ceramic tiles which we later covered over with a laminate flooring. Thank you. - C.W., northern Ontario
Our sketch (left, courtesy of Carson Dunlop Associates) shows what happens when a home is left with heat off in a freezing climate.
Reply: Tests for possible frost damage to foundations? try these local research topics
I don't know of an actual test that you can perform to predict foundation damage if the heat is left off completely in your building, since testing would require creating the actual freezing conditions and would itself risk building damage. Sketch at left, showing evidence of frost heaving is provided courtesy of Carson Dunlop Associates.
At "A Common Source of Vertical Frost Heave - Un-heated Homes" found in our article
And at Frost Heave/Expansive Soil Cracks in Slabs we provide more details.
Sketch (left, courtesy of Carson Dunlop Associates) shows upwards as well as horizontal frost pressure on a building and it indicates where cracks and dislocation commonly appear.
Here are some things you can check:
Watch out: other factors can still cause slab or foundation damage due to frost.
Other Steps to Reduce the Cost of Heating Left On to Avoid Frost Damage
An alternative to turning heat off in the building entirely is to continue your practice of leaving heat on at a low setting (4 C or about 40 F) but take measures to protect the building from damage (possibly allowing a slightly lower heat setting) and to reduce heating cost by finding and fixing drafts, air leaks, or by improving building insulation.
Continue reading at ANTIFREEZE for BOILERS or select a topic from the More Reading links shown below.
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Frequently Asked Questions (FAQs)
Question: Winterizing the heating system: Is it OK to drain un-used heating zone piping, baseboards and radiators?
I have a boiler with 5 heating zones. I am living alone in a big house and do not use the rooms for 3 of the zones. I would like to know if I can drain those zones so they don't freeze and just use the 2 remaining zones for heat.
Sure, provided your heating zones are individual piping loops, and that you have control valves at both ends of the un-used heating zones, you can drain them and leave them turned off.
At AIR BLEEDER VALVES we describe air bleed valves found on hot water heating systems. These valves, normally used to purge trapped air that can cause cold radiators or baseboards, can also be opened to make it easier to get water out of the heating system piping when the building is being drained so as to leave heat off completely.
Watch out to get all of the water out of the piping. It can be difficult to get water out of long horizontal pipe runs without blowing air through the system. For this reason some winterizing companies actually cut the heating pipes, planning to repair them when the building heat is restored. Don't forget to check for cut or burst heating pipes later when de-winterizing the building.
Question: Winterizing the heating system: Can I put antifreeze in the heating system instead of draining it?
I've read the other parts of your website as you suggested and I hope you don't mind more questions. Instead of trying to drain the heating zones I don't need, can I just put a non-toxic antifreeze in the whole boiler system? It sounds easier if it is a good solution.
Reply: use an antifreeze intended for use in heating boilers and piping
Sure, there are specific antifreeze products intended for use in hot water heating systems.
Question: Winterizing the heating system:Can I shut off the first radiators in the heating zone without losing heat in the rest of the house?
I have such a system, and only one zone. The thermostat is located in the warmest room in the house. Causing frigidity and numbness of extremities in other areas of the home. Since the location of the thermostat is also where the first radiator is in the home, can I "shut off" that baseboard radiator, and the next one, without losing heat to the rest of the home? - Jacke
Reply: It depends ... on how heating piping is arranged
Question: How to Add antifreeze for hot water heating piping
how do i add antifreeze to my boilers baseboard heating system - Gene Griswold 7/22/12
Gene, please search InspectApedia for
Question: emergency steps to avoid freeze damage
(Jan 28, 2014) Tracy said:
Review the checklist at
the link is at the top of this article.
At a bare minimum: if you expect power to be off, turn off the building water supply.
Then on return to the home go through our De-Winterizing checklist - basically you will turn heat on and water on and check for leaks.
Question: some heat left on to avoid interior cracks
(Nov 5, 2014) Deborah Frenette said:
Yes Deborah, in extreme cold some building materials may show signs of cracking or movement. I've seen this show up as drywall cracks and on a few occasions fine cracks in ceramic tile floors on a concrete slab. For this reason, while it is still possible and even reasonable to leave heat off completely (with proper winterizing) for modern construction and where a building is not being left for an extended period such that we are trying to eliminate heating costs completely, I prefer to keep some low heat in the building to try to keep it a bit above freezing.
(Nov 5, 2014) Deborah said:
You might see no cracking at all - a lot depends on the particular details of construction including materials, connectors, foundation type, basement vs slab, and importantly, water under and around the building.
If the building is more than a decade old you might have some clues by noting whether or not settlemnt or other cracking has ever occurred.
Question: antifreeze for traps and toilets vs. environmental contamination
(Jan 14, 2015) Anonymous said:
(Feb 3, 2015) Crafty said:
Crafty there are food grade antifreeze products used in RVs and water systems. Those products should not be harmful. If you let visitors use whatever they bring we've lost control of the problem and may be killing off the septic system to boot.
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