From e202f172f833af2533e69c1b2d09bc5fdbd80103 Mon Sep 17 00:00:00 2001 From: openhp <60161126+openhp@users.noreply.github.com> Date: Sun, 28 Mar 2021 22:43:22 +0000 Subject: [PATCH] Update README.md --- README.md | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/README.md b/README.md index 19f970e..08aedcd 100644 --- a/README.md +++ b/README.md @@ -127,24 +127,25 @@ One day I've realized that a netbook with a serial console is a good diagnostic If you want a compact and visual tool - this device is for you, so check [the Service Display Page](https://github.com/openhp/ServiceDisplay/) .

## Starting up the heat pump system for the first time and charging refrigerant -This is an easy part, but if you don't have experience it will take time.
-You have performed a pressure test and vacuuming. It's time to charge your system. +This is an easy part, but if you don't have experience it will take time.
+You have performed a pressure test and vacuuming. It's time to charge your system.
Let's say you don't know how to calculate the amount of refrigerant in a recently built system, so follow next steps: - charge a small amount (for example 300 g) of refrigerant, - get ready for a system protective stops by Tae or Tbe temperature, this is a normal system behavior while refilling refrigerant, - power on your heat pump, -- after compressor startup suction temperature will be about -20 ...- 40 ° C (according to the suction pressure on the pressure gauge), +- after compressor startup suction temperature will be about -20 ...- 40 °C (according to the suction pressure on the pressure gauge), - for single-component refrigerants: slightly open the valve of the HVAC gauge manifold and start adding refrigerant through the gas phase on the cold side, -- for multi-component refrigerants: turn over the refrigerant cylinder, VERY SLIGHTLY open the HVAC manifold valve and start adding a VERY LITTLE amounts through the liquid phase, -- continue, until the suction temperature (according to the suction pressure on the manometer) is ~ 10 ... 15 °C lower than the temperature of the heat source (example: the temperature at the inlet of the mixture of water and antifreeze from the closed ground loop is + 8 °C, so the suction temperature should be -2 ..- 7), +- for multi-component refrigerants: turn over the refrigerant cylinder, VERY SLIGHTLY open the HVAC manifold valve and start adding VERY LITTLE amounts through the liquid phase, +- continue, until the suction temperature (according to the suction pressure on the manometer) is ~ 10 ... 12 °C lower than the temperature of the heat source (example: the temperature at the inlet of the mixture of water and antifreeze from the closed ground loop is + 8 °C, so the suction temperature should be -2 ..- 4), - close the manifold valve, -- at every step check the discharge pressure: it should not be ba above the discharge sensor temperature (Tbc), -- wait for the system to heat the target to a almost stable temperature, add little amounts of refrigerant while temperature increases (and suction decreases), -- stop if you are sure that the heating process is now proceeding very slowly, -- take a final look and charge when the system is stable and the heat pump stops normally (setpoint is reached), this may take 12 hours or more, and now the target difference between the suction pressure temperature and the temperature from the T sensor should be 3 ... 6 °C. +- at every step check the discharge pressure: it should not be above the discharge sensor temperature (Tbc), +- wait for the system to heat the target to an almost stable temperature, add little amounts of refrigerant while temperature increases (and suction decreases), +- stop if you are sure that the heating process proceeding slowly, +- take a final look and charge when the system is stable and the heat pump stops normally (setpoint is reached), this may take 12 hours or more, +- after the final refilling difference between the suction pressure temperature and the Tae sensor temperature should be 3 ... 6 °C. This algo is good and safe both the first time and as a starting point. As you gain experience, you will get yours much easier and faster.
-Also use "manual EEV mode" during charging process.
+Also, use "manual EEV mode" during refilling process.

## Hints For more information about Heat Pumps look at [Wikipedia about HP](https://en.wikipedia.org/wiki/Heat_pump).