What is the different of non pressure and high pressure solar water heater?

This is a very good question, when new buyer start to learn and wannt buy one solar water heater for their home, how to size the right type solar water heater at durable/afforable/bankable way?
follow riwatt solar, let’s check more the 6 main difference  together!


1. Material difference

Non pressure solar water heater is open loop system, inner tank basically is 0.28~ 0.7mm thickness, majority are 0.31/0.38/0.45mm thickness,
while, high pressure solar water heater is closed loop solar heater, with inner tank range from 1.0mm to 1.5mm thickness, high pressure adopt better material than non pressure from this point.

2.Pressure Difference

Non pressure solar water heater bear lower pressure, Max. 0.05MPA, while, high pressure solar water heater can bear 0.7Mpa,
solar water heater can installed anywhere you wanna, while, non pressure, it is GRAVITY FEED solar system, the shower pressure are mainly depend on the water gravity,
thus, we must install the water heater at least 2 to 3 meters higher than your shower room, and make sure, smoothly pipeline connection instead of too much elbow fittings
appearently, high pressure solar heater will make our shower time more confortable


non pressure solar water heater working principle

3. Copper heat pipe vacuum tubes VS Regular solar tubes

There are copper heat pipe inside each vacuum tubes, work as heat exchanger, thus, there is NO water inside each vacuum tubes,
even if one of the vacuum tube broke down, the whole hot water heating system will keep on working perfect,
Compared with high pressure, non pressure solar water heater, due to there is water running inside each solar vacuum tubes, if one vacuum tube beak down, all the water will leak out, system will not work.


4. Anti-freezing performance or not?

Due to copper heat pipe with superior anti-freezing performance,
it can well work under – 35~ -40 degree ambient, thus, no need to worry about frozen problem in winter,
while, for non pressuresolarwater heater, due to water will fill inside each vacuum tubes, when temperature is lower than – 5 degree, tube will have great risk of burst due tofrozen.

compact pressurized solar water heater working principles

5. Energy loss Higher  or Lower?

Compact heat pipe is closed loop system, with less energy loss, and copper heat pipe with high efficiency, thus, compact highpressure is more efficiency than non pressure solar water heater


6. Cost Comparison

Due to inner tank of high pressure system is much thicker and each vacuum tubes are well configured with copper heat pipe,which make the construction of of high pressure solar water heater more expensive,
compared with high pressure solar water heater, non pressure solar system is affordable, with shorter RIO period.


In a nutshell,

world widely, non pressure is the best selling model in the market, due to it is simple & easy for maintenance,cost effective in price, it enjoy a great market globally,
while, for region with good purchasing power and harsh & long winter region, high pressure solar system will be the premium choice.

Which one do you prefer to?



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