No power

[Tinstar]

My 2002 Monaco Windsor is parked at home in 0 degree weather. I turned the heat pump on 40 degrees to keep it thawed. I just went out to check and I found no power. I've got 50 amps going to the m/h and it's working. I opened my panel and the breakers are on (yes, I checked by throwing them off then back on). I've got a Xantrex RS2000 Sine Wave Inverter/Charger and when looking at the control panel it showed a FAULT --- "Contacts Welded". What does that mean and how do I fix it? Does that have anything to do with the heat pumps?

I know a heat pump doesn't work very well below a certain temperature but I wouldn't think it would cause them to not have any power at all.
I do have power at the thermostat and am able to cycle through the settings. OH, I nearly forgot, the batteries are at 13.2 volts and some outlets running from the inverter are powered with 120 volts so it's not a low battery issue.

Thanks for any help.

[dougrainer]

Bay Heater Instructions. This heater may have a Temp switch located ON the Heater, instead of the hidden behind the water Bay panel auto Tstat. Doug

The heater is controlled using two switches, one on the heater itself and a
remote “SYSTEMS HEAT’ switch located in an inside overhead compartment
next to entrance door. Both switches must be in ON position for the heater to
operate. Either switch in the OFF position will turn the heater off.

[rgatijnet1]

Welded contacts is sometimes the result of rapid cycling of the electrical contactor. The 15 power outages certainly could have contributed to this situation. Contact damage can also occur with voltage that has gotten too low to properly hold the two contacts tight.

[dougrainer]

Tinstar wrote:

dougrainer wrote:

PastorCharlie wrote:
Why would a 2,000 watt inverter be wired into a heat pump circuit?

Its not. He just has 2 problems. Doug

Doug, That's what I was wondering. I couldn't imagine them being fed from the inverter but I didn't know. Does the a/c/heat-pump wire straight into the 120-volt circuit panel and it is not controlled by the inverter. I don't have aqua-hot. I have ran extension cords and am using small space heaters to keep water from freezing.

Sunday morning, I had about 15 power outages that were only out for about 3 to 5 seconds which may have caused the problems. Have you ever seen "welded contacts" as a fault?

NO Aqua Hot? VERY unusual. I cannot remember when any of the hi line Monacos from 20 years ago did NOT have the optional Aqua hot. So same scenario, when the Ambient temp drops below 36/38 degrees the furnaces will automatically start and run, as long as the LP is turned ON. Your model should also have the 12 volt water bay heater that is turned on by a tstat switch mounted in the water bay inner wall, when the temp in the bay goes below 34 degrees. BUT, you MUST have that Heater switch turned ON. the switch is on the inside by the monitor panel display board. Now, to your question. NO OEM will ever run a roof AC or HP thru the Inverter/charger. Monaco did not. So, any loss of 120 power to the roof HP's is not caused by the Inverter/Charger. You DO have a Intellitec Energy Management System(EMS) that the roof HP's 120 power does go thru. THIS system can kill 120 power to the roof HP's if it is malfunctioning, but the Inverter will not cause such a problem. Your EMS wall display will show the status of the Power to the roof HP's. Doug

[Tinstar]

dougrainer wrote:

PastorCharlie wrote:
Why would a 2,000 watt inverter be wired into a heat pump circuit?

Its not. He just has 2 problems. Doug

Doug, That's what I was wondering. I couldn't imagine them being fed from the inverter but I didn't know. Does the a/c/heat-pump wire straight into the 120-volt circuit panel and it is not controlled by the inverter. I don't have aqua-hot. I have ran extension cords and am using small space heaters to keep water from freezing.

Sunday morning, I had about 15 power outages that were only out for about 3 to 5 seconds which may have caused the problems. Have you ever seen "welded contacts" as a fault?

[pianotuna]

At 25 f (-3.88c) heat pumps become less efficient than resistance heating.

They work well down to 40 f (10 c)

[naturist]

CA Traveler wrote:
Heat pumps don't work at 0F and I would not leave them on at 0F. In fact I have 2 dedicated 20A circuits for ceramic heaters. The water area includes both a DC heater and AquaHot register. This leaves the fresh water tank which is only protected by the AquaHot.

Therefore in really cold weather I'd use the electric heaters and Aquahot or winterize.

X2. Heat pumps are more or less useless below freezing, and actually lose function starting around 40 degrees F.

[dougrainer]

You did not state IF you have the Aqua Hot system activated and ON. Heat Pumps are completely separate from the furnace/water heater system(Aqua Hot). IF you did not have the Aqua Hot activated and you are NOT inside storage, you may have a burst Aqua Hot reservoir if the Propylene is not at the correct antifreeze concentration. On your HP system, IF the Aqua Hot was activated, then the Aqua Hot furnace system would have come on once the ambient temp dropped below 36/38 degrees. Doug

[dougrainer]

PastorCharlie wrote:
Why would a 2,000 watt inverter be wired into a heat pump circuit?

Its not. He just has 2 problems. Doug

[PastorCharlie]

Why would a 2,000 watt inverter be wired into a heat pump circuit?

[down_home]

...........

[pianotuna]

Sounds like the internal transfer switch is "stuck". By pass the inverter/charger. Add a battery charger to the "house" bank.

If out of warranty, fix it, sell it, and buy a Victron inverter/charger.

[MURPHY55347]

Last fall we got into some weather that was about 20 degrees while using the heat pumps. Got up at 3:00am to the smell of electrical smoke but everything was still running. Did not expect it to run at that temp. Upon investigating in the morning found the transfer switch had fried. Guessing the heat pump was pulling a bunch of current and the contacts may have been loose. Loose contacts is a known problem and should be checked every year. I went out and bought an inch pound screwdriver just for that reason.

[CA_Traveler]

Heat pumps don't work at 0F and I would not leave them on at 0F. In fact I have 2 dedicated 20A circuits for ceramic heaters. The water area includes both a DC heater and AquaHot register. This leaves the fresh water tank which is only protected by the AquaHot.

Therefore in really cold weather I'd use the electric heaters and Aquahot or winterize.

[CA_Traveler]

The manual shows an external TS for shore/gen, then the charger/inverter then the CB panel. This suggests that any charger/inverter internal TS contact problem could effect all AC power including the heat pumps.

A number of different problems with the heat pumps or elsewhere could cause a contact issue. A power outage problem cause contact arcing as the power goes off and on. Including the inverter switching on/off to supply AC power to the panel.

While my chager/inverter is not a whole house type unit I never leave the inverter on which allows automatic AC switching. I also turn off all loads before connecting/disconnecting AC shore power. Both of these significantly reduce relay contact arcing.