Aqua Hot

[doug a]

good afternoon folks im having problums with aquahot wont restart after it cools down 99 monaco sig series aqua hot model 431/12volt i cant seem to find the pack of 4 thermostates any help would be appreciated

[Mike Canter]

Hi Doug, welcome to the forum. When you say it will not restart do you mean the boiler will not ignite? If so then can you hear the pump and blower running initially for three minutes then shutting down?

[doug a]

hi mike what happend was one day nothing would start with aqua hot so i took it a part and cleaned every thing i could find put all back together worked fine for 4 months quit again wont even try any more no fan to start or any thing else sorry i forgot it fired once ---worked perfectly to shut off temp and now wont restart when it cooled down

[Mike Canter]

By any chance did you disconnect any batteries or run them down?

[Dr4Film]

I have the same model as yours.

Does the light in the AH Diesel switch remain on and lit when the burner will not fire up?

What happens when you recycle the switch off and back on?

I highly recommend joining Roger Berke's Hydronic Heating forum. He is a wealth of knowledge and will help you solve your problem. It's free for the non-Premium members forum.

Forum Rv Hydronic Heater Repair - Welcome

I have attached the PDF which shows the Thermostats.

It is a document used to troubleshoot the electric portion of the Aqua-Hot but it shows where the thermostats are located plus a close-up of all four of them.

Dr4Film ----- Richard

[doug a]

thanks richard and mike i will open up again today isee where the thermostates are now ill shut power off untill i get in position to test thanks again. this winter we are in duncan bc canada ,so it's not to cold the electric is keeping water usable , and we are using electric heaters thanks again

[Mike Canter]

Doug, a real simple thing here and it has happened to me on several occasion is that if no burner fan or pump running and no red light on the burner power switch then use a toothpick and reset the low voltage breaker on the control panel in the basement. Hopefully it is something that simple

[Coma]

The 431/12 of that vintage resets on a cycle of the burner switch. There are fuses underneath the cover to check. There is a high temp limit sensor to check in addition to the operating temp sensor per the DR's info.

Mine would operate erratically, motor turn but no light. It turns out the exhaust had collapsed and was plugging exhaust. There are motor clutches to jam also, but you should work through the cheap fixes first.