Raypak rp2100 blew out it's unitherm governor last night

[Dagobah]

We had our first freeze in Dallas last night. Woke up this morning to water pouring out of the unitherm governor port on the rp2100 while the system was cycling for freeze guard. I found the plug and the thermostat (which looks super rusted and gunked up) on the ground. Turned everything off and went into work.

Some questions:

• Why did the UG blow out? (Freeze guard was on, and I had the pool running all night.)
• Is the fix simple as replacing the UG and the cap?

Other info:
I haven't used this heater in a couple years. It worked when we moved into the house, but a year later stopped heating. Just never got around to having it fixed. When turned on, you can hear the ignition firing and smell gas, but never seems to light. Are these problems related?

Thanks!

 

[ps0303]

Wow a freeze already in TX. Yes replace both parts. Why did it happen? Well water couldn't flow correctly because of the gunked up unitherm.

 

[Dagobah]

Update: I had my pool guy come out. The thermostat seized up, causing pressure to build up and it to blow out.

Worse news is that my heater is shot. Not from this, but the bottom fins are all rusted out. Went ahead and just bypassed the heater to get it running. The threads were stripped, so we couldn't just cap it.

Total to replace and install the heater would be $2400. I can live without a spa in the winter for that much.

 

[ps0303]

Is that price for another Raypak/Rheem?

 

[Dagobah]

Yea, he gave me two prices for a new Raypak/Rheem unit:

$2,800 new and installed: 399 BTU natural gas, elec ignition (what I have now)
$2,400 new and installed: 260 BTU natural gas, elec ignition

I would probably go with the 260 btu since we've only ever used it to heat our spa. Either way, won't be doing this for a while. Too many other priorities.