36

Yeah, it sounds like you got backsiphoned Most houses in the US don't have any protection against their municipal water service going negative pressure and backsiphoning any garbage present at outlet points into them. Even if you have lawn irrigation, the vacuum breaker for that only prevents the irrigation system from contaminating things, not your whole ...


33

Unless you go to more expensive industrial products, you'll have trouble finding thermostats that operate reliably at near freezing temperatures. Using a space heater to heat up the entire crawl space is going to be inefficient when all you need is to keep the pipes above freezing. Heat tape seems like a much better option, it's made for this exact purpose. ...


30

No, you can't do anything like that at all. That's a suicide cord. Meaning it has 2 plugs on it, and in certain conditions the prongs of one can be unplugged and live. Nothing should ever have 2 plugs. Remove the "plug-in thermostats" from the equation - they're cheap anyway. Use hardwired thermostats -- those can be paralleled in the manner you ...


15

What I would do ( have done) is replace the elbow with a "T" and add a valve to be opened in winter . Presumably the valve will be below grade and will need something like a sprinkler valve box. I have a few similar drain valves in my sprinkler system.


12

The reason it bursts is because inside the tap is a non-return valve which is required to comply with water regulations. The valve stops the tap draining. In this instance it is better to fit a tap without the non-return valve and instead fit a separate on inside the property next to your isolating valve. Your plumber will be able to do this when he repairs ...


11

It's all about the temperature/pressure relationship, and how pressure affects the boiling point of the refrigerant. As the pressure of a refrigerant goes up, so too does the temperature and boiling point. When the pressure drops, the temperature and boiling point drop as well. Air conditioning (and some heating) systems take advantage of this, to cool (heat)...


11

It should not be possible to fully drain your water tank unless you use the drain valve and tilt the unit. The lowest the water can go is the bottom of the cold water pipe. Notice the blue line I added to the image. However if your heater is still heating then it could evaporate all of the water and cause premature death for your water heater. Notice both ...


10

Your plan is OK except that -20C is about the lowest you are going to get protection with NaCl (i.e. common salt). Here is a graph of freeze point vs. concentration. You really cannot get a higher concentration than about 23% since excess salt precipitates out. I think you'll be better off using an anti-freeze product.


8

Your plumber seems to be poorly educated if you are left without the following solutions having been mentioned. This is pretty standard problem for folks with a boiler AND a woodstove - the woodstove keeps the house warm and the boiler pipes are subject to freezing off in the corners of the house. Not that this is your situation, but a "standard" solution ...


8

I think you answered your own question: They do have pipe insulation on them (though due to my own stupidity the insulation on the place that burst had fallen off and I hadn't replaced it.) The pipe insulation on the rest of the system worked as it should. The only reported failure was where there was not insulation. This suggests to me that the ...


7

Shutting off and draining the water is a good idea. If for no reason other than an unnoticed leak could cause considerable damage. Don't forget the water heater and fridge if it has an icemaker since the power is off. Also the toilets, flush them after you have the water off. Then use a large sponge to sop up the water in the bottom of the bowl. Dip the ...


7

Not sure if this is applicable, but here in the US we have something called "yard hydrants". The weather were I live (western Washington state) is similar to the UK. The taps are controlled by a rod to the valve which is substantially below ground level. Not only that, they have a drain that drains the upper part into the ground when the valve ...


6

Chlorodifluoromethane, also known as R22 refrigerant has a boiling point of -40°F at 0 psi. As you increase the pressure of the refrigerant, the boiling point also increases. At 68.5 psi, the boiling point of R22 is 40°F. In a normally functioning system, the refrigerant is sent into the evaporator at about 55-65 psi. Which means that the boiling ...


5

The bursting is actually caused by the ice. Ice takes up more room than the amount of water it was made from, ultimately bursting through copper. If you had a trickle of water, you may have been better off leaving the taps all open in hopes of keeping the water flowing. Flowing water (even a trickle) is less likely to freeze than standing water. One of the ...


5

If it's a metal/copper pipe, you could wrap the exposed portion of the pipe in heat tape to help speed the thaw. Since metal and water are good conductors of heat, the heat from the tape will spread fairly quickly down the pipe. Or even just use a hair dryer. Not as efficient or quick, but still helpful.


5

I agree with the comment in that its surprising the copper pipe would conduct enough heat to freeze the downstream pipe, are you sure there's not a draft or something like that? Your idea to isolate the pipe seems relatively sound though. You would likely want to use PEX instead of PVC. PEX normally requires a special tool to crimp the connectors, so I ...


5

The key question would be: How many winters has this pipe been like this and lasted without bursting? If it has made it through for many years, it should probably be good for many more. Does it have an indoor valve where you can turn it off and drain the water, similar to this: http://www.homedepot.com/p/Everbilt-3-4-in-Brass-Sweat-x-Sweat-Ball-and-Waste-...


5

It seems to me the biggest problem is if your heater doesn't turn on and you don't know about it, right? If it fails to turn on but you do know about it, you can address the problem. As such, if it were me I'd consider this a "good" use for home automation. I'd get a plug that could connect to my network (either directly or via a hub) and have ...


5

What's available here in the UK may be a bit different to what you can get, but this might guide you a bit. We have mains-rated thermostats designed to bring on gas-fired heating systems and protect the system and building from frost (called frost stats). That's what you're trying to do. These are strictly for hardwiring, are are only suitable for ...


4

Heat pump? Keep salt away from the unit. Salt will attack and totally decompose the fins and will create electrolytic corrosion in the joints between aluminum and copper leading to destruction of the system. Icing during operation in a damp climate is normal, it's supposed to have a defrost cycle it runs through to remove the ice. Heat Pump Operation: ...


4

Run the pump. If you have a pool cover, put it on. The pool itself stores a lot of heat. Moving water is much harder to freeze than water standing still.


4

It sounds to me like the defrost heaters are not turning off. I can not tell you if yours uses a thermal switch or a timer to cycle them, my guess is for a mechanical switch not working anymore, and stuck in the on position. I am going for the idea that the repair guy thought nothing about the hot sides/top, because it is normal for it to happen, and he ...


4

I eventually fixed the problem, and it turned out to be insufficient water flow to the icemaker. The ice maker was being fed via a clamp-on saddle valve. I closed that off, disconnected it, and soldered in a 1/4" brass line with a 'proper' shut off valve. That provided plenty of flow rate, and since then the icemaker has been working flawlessly.


4

If the cold water supply to the water heater is frozen, there's not going to be much/any pressure to push water through. Typical mobile home freezup is the supply line to the mobile home, not as much the pipes inside the mobile home. The three feet or so between the floor and the ground is a prime area for freezing and usually requires insulation and heat ...


4

This question is about thermal mass/intertia. Suppose you are doing solar panels. The solar energy (from the panel's perspective) is exactly the same 1 hour after sunrise versus 1 hour before sunset. So why is the house so darn cold in the morning and hot in the evening? Because it takes time for temperature to change. Heat energy has to actually move,...


4

This depends on the particular house - both how the plumbing is laid out (are water pipes located in exterior walls, or not?) and the relationship between heat delivery and plumbing. It may also depend on the heating system - i.e. hot water baseboards often have pipes that run in poorly insulated spaces at the edges of the house, and can themselves freeze ...


4

There are a few causes for this, and the most common are in two categories - bad air flow and low refrigerant. Bad airflow can be caused by a dirty filter, clogged ducts, or a poorly performing fan. If the (relatively) warm air from your house isn't blowing over the coils, the condensation they normally create starts to freeze. Once they start to freeze, ...


4

it may be possible to put insulation in such that the pipe is insulated from the outside/crawlspace but not from the house. That way, the heat from the house will keep the pipes warm. I had to do this in my house. The foam insulation guy sprayed foam onto the underside of the floor and left the water pipe exposed. The pipe that never froze started freezing. ...


4

If the indoor valve is higher up or lower down than the outdoor valve without a vertical u shape in the pipe, the outdoor valve, you can install a plug indoors downstream of the indoor valve. Before the cold season, close the indoor valve, open the outdoor valve and remove the plug to drain. If it can't naturally drain you can use a wet/dry vac on suck ...


3

What you have done sounds like a good start. Some additional steps I would take on the coldest nights is to allow the faucet to drip. You want it to drip as slowly as you can. Moving water takes longer to freeze than still water. In addition leave the cabinet doors open so that some of the kitchen heat will warm the pipes in the cabinet. Again these are ...


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