[doug1111]

Pageyjim - poe oil unfortunately a lot of it goes to waste the smallest I can buy is a quart and only use an ounce and a little scared about the can sit around collecting moisture so don't use it. makes it a little expensive for the customer but I explained all this the older r22 using mineral oil cheap

 

[IRBH]

My rule of thumb- nothing to do with AC...

The younger the mother, the lamer the baby's name.

 

[11crv]

The best rule of thumb I ever saw is the print out of three homes. Small medium and large 2, 2.5, 3 tons. Then cut out the homes and stand 20' back the home that fits the cut is the proper Ac size. I saw this at a supy house many years ago it was funny

 

[jtrammel]

Rule of thumb duct sizing courtesy of Wayne (penderway)
http://efficientcomfort.net/Charts/Rules_and_Rules_of_Thumb_for_Duct_Systems.pdf

 

[Core_d]

Things like 20 Degree Delta T on an Evaporator coil is OK as long as we realize that is just the "sweet spot" and the range can be 15-25.............out the condenser the air should be roughly 35 degrees warmer than ambient to cover your delta T of 20 ( from the indoor) and Heat Of Compression approx. 15 degrees...........Liquid line should always be warmer than ambiant

Could be as low as 13 if very humid

 

[BBeerme]

Or, if you're a freakin' red neck like Tonya Harding was [no offense intended to other red necks], then the actual phrase is:

"You can look at it half cup full, half cup empty"

http://www.tampabay.com/sports/olympics/nbc-to-look-back-at-nancy-kerrigan-and-tonya-harding/2166759

different rules of thumb guesstimations four different climates.customers are always asking if it is low on refrigerant how much do you think it would take to fill it up?rule of thumb approximately 30 percent of its full charge?the residential system just started to freeze a little frost on the copper line outside. any comments on the 30 percent? agree disagree? what is your guesstimate rule of thumb ballpark?half full or half empty?

 

[BBeerme]

Here's a good rule of thumb:

If it's not working out, get a bigger hammer. And if it breaks, it was already broken.

https://www.youtube.com/watch?v=baR7aMe7rgk

 

[BALloyd]

#1 Rule of thumb.................Never use Rules Of Thumb:cheers:

we provide verifiable in court documents- ballparks are not allowed

But...........Great Thread................OK Paydays on Friday and S@@t don't flow uphill--my 2 rules

Also. Do not chew your nails.

 

[viceman]

The best rule of thumb I ever saw is the print out of three homes. Small medium and large 2, 2.5, 3 tons. Then cut out the homes and stand 20' back the home that fits the cut is the proper Ac size. I saw this at a supy house many years ago it was funny

Funny you mention this. I used to have that. i was just looking for it last week but can't find it.

 

[BBeerme]

Here ya go.

Funny you mention this. I used to have that. i was just looking for it last week but can't find it.

 

[mrkelly]

Back in the old day's,We used a similar method using your hand & fingers for tonnage with your thumb for 1/2 ton when 1 finger was too much.
Much more accurate.:grin2:

 

[pageyjim]

I use rule of thumb guidelines on every call and everyone gets a tail light guarantee.

 

[doug1111]

Pageyjim - taillight guarantee? please explain.small job condenser fan motor capacitor replace I check rule of thumb & ball park after replace the capacitor TD on condenser TD on inside thermostat if it cycles itself off ask customer if system was okay before fan motor was out and ask if they feel I need to do other checks. the rule of thumb in ball park procedures may lead to requesting check other things?

 

[pageyjim]

Pageyjim - taillight guarantee? please explain.small job condenser fan motor capacitor replace I check rule of thumb & ball park after replace the capacitor TD on condenser TD on inside thermostat if it cycles itself off ask customer if system was okay before fan motor was out and ask if they feel I need to do other checks. the rule of thumb in ball park procedures may lead to requesting check other things?

A tail light guarantee is good for as long you can see my tail lights when I'm driving away.

Time consuming but always good to go over everything after a repair I guess.

 

[doug1111]

Pageyjim LOL cool I like that taillight guarantee better than nothing.and sounds better than no guarantee. has anyone ever called you before your tail lights got out of sight? LOL - rule of thumb guesstimation on heat load calculation comes in handy when you're trying to explain BS the customer that's their system is wore out aged and undersized for the amount of square footage they are trying to cool - Central Florida I've been using 450 square feet per ton of AC? to get a certified heat load calculation is costly and very few are certified in doing heat load calculations.

 

[BBeerme]

In all seriousness, there are a ton of those 'rules of thumbs' that I use on a daily basis. It's just that as soon as you begin discussing them, there will always be those naysayers who come out of the woodwork and cite an example where the numbers don't crunch.

Take TD for example. That is a fantastic rule of thumb for both sides of the system. And can quickly give you a glimpse into how well or how bad a system may be working. That thread brought out several who tried to bash it. Ultimately, most of the bashers couldn't defend their stance and came around to see how simple it is to apply.

You just have to know what you are working on and how different applications will create different TD's.

 

[rider77]

The last time I used a ballpark guesstimation my wife wound up pregnant

 

[BBeerme]

That's because you were thinking with your little head and not your big head.

Did you name that kid 'Ooopsie'?

The last time I used a ballpark guesstimation my wife wound up pregnant

 

[rider77]

That's because you were thinking with your little head and not your big head.

Did you name that kid 'Ooopsie'?

Wit Drew Soonersteen

 

[BBeerme]

LOL

Wit Drew Soonersteen