Compatible system b...
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Compatible system boilers with glycol/anti-freeze

3 Posts
3 Users
Estimable Member
274 kWhs
Joined: 12 months ago
Posts: 51
Topic starter  

Hi all and Happy New Year!

Question for any techies. Which system boilers would be compatible to use with a ASHP hybrid system containing glycol (anti-freeze)?

Thanks in advance.


Eminent Member
95 kWhs
Joined: 11 months ago
Posts: 8

There are quite a few that can, I know all the ones designed to sit outside can.


We have our boiler as backup to the 2 ASHP but it has a separate loop to the buffer so no need for glycol in that run. 

Derek M reacted
Illustrious Member Admin
9770 kWhs
Joined: 3 years ago
Posts: 1757

Most boiler manufacturers will advise on glycol levels acceptable within their boilers, so the best course of action would probably be to select a couple of manufacturers and see what they say. Some may insist on mechanical separation and some may be fine with it all mixing together. Get there advice so that you don’t jeopardize warranties.

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