AH Heaters

[al perna]

The AH controls the fans at the registers and turns them on when it gets a signal from the thermostat for a particular zone. If all else fails take the cover off the AH and make sure the ice-cube relays are well seated, sometimes they work themselves loose. The ice-cube relays receive a signal from the tstat and enable the zone circulating pump and fans accordingly.

Would the above quote mean, that if your heater only runs on low speed that the Ice cube relay is bad ? In preparing for winter I ran the AH this morning for a test and to take out the chill . I was reminded of a issue last winter where I could not get the fan to run at high speed at all .
I tried changing the thermostat
Raising the temp

any thoughts ?

[davidbrady]

Al,

I'm not aware of multispeed fans. My AH registers only functioned at a single speed.

[al perna]

so it is just 1 low speed ? this did not even warm the room last year . True the temps were 0 at night and 8 in the morning but I even had the room in and electric heat on . I thought maybe the fan was not working correctly ? I do know the kitchen and bath along with the bed room all seem to put out heat at a greater speed .

[al perna]

hi all , found this on the newell site , do you think this set up mirrors ours ?

in my coach there are 3 different fans supplying air from the aquahot heaters.

1. is the plenum in the bay that is discussed in a different thread in this section.

2. there are whisperfans that are self contained under the kitchen counter, in the bedroom and rear bath. they are wide and narrow. they have two computer like fans mounted to the back to blow air across the coils into the rooms.

3. then there is a similar unit that on mine is in the half bath and in boxes at the driver and passenger ankles. this uses a more squarish unit that has a larger single computer style fan on it.

the unit under the kitchen counter on mine had one of the two fans burned out. you can buy them from aquahot or parts suppliers.

but as usual, i wanted to source them myself.

you have to look at 4 things on these fans.
a. CFM rating....how much air they move
b. noise in db. how loud are they
c. current draw
d. temperature rating

the fan that was on the unit originally was a Silentfan SKUD12B4

it was 46CFM, 31db, 2600rpm, 2.9watts and rated at -20 to 70 degrees C. or about -4 to 158 F. the aquahot on mine gets to around 150 degrees at the register for the air coming out.

there are two types of computer fans. one has ball bearings and one has sleeve for a bearing. the sleeve bearing fans are only rated from -20 to 60C or -4 to 140F. so i opted for one like the original that was ball bearing.

Silentfan is no longer available unless you want to buy in quantities of 500-1000 and i didnt figure i could get that many of you to do a group buy. i think i got up to 3 or something like that.

so i compared fans. these are used in a variety of equipments so shopping is plentiful.

for the dual fan smaller whisper heater i ended up with a fan that was sold by http://www.mynewfan.com/servlet/StoreFront it is a 92mm across and 25mm thick. same as the one i took out

the guy who owns it is very helpful and friendly.

i bought the AD0912HB-A73GL http://www.mynewfan.com/servlet/the-619/...ase/Detail

for ten bucks

i bought enough to replace both fans on the unit.

it is 2400rpm, .08amps or about 1 watt, 44CFM, 31db.

as you can see from his site, you can get higher CFM fans, but they are noiser. i wanted it to have the lowest noise with acceptable air flow. so i went with one that was very close to the original.

they are screwed on from the back of the heater unit and didnt take too long to change out. very quiet and nice airflow.

next is the change the noisy fan that is on the unit in the mid bath.

i bought two different fans with different CFM to see how they sounded. it is a 120mm wide and 25mm thick unit. i bought two different ones to try. a 72cfm and 99cfm. of course the more cfm, the louder it is.

it is much more difficult to change since i have to actually take the unit out of the coach since the fan is riveted on and there is no room for power tools in the little area the unit is in.

the bearing are going out on that fan so it works fine but is very noisy.

the others are all ok.

thought you might be interested.

[GregOConnor]

there is three heat sources in my bus. the Aqua hot, Toe heaters and the electric heaters in the three air conditioners. the heaters in the Air conditioners are like toe heaters that use the air conditioner fan to push air past a heat element in each of the three rooftop ac units. that fan has several speeds. problem with the ac heaters is that they heat the hot air or the air that is sucked into the heater is the air at the headliner and when air is pushed out by the fan it doesnt drop like cold air does so the convection is bad.

[davidbrady]

Al,

I think your LXi uses pretty much the same fans as described in the Newell post. There are the registers in the basement, then there are the registers at the kick boards, then there's the variable speed bathroom fan. They're all probably as described in your post since they all probably came from AH.