Will RV antifreeze melt ice? (how to defrost RV pipes)

In this article, we will discuss: Will RV antifreeze melt ice? We will explain how to defrost RV pipes and how to use the RV water system safely even on cold winter days. 

Will RV antifreeze melt ice?

Yes, RV antifreeze can melt ice, and here’s how to do it:

  1. Prepare the area that you are going to work. Try to remove as much ice as possible – you can even use hot water to melt some of it before applying the antifreeze.
  1. Make sure you have the correct type of antifreeze. RV antifreeze is usually sold at discount stores or RV dealerships, but it is also found at hardware stores or auto parts stores. It is usually pink in colour and can be made up of ethanol or propylene glycol, or a mixture of both. 
  1. Following the manufacturer’s instructions, apply the antifreeze on the needed area. Most RV antifreeze brands promise that they can melt ice at temperatures as low as -45 C degrees, but you must know that some brands are better than others.
  1. If you don’t see results in the first few seconds, dilute the antifreeze with water so you have more liquid to get the job done.

And that is it, you should have managed to melt the ice by now!

How to defrost and empty an RV holding tank?

An RV holding tank contains fresh and residual water. If the temperature is cold enough, the water will freeze under normal circumstances, but the RV’s radiator has antifreeze to prevent this. Of course, this is toxic and freshwater should never be mixed with your RV’s antifreeze.

There are three RV holding tanks: cool, black, and grey. These are for drinking water, toilet water, and kitchen sink water. Let’s see how to defrost and empty an RV holding tank.

Step 1 – Preparation

First, the RV must be covered so that the temperature is above zero. You will need a properly covered area, for example, a large garage and the ability to access the underside of the vehicle. Put on your safety glasses and gloves to protect your eyes and hands.

Step 2 – locate the tank

Check your RV manual for the location of these holding tanks. They are usually located under the RV and are very close together.

Step 3 – Clean the tank

Clean any accumulated debris from the RV holding tank. You can use warm soapy water and cloth for this purpose.

Step 4 – Provide heat

Plugin the blow dryer or blow dryer and direct the hot air into the RV holding tank. Maintain 6 to 12 inches of the holding tank and keep moving the dryer back and forth, up and down, in a slow but steady sweeping motion. Be careful not to stay in one place for too long as this could damage or melt the plastic material in the tank and pipes. Do not allow the dryer to overheat.

Step 5 – Verify

While doing this, check that the ice that has formed in the tank has not divided the tank or the pipes connecting it and that they are not damaged or leaking. Check that the circlips connecting the pipes to the tanks are completely tight and undamaged.

If the RV’s holding tank or any of the connections or pipes have been damaged, they will need to be replaced, as repairs are generally not possible. If this is the case, stop the attempt to defrost the tank or tanks and buy replacements; then you can separate the faulty items and replace them. Once this is complete, continue defrosting any tanks that still need attention.

Repeat this process for each of the three holding tanks.

Step 6 – Empty unfrozen holding tanks

Once the tanks are thawed, drive to an RV waste dump station. Empty each one in this order: first black, then grey, then finally the stale fresh water.

Step 7 – Replace

Replace it with water and a non-toxic additive that acts like antifreeze and is commonly available – the bio-based additive is safe for humans. Add to each holding tank. This should ensure that although temperatures may remain below freezing, each RV holding tank will remain ice-free and fully functional.

How to protect the RV plumbing from freezing

There are two possible techniques for winterizing your plumbing: A. The method without an air compressor and B. The method with an air compressor. In my opinion, method B is the easiest but requires you to buy an air compressor, which is an additional investment of over $200.

  1. If you don’t have an air compressor: 
  1. First empty the tanks and the water heater of your caravan, including the three tanks (fresh, grey and black water). Rinse thoroughly to make sure there is no waste.
  1. Under the RV, unscrew the drain plugs (if you have one) and turn on all sink and sink faucets, indoor and outdoor showers. Let the water run, then close the caps and taps.
  1. You need to put antifreeze in the pipes of your vehicle. Use non-toxic RV antifreeze, which is designed for temperatures down to -45 ° C. Never use automotive radiator antifreeze, which is poisonous. Approximately 8 litres (2 gallons) will be needed at this step. Each gallon of plastic pipe antifreeze costs approx. $ 4.
  1. Prevent antifreeze from entering the water heater tank by operating the water heater bypass valve (place in Winter mode).
  1. To drain the water heater, unscrew the cap located at the bottom of the tank on the outside, with a 1 1/16 inch wrench. To facilitate the flow of water, open the safety valve located at the top of the tank. Run water to remove lime deposits and rinse thoroughly. Secure the item.
  1. Plugin the water pump hose and insert it into the gallon of antifreeze to suck the red liquid into the plumbing of your trailer. If the pump is difficult to access, the antifreeze can be poured directly into the fresh water tank.
  1. When step 6 is complete, activate the pump by opening all faucets and showers, until the water is drained. You will then see the completely red antifreeze flowing. Technically, then there will be no water in your pipes.
  1. Pour approximately 225 ml (1 cup) of antifreeze in each of the elbows (P Trap) to remove the remaining water. (including toilet, shower, sink and kitchen sink drains).
  1. Last step: Open all the drain hose plugs to drain the water remaining from the procedure. Don’t forget to close them after this step.

B. If you have an air compressor: 

  1. At an RV centre, get an air compressor water inlet purge adapter (approx. $ 5). Screw it into the water inlet.
  1. Drain the fresh water tank as well as the grey and black water tanks.
  1. Empty the water heater. Unscrew the cap located at the bottom of the tank on the outside, with a 1 1/16 inch wrench. To facilitate the flow of water, you can open the safety valve located at the top of the tank. Run water to remove lime deposits and rinse thoroughly. Secure the item.
  1. Open all faucets, including the showerhead, the flush device, and any water lines that are closed.
  1. Run the water pump for 30 seconds to drain all the water from the pipes. Close the pump.
  1. Connect the air hose from the compressor to the adapter referred to at the water inlet.
  1. Adjust the compressor not to exceed 30 pounds of pressure and blow the water lines until water is no longer flowing from the faucets. Make sure to turn on one faucet at a time to drain everything. You will need help inside to confirm that the air is coming out of the faucets.
  1. Pour non-toxic antifreeze in all drains (P Trap), elbows, toilets and reservoirs.

If all of the above procedures scare you, you can ask your dealer to do them for you, at a flat rate. And then you can hibernate in your cave, until spring.

If we can be of any further help, please let us know!

FAQ on Will RV antifreeze melt ice?

Does RV antifreeze freeze?

RV antifreeze does not freeze that easily. It can be safely used at minus 45 degrees C (-50 degrees F). Minus 12 or more degrees to that, the RV antifreeze could start freezing. 

Can I use my RV toilet in the winter?

Yes, you can use your RV toilet in winter, however, there are certain precautions to take in order to prevent wastewater from freezing, especially on those cold, cold nights.  

Do I need RV antifreeze?

You need RV antifreeze. Internal combustion engines generate heat during operation, which reduces engine performance. To avoid this, cars have a cooling circuit that dissipates part of this heat to the outside.


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