Homemade Heat Pump Water Heater (R290)

Mikesolar · 11-28-12, 10:24 AM

Quote from one of the UK guys who seems to know:

"Purity

The quality of commercially available propane (LPG) is very often
not suitable for refrigeration. The composition varies substantially,
generally having between 60 and 95% propane. It can have high
levels of moisture and unsaturated hydrocarbons.
Impurities such as other hydrocarbons can impact the vapour
pressure of the product, lowering overall system efficiency. Sulphur
can cause corrosion, and unsaturated hydrocarbons can react with
system components. Moisture leads to hydrolysis, corrosion and
compressor failure.

R290 is at least 97.5% pure with minimal levels of critical impurities including moisture
(typically† <10ppm), unsaturated hydrocarbons (typically <0.5%) and
sulphur. This makes it ideal for use in all types of refrigeration and air
conditioning systems."

Maybe all that is needed is to run it through a proper filter system to meet the requirements? That is something else to be checked out.

11-28-12, 10:24 AM	#9
Mikesolar Master EcoRenovator Join Date: Aug 2012 Location: Toronto Posts: 958 Thanks: 40 Thanked 158 Times in 150 Posts	Quote from one of the UK guys who seems to know: "Purity The quality of commercially available propane (LPG) is very often not suitable for refrigeration. The composition varies substantially, generally having between 60 and 95% propane. It can have high levels of moisture and unsaturated hydrocarbons. Impurities such as other hydrocarbons can impact the vapour pressure of the product, lowering overall system efficiency. Sulphur can cause corrosion, and unsaturated hydrocarbons can react with system components. Moisture leads to hydrolysis, corrosion and compressor failure. R290 is at least 97.5% pure with minimal levels of critical impurities including moisture (typically† <10ppm), unsaturated hydrocarbons (typically <0.5%) and sulphur. This makes it ideal for use in all types of refrigeration and air conditioning systems." Maybe all that is needed is to run it through a proper filter system to meet the requirements? That is something else to be checked out.