Gasifiers who heat their hot water...

[GS7]

As someone new to gasification systems I've always wondered if you're heating your hot water in addition to heating your home, does it matter from an efficiency standpoint which heat exchanger you plumb to first? The heat exchanger for your home, or the heat exchanger for your hot water?

 

[flyingcow]

FWIW- I have unpressurized storage. The DHW coil is separate from the HX that heats the storage tank. The DHW is just hanging in the tank, not connected directly to the boiler.

 

[ewdudley]

Doesn't matter for efficiency. Virtually all systems give DHW first dibs. [Edit: That is to say all systems that have to make a choice.]

 

[Eric Johnson]

I just plumbed the domestic hot water hx to be first in like. It just seemed to make the most sense.

 

[woodsmaster]

Hot water first for fast recovery. it should still be plenty warm to heat the house

 

[maple1]

One doesn't have to be first - does it?

Mine is zoned same as my heating zones, so whichever one needs it gets it.

 

[redmaple172]

Another option if you needed a new DHW tank is an indirect water heater. Piped as a zone off your heat system. I just priced 50 gal for a job, about $1,000. That would mean using boiler in summer for DHW too.

 

[KenLockett]

One doesn't have to be first - does it?

Mine is zoned same as my heating zones, so whichever one needs it gets it.

My DHW zone and two heating zones are plumbed off the common header although from a 'first path' point of view my DHW is first branch plumbed. What I have noticed is that the DHW will effectively 'starve' the heating zones until the DHW recovers. When I say starved, the there is some heating out to zones but majority to the DHW loop. This is easily observed with infrared thermometer/gun. Normally not an issue unless extremely cold and family members taking multiple showers that coincide with the early morning recovery (based upon thermostat schedule) of the main downstairs heating zone. Just takes longer to recover temperature downstairs after cold night. Just assumed this was based upon design standard so DHW has priority for fast recovery.

 

[Whitepine2]

Another option if you needed a new DHW tank is an indirect water heater. Piped as a zone off your heat system. I just priced 50 gal for a job, about $1,000. That would mean using boiler in summer for DHW too.

This is what I do I have an 80 gal. water store only need to run oil every 3 or 4 days depending on usage works for me.

 

[GS7]

As someone new to gasification systems I've always wondered if you're heating your hot water in addition to heating your home, does it matter from an efficiency standpoint which heat exchanger you plumb to first? The heat exchanger for your home, or the heat exchanger for your hot water?

As someone new to gasification systems I've always wondered if you're heating your hot water in addition to heating your home, does it matter from an efficiency standpoint which heat exchanger you plumb to first? The heat exchanger for your home, or the heat exchanger for your hot water?

Thanks for all the feedback. What prompted this question was after having gotten through this installation and being no expert I wonder could my set up be improved upon? So here's my set up. What does it mean when some of you plumb in parallel and what are the benefits? I guess I'm at the stage of what happens if I were to do this or that. The only things I've really added were a bypass valve so hot water won't compete with AC in the summer, a Caleffi air separator, and a Caleffi Dirtmag dirt separator. Does anyone see potential for improvement. In the off season I can make adjustments. Again, thanks for all the feedback.

 

[GS7]

Doesn't matter for efficiency. Virtually all systems give DHW first dibs. [Edit: That is to say all systems that have to make a choice.]

Thanks for pointing that out, I had no idea what was most often done or if there was an impact one way or the other.