Beware eBay Chinese products

 My home is what is known as 'off-grid.'

My electrical energy comes from a solar power installation, and two generators.

I collect rain water into two, 250 gallon IBC containers. There is a shallow well jet pump to deliver the water. PEX tubing replaced the cpvc plumbing which, in turn, replaced the steel/iron/copper plumbing. The A version is used with a DeWalt, battery powered, expansion tool. The plumbing consists of grade A products, except for one.

I decided to use an on-demand , propane powered, tankless water heater instead of the traditional electric model. My electric model sat for several years in my basement without use.

The water heater I chose was a brandless Chinese model on eBay. The price was around a hundred dollars. Fast forward one year and the intake fitting breaks. This indicates a cheap alloy was used. The fitting was the only component that had a weakness in design. The fitting is a threaded portion as part of a tube with another threaded portion on the other end. The fitting was attached to a PEX 1/2" tub with 1/2" NPT fitting and CPVC adapter. The CPVC is rigid and may be the reason the failure occurred. vibration and small movements over a year may have fatigued the metal to the point a break occurred.

The solution?

Two:

1. If the metric thread standard was used, a replacement can be built from parts ordered online.

2. A repair tool such as J.B. Weld can be used to reconnect the two pieces of the fitting, and to add reinforcement for future stress events.

The water heater has tempurature regulation problems. If the water flow slows, the heat raises the temp of the water. For some reason, after a year, the average temperature level has increased.

Plumbing leaks could reduce flow. I've had issues with a 'compatible' PEX product.

Build up of material in the inlet or outlet could restict flow, thereby increasing temperature.

To make a long story short, I also purchased a two year warranty from SquareTrade(Allstate) at the same time. After communicating with a representative, I am being sent a paper check in the mail to arrive within five days. The warranty covers the cost of the unit. Typically, these nits, on eBay, have free shipping, so there is no cost there.

I can, at my pleasure, buy a replacement unit, at no additional cost to me, or repair the existing unit and continue using the unit. Or both.

If you purchase a critical item or an expensive item, on eBay, also purchase a warranty if available.

Update: I purchased a used/older Rennai on demand water heater from a local store that sells second hand building materials and appliances. The unit was natural gas based but I bought and installed a propane conversion unit. The unit is in the bathroom and has replaced the Chinese unit.

I moved the Chinese unit to the kitchen and now have hot and cold running water in both places. Repair of the unit seems to require replacement of a rubber diaphragm used in a temperature control device. I have some online sources but haven't decided whether to just buy a new unit, maybe a more expensive, smaller, name brand unit.

Note, there are good and reliable products from China, but the proliferation of cheaply made goods makes buying risky. Consider repairs. Where? If you diy repairs, where do you get parts, drawings? A good reason to buy known brands with reasonable and available service resources.