Skip to main content ↑ ↓
Topic: How do you reset the low coolant fault on a hydro-hot? (Read 795 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

How do you reset the low coolant fault on a hydro-hot?

Yahoo Message Number: 67780
A couple of days ago we had no heat or hot water. The switches were lit inside, so I checked the bay and the low cooalnt light was lit.
The overflow tank was above the cold mark and the tank was cold so I removed the radiator cap and sure enough the coolant was well below the neck. I added coolant to bring it all the way up and out the cap back on but the low coolant stayed lit and I couldn't get the hydro-hot to fire up.
The next daay -- after a long drive -- the low cooloant light was out and the Hydro-Hot was working as it should. The overflow tank also showed more coolant (since the unit was now heating).
Since that episode we've travelled about 800 miles and everything is still fine.
So, how do you reset the low-coolant fault and/or ideas as to why the overflow tank wouldn't have been low if the main unit was low?
 

Re: How do you reset the low coolant fault on a hydro-hot?

Reply #1 –
Yahoo Message Number: 67783
I don't believe that there is any reset for the low water cutoff. There is a level sensor inside the tank that makes a connection when the fluid level drops below a certain level. When you added coolant the sensor may have been stuck and driving freed it up. Just a guess.
The reason that the fluid may be ok in the overflow but down in the main tank is at some point the level was low enough in the main tank to develop an air pocket up in the neck. When that air pocket is big enough it prevents the vacuum from forming to draw the coolant back into the tank as it cools.
There can be many reasons for coolant loss such as minor leaks and evaporation. The most common place to check is the overflow tube particularly where it joins the neck at the radiator cap. It often cracks or splits right there and you can cut of a small portion and put it back .. The other place is the radiator cap itself. It should be replaced periodically and it are a standard 13 lb automotive cap available at most Auto Parts stores.
It is a good idea to check the level in the overflow tank periodically to see if it is raising and dropping with the cooling and heating of the unit. If you find that it is not then you have no idea of the level of the coolant in the tank. When that happens remove the radiator cap after letting the unit cool down and check the coolant level. It should be full right to the top.

Don Seager

2004 Allure 31046