Pressure drop during call for pumps

Pressure drop during call for pumps

PostBy: Dave 1234 On: Tue Apr 08, 2014 7:50 am

Good morning,
I need some education about change of pressure during a call for heat. My buddys new system changes pressure every time the pumps start up. He checked his X-tank, its ok. and his system has two X-tanks.

Whats the deal ?

Dissclamer, Heating systems are only a novelty hobby for us. We are not pros. Nope !

Thanks !!!

Dave
Dave 1234
 
Stove/Furnace Make: EFM
Stove/Furnace Model: 520

Re: Pressure drop during call for pumps

PostBy: Carbon12 On: Tue Apr 08, 2014 8:58 am

Air in the systems???
Carbon12
 
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice/Anthracite
Other Heating: Heat Pump/Forced Hot Air Oil Furnace

Re: Pressure drop during call for pumps

PostBy: Rob R. On: Tue Apr 08, 2014 9:58 am

Where are the circulators, expansion tanks, and pressure gauges located in relation to each other?
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy


Re: Pressure drop during call for pumps

PostBy: Dave 1234 On: Tue Apr 08, 2014 11:15 am

Rob, Carbon 12.
The boiler is in an out building , a x-tank , circulator , air bleeder and pressure gague is at the boiler .Also all of the above in house at the oil burner too.

Dave
Dave 1234
 
Stove/Furnace Make: EFM
Stove/Furnace Model: 520

Re: Pressure drop during call for pumps

PostBy: Sting On: Tue Apr 08, 2014 12:30 pm

long read - but this question will need it...

http://www.heatinghelp.com/article/343/ ... ure-Change
Sting
 
Other Heating: BurnHAM=NG-gas

Re: Pressure drop during call for pumps

PostBy: carlherrnstein On: Tue Apr 08, 2014 5:32 pm

I would imagine that its normal for the pressure to drop when the circulator pumps come on because liquid water expands when heated and contracts when cooled. The water in the boiler is hot and expanded(higher pressure) then the pumps come on and the boiler water starts to cool off and contract(lower pressure)

However I'm not a hydronic guy an this is only a hypothesis.
carlherrnstein
 
Hot Air Coal Stoker Stove: combustioneer model 77B
Coal Size/Type: pea stoker/Ohio bituminous

Re: Pressure drop during call for pumps

PostBy: Sting On: Tue Apr 08, 2014 6:05 pm

carlherrnstein wrote:I would imagine that its normal for the pressure to drop when the circulator pumps come on because liquid water expands when heated and contracts when cooled. The water in the boiler is hot and expanded(higher pressure) then the pumps come on and the boiler water starts to cool off and contract(lower pressure)

However I'm not a hydronic guy an this is only a hypothesis.


Please read the link I provided - it directly address's this
Sting
 
Other Heating: BurnHAM=NG-gas

Re: Pressure drop during call for pumps

PostBy: carlherrnstein On: Tue Apr 08, 2014 6:25 pm

Very interesting.
carlherrnstein
 
Hot Air Coal Stoker Stove: combustioneer model 77B
Coal Size/Type: pea stoker/Ohio bituminous

Re: Pressure drop during call for pumps

PostBy: Dave 1234 On: Tue Apr 08, 2014 6:47 pm

Sting,
You find a way to simplify heating that I can grasp. I read it and do see why you pointed to this article.
Makes sense !
Thank-you ........Again

Dave
Sting wrote:long read - but this question will need it...

http://www.heatinghelp.com/article/343/ ... ure-Change
Dave 1234
 
Stove/Furnace Make: EFM
Stove/Furnace Model: 520

Re: Pressure drop during call for pumps

PostBy: Sting On: Tue Apr 08, 2014 7:41 pm

good deal
Sting
 
Other Heating: BurnHAM=NG-gas