Yet another A2W conversion of split AC

ZorBoz · 04-22-22, 06:37 AM

Hi to all.
I am trying to make A2W conversion of split AC from Toshiba RAV-SM563AT-E outdoor unit. Its power is around 18000 Btu's or 5,3-6kW.
I live in low energy consumption house that uses around 10000 kWh of energy for year round heating cooking and hot water, and it uses condensing gas boiler with support of one solar panel for DHW.
My boiler is Aurocompact from Vaillant. It has 150l tank for DHW. My problem is that system can't really cope with low power since boiler modulates its power from 19kW to around 4 kW. So i would use A2W system for purpose of supplementing my heating when its not so cold and COP should be high.
Its around 5 degrees Celsius and below where i would kick in the gas boiler.
My questions are:
1. Do I need any kind of buffer in water system, or I can drive my house directly from BPHE. My system is compromised of oversized radiators, and supplemental underfloor heating in one circuit. (RTL valves for underfloor)
2. What would be the size of BPHE for my AC and where to source it (Aliexpress or something else.) I assume that flare connectors on gas side would be a good thing since AC has 1/2 and 1/4 inch connector.
3. Does anybody knows a good pump for this applications. I was thinking of Willo Yonos Pico or something that has variable speed to play with best heat trasnfer from BPHE.

Ty all for any kind of information.

04-22-22, 06:37 AM	#1
ZorBoz Lurking Renovator Join Date: Apr 2022 Location: Croatia Posts: 2 Thanks: 0 Thanked 0 Times in 0 Posts	Yet another A2W conversion of split AC Hi to all. I am trying to make A2W conversion of split AC from Toshiba RAV-SM563AT-E outdoor unit. Its power is around 18000 Btu's or 5,3-6kW. I live in low energy consumption house that uses around 10000 kWh of energy for year round heating cooking and hot water, and it uses condensing gas boiler with support of one solar panel for DHW. My boiler is Aurocompact from Vaillant. It has 150l tank for DHW. My problem is that system can't really cope with low power since boiler modulates its power from 19kW to around 4 kW. So i would use A2W system for purpose of supplementing my heating when its not so cold and COP should be high. Its around 5 degrees Celsius and below where i would kick in the gas boiler. My questions are: 1. Do I need any kind of buffer in water system, or I can drive my house directly from BPHE. My system is compromised of oversized radiators, and supplemental underfloor heating in one circuit. (RTL valves for underfloor) 2. What would be the size of BPHE for my AC and where to source it (Aliexpress or something else.) I assume that flare connectors on gas side would be a good thing since AC has 1/2 and 1/4 inch connector. 3. Does anybody knows a good pump for this applications. I was thinking of Willo Yonos Pico or something that has variable speed to play with best heat trasnfer from BPHE. Ty all for any kind of information.