What happens if aquastat malfunctions

General Outdoor Boiler Discussion
Post Reply
Posts: 34
Joined: Mon Jun 12, 2017 7:17 pm
OWB brand: Johnson
OWB Model: Little John
Location: A bit north of Milwaukee WI

What happens if aquastat malfunctions

Post by larryjbjr » Fri Jul 14, 2017 2:46 pm

Just was thinking, on my Johnson little John, what would happen if the aquastat malfunctioned and never shut the fire down? I'm imagining something just shy of a Thermo nuclear meltdown. Am I overreacting?

Do people normally have something on the boiler to shut everything down someway or somehow dump heat if it gets too hot?

I was just thinking today that the aquastat is like 18 years old. Should I be concerned and replace it maybe?

Last edited by larryjbjr on Fri Jul 14, 2017 2:46 pm, edited 1 time in total.

Posts: 57
Joined: Sat Oct 29, 2016 9:18 pm
OWB brand: Central Boiler
OWB Model: 4436
Location: Southern Indiana

Re: What happens if aquastat malfunctions

Post by Bull » Sun Jul 16, 2017 7:15 pm

It depends on which way it malfunctions, one way your fire goes out and the other way it looks like a steam locomotive is in your yard. I think some aquastats have a second higher temp shut down built in.

User avatar
Posts: 321
Joined: Mon Jun 23, 2014 6:25 pm
OWB brand: Woodmaster
OWB Model: 4400
Location: Clayton, Mi

Re: What happens if aquastat malfunctions

Post by Yotehunter66 » Thu Aug 10, 2017 5:05 pm

Besides the normal temp setting, mine has a high and low setting.
Plants need to breath too, CO2!
Troybilt Logsplitter
Husqvarna 372 xp
Poulan 2300
Makita 520s
McCulloch Eager Beaver 2.3
Ford 8N
Simplicity 9518

Posts: 2
Joined: Wed Nov 08, 2017 5:31 am
OWB brand: Heatmaster
OWB Model: G200s

Re: What happens if aquastat malfunctions

Post by Northwind » Thu Nov 09, 2017 8:08 am

You also have a High Limit aquastat , its located behind the insulation top left back of unit , mine is set to 195. Follow the bx wiring to find it.

Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests