EFM 520 Aquastat

EFM 520 Aquastat

PostBy: northernmainecoal On: Wed Jan 22, 2014 9:39 am

I finished the install of our new EFM520 yesterday. I have programmed the aquastat at the following:
High limit- 195
Low limit- 177
Low limit differential- 12
The boiler is coming on at 195 and shutting off at 185, any idea why this would be? Am I programming it incorrectly? Is it possible there is an issue with the aquastat itself?
Thanks
Rob
northernmainecoal
 
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Hitzer 30-95
Baseburners & Antiques: Herald Baseheater #6
Coal Size/Type: Rice/Nut/Stove

Re: EFM 520 Aquastat

PostBy: GoodProphets On: Wed Jan 22, 2014 2:56 pm

Are you taking those readings posted from the aquastat or the gauge from the boiler?

Sounds like wiring is not correct.

I am not a wiring genius, so hold tight until pros come to help out.

Fill in your profile with location, etc, it could help in the future
GoodProphets
 
Stoker Coal Boiler: EFM DF520
Coal Size/Type: Anthra Rice
Other Heating: 3 Fireplaces

Re: EFM 520 Aquastat

PostBy: franpipeman On: Wed Jan 22, 2014 3:06 pm

there are many different types of aqua stats what is the manufacture and model number?
franpipeman
 
Stoker Coal Boiler: efm 520 stoker fitzgibbons pressure vessel
Hand Fed Coal Stove: harman, russo
Coal Size/Type: rice

Re: EFM 520 Aquastat

PostBy: northernmainecoal On: Wed Jan 22, 2014 3:08 pm

My plumber just called with what he hopes is the answer. The 520 is piped in with my existing oil boiler because of this we are constantly circulating water between the two boilers. In order to do that the TT has to be jumped on the aquastat which is also the reason it is acting funny (that's my understanding of what he had to say at least) Without looking at the aquastat I believe is an L7224A, but I'll double check when I get home
Image
northernmainecoal
 
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Hitzer 30-95
Baseburners & Antiques: Herald Baseheater #6
Coal Size/Type: Rice/Nut/Stove

Re: EFM 520 Aquastat

PostBy: stoker-man On: Wed Jan 22, 2014 4:19 pm

You should move the high and low limit settings apart by 40 degrees or you may have trouble with your fire going out. 20 degrees doesn't work with coal when the temperature is more moderate.
stoker-man
 
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove

Re: EFM 520 Aquastat

PostBy: Rob R. On: Wed Jan 22, 2014 5:57 pm

If you short the TT terminals the aquastat will try to keep the boiler temperature at the high limit setting...which is what you are observing. At 195 it will shut down the stoker, when it gets to 185 (high limit differential is fixed at 10 degrees) the stoker will resume operation.

The way your plumber has it setup will work, but I prefer to connect the TT terminals to the end switch of the zone relay(s).
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

Re: EFM 520 Aquastat

PostBy: McGiever On: Wed Jan 22, 2014 6:02 pm

Is it a typo? He says On @ 195...and Off @185 ???
McGiever
 
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hot Air Coal Stoker Stove: HARMAN MAGNUM
Hand Fed Coal Stove: RADIANT HOME AIR BLAST
Baseburners & Antiques: OUR GLENWOOD 111 BASEBURNER "1908"
Coal Size/Type: PEA / ANTHRACITE, NUT-STOVE / ANTHRACITE
Other Heating: Ground Source Heat Pump
Stove/Furnace Make: Hydro Heat /Mega Tek

Re: EFM 520 Aquastat

PostBy: Rob R. On: Wed Jan 22, 2014 6:11 pm

McGiever wrote:Is it a typo? He says On @ 195...and Off @185 ???


I assumed it was a typo. if not, I have no explanation.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

Re: EFM 520 Aquastat

PostBy: northernmainecoal On: Thu Jan 23, 2014 2:17 pm

Yes it was a typo, sorry
To fix the issue we removed C1 and C2 connections and put them on L1 and L2 so if the boiler has power the circ will run. removed the jump from the TT terminals and all is well
thank you
northernmainecoal
 
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Hitzer 30-95
Baseburners & Antiques: Herald Baseheater #6
Coal Size/Type: Rice/Nut/Stove

Re: EFM 520 Aquastat

PostBy: Rob R. On: Fri Jan 24, 2014 5:34 pm

That is fine...as long as the heating load doesn't drag the boiler down to a temperature less than desired.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

Re: EFM 520 Aquastat

PostBy: northernmainecoal On: Fri Jan 24, 2014 5:53 pm

Its been working beautifully. The temps here have been 20-30 below with the wind chill this week. Even with constant call from the t stats its been maintaining the LL seemingly effortlessly. I'm considering dropping from 4 teeth to 3
northernmainecoal
 
Stoker Coal Boiler: EFM 520
Hand Fed Coal Stove: Hitzer 30-95
Baseburners & Antiques: Herald Baseheater #6
Coal Size/Type: Rice/Nut/Stove