Where to find an internal thermostat for our Galaxy Slant/Fin boiler

KarenO

Hi there! We are in deparate need of an internal thermostat for our Slant Fin boiler. Its quite old, but we can't afford a new boiler at the moment. I have contacted Parts 4 Heating to see if they have the part, but thought I would reach out here as well. Any recommendations would be GREATLY appreciated. Happy Holidays!

bburd

You probably mean "aquastat". They are usually industry standard components for older boilers, and readily available. Look for a gray box with wiring going in and out of it threaded into the boiler body itself, not the oil/gas burner.

How do you know you need one?

Can you show us a picture of what you have? 

KarenO

Thanks for your response! We were told my our HVAC guys. They tried to source the part last time they were here, and ended up hardwiring it, and circumventing the "aquastat" (what they referred to as the internal thermostat. I DO see a grey box on the exterior of the boiler with wiring threading into the boiler.

Steamhead

Looks like that may be a roll-out safety. It is extremely dangerous to disable it.

@KarenO , where are you located? You need a real pro, and we might know someone............

KarenO

We are in Toronto, Ontario

KarenO

I just need to source the part (either aquastat or internal thermostat) We have HVAC company to install it.

Steamhead

Unfortunately, the site's contractor page doesn't go above the US-Canada border. Anyone know someone up that way?

KarenO

here is a better picture

Steamhead

Can you get close enough so we can see the writing on it? I've never seen that on a Slant/Fin.......

EBEBRATT-Ed

I am sure Slant Fin did not make that part. Someone else did.

KarenO

ok, thanks for the feedback! Really appreciate it.

EBEBRATT-Ed

I looked at a bunch of galaxy parts lists online. The only safety's listed are a blocked flue switch and a roll out switch but they were not mounted where that part is.

If you could get a close-up picture of that control so we could see the writing and the numbers that would help or just write down and post what you can read that might get the ball rolling.

gyrfalcon

I’ll chime in, for what it’s worth. I have an old slant fin galaxy.  The front cover can be slid up and off of the boiler , exposing the aqua stat , gas valve and burner tubes.  I’ll post pics as an example for the OP to use as a reference.  

gyrfalcon

The aquastat on my boiler is L8148E 1190.  Again just for reference. @KarenO may have a different brand or version of the Honeywell. As soon as you can share some more  pictures or specifications of your boiler, the nice folks here should have an expedient and accurate answer for you. 

mattmia2

what part do you need? that part mounted to the bottom of the junction box looks like a control transformer that is potted.

gyrfalcon

Also, this is on a strictly steam thread.  This is a forced hot water boiler, no? 

Steamhead

gyrfalcon said:

Also, this is on a strictly steam thread.  This is a forced hot water boiler, no? 

@Erin Holohan Haskell ?

Erin Holohan Haskell

Steamhead said:

gyrfalcon said:

Also, this is on a strictly steam thread.  This is a forced hot water boiler, no? 

@Erin Holohan Haskell ?

You got it. Thanks!

HomerJSmith

The red arrow points to the aquastat. The aquastat controls the boiler water temperature and turns on the boiler pump. The wall thermostat turns on the aquastat's relay. That relay turns on the boiler and the boiler pump. Inside the cover of that gray box is a label that tell you what the model # of that aquastat is. Post that model #. That is what you're calling an internal thermostat. The greatest failure of these aquastats is that the opening and closing of the relay breaks the relays foil connection to the circuit board which fails to operate or the operation is intermittent. It is all caused by a solder break on the circuit board where the relay connect to it.

SaintNow

the boiler pictured is the closest I've found to my GG125 Slant Fin. I'm sure the aqua stat is bad exactly as described by HomerJSmith,

"the opening and closing of the relay breaks the relays foil connection to the circuit board which fails to operate or the operation is intermittent. It is all caused by a solder break on the circuit board where the relay connect to it."

Playing around with it I can tell this is exactly the problem, I can see sparks on the back of the relay where the connections are worn.

https://www.homedepot.com/p/Aqua-stat-Relay-L8148E1265/203193175#overlay

My question is can I use this aquastat from Home Depot to replace my old one…..and also, it requires 24 volt thermostat set at 0.2A heat anticipator …..I'm pretty sure my thermostat is 24 volt, not sure about heat anticipator setting, all was working fine before the relay wore out

Steamhead

@SaintNow , is your aquastat relay also an L8148E?

SaintNow

It's L8124E, finally got it figured out, thank you for all the help and great comments here……was looking around for a couple hours for answers and found the best here. I'm pretty sure now that my thermostat heat anticipator is set correctly as all was working fine for a long time before and I found the correct model number aquastat.

Thanks again.

SaintNow

couldn't find the model number anywhere on my aquastat, finally saw it specified in the wiring diagram.

HomerJSmith

Is this post still active? Don't worry about the anticipator setting. It mostly for forced air and not boilers. A lot of techs just set it to 0 for boilers.