ICE storm but no heat pump

[Moira]

I thought i was gonna be cool. I thought I was gonna be a contender but nooo.

So i am down here in the south, its been icing for several days. Finally we lost power sometime this morning.

So i fired up the generator, waited 30 minutes and then turned on a heat pump. So it has been blowing not freezing air for sometime and finally got the coach above freezing. Suddenly the blower stops but i can hear the heat pump is on. The no. 2 did it and the no. 3 did it. Not all at the same time of course. After waiting a few minutes i restart the heat pump and it blows again albeit colder air.

So i tried the aquahot. The coach is winterized but not the aquahot. The book says you can use it for heat even if you have winterized the hot water system. But after running it for 30 minutes im not getting any warm air from the furnace. Whats going on?
Sitting in my car. Thank you moira

[pasdad1]

Heat pumps aren’t going to work with outside temperature below about 40F….just not enough heat in the outside air for them to transfer to the outside.

Did you turn on the aquahot diesel burner? If it’s firing it would start producing heat within 5-10 minutes.

Can you confirm hot exhaust coming out the aquahot pipe?

Any fault lights on ?


If you can get to a Walmart or hardware store, you can buy a portable electric heater and run this on generator or shore power until you get this figured out.

[Jim_HiTek]

In case it's safe to drive, Walmart has several floor heaters that should keep you warm for around $12 each. Forced air. Set them on low and scatter them around the RV. I have 3 and generally use 2 in conjunction to a tower heater I found at a thrift store for $5. I run that one on high most of the time in the living room.

I've lived quite comfortably (suffering with drafts of cold occasionally) down to the 20's F with the heaters running.

But I have a 50 amp RV too and that's important. A 30 amp supply can't handle a bunch of floor heaters.

[Rob_M]

Originally Posted by pasdad1

If you can get to a Walmart or hardware store, you can buy a portable electric heater and run this on generator or shore power until you get this figured out.

Good luck finding a portable heater for sale anywhere after an ice storm in the South.

We had ice yesterday and lost power for 3 hours. About the time I got the coach warm and toasty, and we were about to go out there, the power came back on.

OP I wish I could help somehow but I’ve never operated an aqua hot.

[00 Buckshot]

Don't know what temperature you are trying to operate in but even if it is over 40 degrees a heat pump goes into a defrost cycle every so often depending on the outside temp. The fan shuts off and the compressor keeps on running. It reverses to generate heat outside to melt any ice building up on the coils. After this cycle it will reverse back and start blowing warm air again.

It sounds funny and will last a couple of minutes but this is normal with a HP.


My heat pumps work down to about 35 degrees but even when it is working perfectly it is blowing air less than your body temp so it feels cool .


Hope this makes sense.

[Moira]

Wow, i didnt know that about a heat pump, the fan shutting off and all. Thank you Buckshot. I know they are no good below 40 but thats what i have in the house, so i thought i would be able to heat this thing up slowly anyway.

I dont have any portable heaters but maybe a good thing to get for next time. They just scare me cause they are so unsafe.

Yes i have the diesel burner running. We are getting a little heat now in the bedroom. It took a very long time for it to come up but i did not put my hand in front of the exhaust.

My aquahot does not hVe fault lights that i know of. Just the light on the switch, which is on steady.

So ill tough it out i suppose. At least the heat pumps are operating normally. Thank you all.

[NLOVNIT]

Originally Posted by pasdad1

Heat pumps aren’t going to work with outside temperature below about 40F….just not enough heat in the outside air for them to transfer to the outside.

Did you turn on the aquahot diesel burner? If it’s firing it would start producing heat within 5-10 minutes.

Can you confirm hot exhaust coming out the aquahot pipe?

Any fault lights on ?


If you can get to a Walmart or hardware store, you can buy a portable electric heater and run this on generator or shore power until you get this figured out.

[Outbound]

Ditto on heat pumps not working in mid to low 30's temperatures, most homes have electric back up heat when heat pump is primary heat source to heat home.

[DFord]

I've been a HVAC/R tech since my time in the Air Force in 1966.

Residential heatpumps and RV heatpumps are much different. Their performance and operating characteristics cannot be compared.

Most RV heat pumps have only one fan motor with a double shaft - one end for the indoor fan and one end for the outdoor fan. They're not capable of a defrost cycle that would melt the frost that builds up on the outdoor coil and blocks the flow of air through it like a residential heatpump can. Even if they could, with the units on the roof, the melted frost would freeze up when temps are below freezing resulting in blocked drains or a huge icicle down the side of the RV. This is the main reason RV heatpumps won't work below 35-40 degrees F.

There's plenty of heat available in the air at and below the point of freezing but it gets harder to transfer it indoors. Residential heatpumps still produce more heat than straight resistance heaters well below -10F but because houses loose heat faster as it gets colder, they can't keep up and a supplemental source of heat is required to maintain the setting on the thermostat.

In short, even if you have heatpumps on an RV, you will need another source of heat to keep it warm when the temperature falls below freezing outdoors.

[Bill767]

If the AquaHot was completely cold it does take a few minutes to warm up all the liquid and then provide heat. If the diesel burner is working you should have heat in 10-15 minutes or so.

[pasdad1]

Originally Posted by Moira

Wow, i didnt know that about a heat pump, the fan shutting off and all. Thank you Buckshot. I know they are no good below 40 but thats what i have in the house, so i thought i would be able to heat this thing up slowly anyway.

Circulating the air thru the rooftop units when outside air is that cold, usually results in a colder motorhome I have found.

Electric resistance heaters can be used safely….if you want the safest one, get the oil-filled radiator type.

[153stars]

You probably need to change thermostat to furnace if you haven't to get heat from AH

[96 Wideglide]

Originally Posted by 00 Buckshot

Don't know what temperature you are trying to operate in but even if it is over 40 degrees a heat pump goes into a defrost cycle every so often depending on the outside temp. The fan shuts off and the compressor keeps on running. It reverses to generate heat outside to melt any ice building up on the coils. After this cycle it will reverse back and start blowing warm air again.

It sounds funny and will last a couple of minutes but this is normal with a HP.


My heat pumps work down to about 35 degrees but even when it is working perfectly it is blowing air less than your body temp so it feels cool .


Hope this makes sense.

This ^^^

Assuming you have the same Dometic Duo-therm heatpumps I have (as that's what Monaco installed), when the fan shuts down, just leave it.

If you look at your thermostat, it will display 'Defrost' on the bottom left corner. Within a couple of minutes, it will fire back up on it's own .

[ArtJoyce]

It sounds like it was working correctly. Warming up the house. Heatpumps will start to frost up on the outside coils depending on humidity. So after a certin amount of run time they go into a defrost cycle which is to turn on the AC on. The outside blow out warm air and inside cold air. Now if you power off the heat pump by turning off the circuit breaker they lose the defrost count and the first thing they will do is a defrost cycle. They need a starting point for the defrost count and they don't know if the coils are frosted or not.