Yet another heater bypass question..

[Mark McLeroy]

Hi All:
Thanks to the help from many of you in this forum, the upgrades to my system are almost complete. One of those upgrades was an automated heater bypass. One of the things I learned was that it wasn't a good idea to do a complete bypass of the heater when not using the heater. So using an Intellivalve in conjunction with a Intelliflo pump I have it set to push 42GPM through the heat pump heater when calling for heat (that's 2200 RPMS and sending the full flow of water through the heater). When not calling for heat AND during my low RPM times I have it set on partial bypass and 1200 RPMs. This gives me 30 GPM total through the system and 10 GPM though the heater. Would 10 GPM be enough for the "cool down" after the heater shuts down?

Thanks.
Mark McLeroy

 

[ajw22]

A heat pump heater does not need the cool down period that a gas heater does.

 

[blazer58]

Why did they say not to do a full bypass of a heater ?

 

[ajw22]

Why did they say not to do a full bypass of a heater ?

You don't want stagnant water sitting in the heater.

On addition heaters have pressure switches and you can lock in water pressure that will allow the heater to run without water flowing through it.

Both reasons make it better to let a small flow of water through the heater when bypassed.