
In a standard size home, you’ll usually find a gigantic water heater gargling in the basement. In a Tiny Home, you have to think… well…. tinier. Today, I’m going to talk about my Tiny House water heater choice, and how I made a big mistake during winter.
My Tiny House Water Heater
My Tiny House water heater is the PrecisionTemp RV-550 NSP. There are a couple of special features to this particular instant propane water heater that makes it the best choice for Tiny Homes.
***NEW DISCOUNT! When you purchase through the PercisionTemp website, enter coupon code “GIANT” at check out to receive $25 off. Total price is $75 cheaper than purchasing through Amazon!***
PROS of the PercisionTemp Tiny House Water Heater:
- Water Temperature Rise. The PercisionTemp has an 88° F temperature rise per gallon per minute. That’s impressive and uncommon for such a tiny unit.
- Limitless, (Almost) Instant Hot Water. The PercisionTemp is capable of heating water within 10 seconds, limitlessly. Other instant units take up to 45 seconds to heat water.
- Compact. The PercisionTemp is a small 14″ cube. It fits easily under my kitchen counter.
- Floor Vent. As with all propane units, the PercisionTemp requires exterior ventilation, but this unit actually vents through the floor! That means you don’t need to cut a hole in the side of your Tiny House (which can be unattractive).
- Anti-Freezing Protection. The PercisionTemp will detect when it’s about to freeze and start to protect itself. Keep in mind, freezing your unit is not covered under warranty (read on for how I managed to screw this up).
- Uses almost no electricity. A small amount of electricity is required to ignite the unit. This is common with propane appliances. A 12-volt battery is sufficient. I can use this unit while running on solar power, which was ideal for my situation.
CONS of the PercisionTemp Tiny House Water Heater:
- Expensive. The PercisionTemp retails at $1,150, making it one of the most expensive Tiny House water heaters on the market.
- 5-10 Seconds to Heat Up. Even though 10 seconds is not a long time to heat water, a tank water heater would be absolutely instant (though limited by the tank size). When I shower, I like to take navy showers – meaning I turn the water off as I lather up. Every time I turn the water back on, I endure 5-10 seconds of cold water before the hot water kicks in. It’s not exactly a spa shower, but it’s efficient and eco-friendly.
*For a list of my recommended Tiny House plumbing materials, click here
How I broke my Tiny House water heater from a stupid mistake!
This past winter was my first real winter in the Tiny House. I parked my Tiny House in the Colorado Rockies – one of the coldest places in the USA. Usually, I keep the house warm, but from November to December I left the house unattended as I traveled to Europe. I didn’t winterize the Tiny House, because I was hoping my Envi heater would keep it from freezing while I was away. That was a mistake.
In late November, nightly temperatures dropped to below 0°F. My Envi heater couldn’t keep up and the internal house temperature dropped to below freezing (32°F). My water heater tried to trigger itself to ignite to prevent itself from freezing but failed. The trouble was, my propane tanks were freezing as well. At the time, I didn’t protect my tanks with heat blankets so their efficiency was significantly reduced. My PercisionTemp was not receiving enough propane pressure to ignite, and eventually, the pipes inside the unit froze and burst. Water from my tank emptied through the water heater unto the ground beneath my trailer. Luckily, my house did not flood (thanks to the water heater’s floor venting).

When I returned from my trip, I found the issue and purchased a few parts from PrecisionTemp to fix the heater. The total damage was $235 (plus shipping). Ouch.
This mistake could have been prevented a number of ways:
- Occupants. Had I been around, the problem would have been noticed and rectified before the pipes froze.
- Winterizing the unit. I could have drained the unit and filled my plumbing with antifreeze.
- Propane blanket. Had I purchased a propane heat blanket before I left, the pressure would have been enough to keep the water heater from freezing. My propane efficiency increases dramatically with the help of the blanket.
Which water heater are you going to use in your Tiny House?
Other Articles You Might Be Interested In:
- The Best Compost Toilet for Tiny Houses
- Tiny House Plumbing: And Easy Set Up (With Video)
- 10 Products For Tiny House Winter Living
- Cold Climate Prep for Tiny Homes
- 10 Products to Green Your Greywater
Receive $25 off when using the coupon code “GIANT” at check out. You save $75 total off of the Amazon price, and I will receive a smallcommissionn for the sale.
Hi! Wondering how things have been with this hot water heater in the over-a-year since you made this post. Have you heard of anything more affordable that would serve your needs? My tiny home will heat with wood, meaning there is the danger of freezing temps when I’m not there, so same issue as you are facing. Any more thoughts on your choice and alternatives are welcome and appreciated!
Author
I still love my water heater. And, actually, I installed the new version of this same heater in February of 2016. It works even better now! It’s quieter and it heats up more rapidly. I’m not sure the new version is officially on the market yet. You may need to call the company. I still highly recommend it when it comes to propane, tankless, instant water heaters for Tiny Houses. Otherwise, if you want cheaper, I would go with a tank water heater. Those have their downsides though – such as limited hot water.
How long (on adverage) would you say you have to refill your propane tanks? And what, if anything, else do you run off your tanks? We are going to use propane exclusively for our water heater and cant seem to figure out how often we will need to refill a 20 gal tank.
Lb**
Author
When I’m just using the propane water heater and my propane stove top, I would replace my two 15lb tanks about every 6 weeks. When I’m also using my fridge on propane (it does both electric and propane), it goes in about half the time.
A person’s profession and income generation and their preferred lifestyle need not differ: Jenna and Guillaume have masterfully created a life for themselves that does both!
Their choice to live simply and be mobile is chosen carefully to enhance their lives and reach their goals. A non-mobile house “set in the back woods” is at odds with their lifestyle, and doesn’t compare.
Congratulations on your success, Jenna and Guillaume! 🙂 Many admire your achievement, despite the envy of these dissenters of the (mobile) tiny house movement.